AGENUS INC - Annual Report: 2015 (Form 10-K)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-K

For the fiscal year ended December 31, 2015

or

For the transition period from             to

Commission File Number: 000-29089

Agenus Inc.

(exact name of registrant as specified in its charter)

3 Forbes Road, Lexington, Massachusetts 02421

(Address of principal executive offices, including zip code)

Registrant’s telephone number, including area code:

(781) 674-4400

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  o    No  þ

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  o    No  þ

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  þ    No  o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulations S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).  þ

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. þ

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  o    No  þ

The aggregate market value of voting stock held by non-affiliates of the registrant as of June 30, 2015 was: $571.0 million. There were 86,516,484 shares of the registrant’s Common Stock outstanding as of February 29, 2016.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the definitive proxy statement for the registrant’s 2016 Annual Meeting of Stockholders, which definitive proxy statement will be filed with the Securities and Exchange Commission not later than 120 days after the registrant’s fiscal year end of December 31, 2015, are incorporated by reference into Part III of this Annual Report on Form 10-K.

TABLE OF CONTENTS

Note Regarding Forward-Looking Statements

This Annual Report on Form 10-K and other written and oral statements the Company makes from time to time contain forward-looking statements. You can identify these forward-looking statements by the fact they use words such as “could,” “expect,” “anticipate,” “estimate,” “target,” “may,” “project,” “guidance,” “intend,” “plan,” “believe,” “will,” “potential,” “opportunity,” “future” and other words and terms of similar meaning. Forward-looking statements include discussion of future operating or financial performance. You also can identify forward-looking statements by the fact that they do not relate strictly to historical or current facts. Forward-looking statements involve risks and uncertainties that could delay, divert or change any of them, and could cause actual outcomes to differ materially. These statements relate to, among other things, our business strategy, our research and development, our product development efforts, our ability to commercialize our product candidates, the activities of our licensees, our prospects for initiating partnerships or collaborations, the timing of the introduction of products, the effect of new accounting pronouncements, our future operating results and our potential profitability, availability of additional capital as well as our plans, objectives, expectations, and intentions.

Although we believe we have been prudent in our plans and assumptions, no assurance can be given that any goal or plan set forth in forward-looking statements can be achieved, and readers are cautioned not to place undue reliance on such statements, which speak only as of the date of this report. We undertake no obligation to release publicly any revisions to forward-looking statements as a result of new information, future events or otherwise.

The risks identified in this Annual Report on Form 10-K, including, without limitation, the risks set forth in Part I-Item 1A. “Risk Factors,” could cause actual results to differ materially from forward-looking statements contained in this Annual Report on Form 10-K. We encourage you to read those descriptions carefully. Such statements should be evaluated in light of all the information contained in this document.

ASV ^TM, AutoSynVax ^TM, Oncophage^®, PSV ^TM, PhosphoSynVax ^TM, Prophage^TM, Retrocyte Display^TM, SECANT^® and Stimulon^® are trademarks of Agenus Inc. and its subsidiaries. All rights reserved.

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PART I

Our Business

We are an immuno-oncology company focused on the discovery and development of revolutionary new treatments that engage the body’s immune system to benefit patients suffering from cancer. We have focused on immuno-oncology since our inception over 20 years ago, and today we have a series of platforms and capabilities across an array of immunological modalities. At Agenus, we have embraced the concept that cancers are complicated diseases requiring multi-pronged approaches to treatment. We believe that the future of cancer therapy will depend upon the ability to identify and possess the best treatment regime for an individual based on the specific cancer and patient profile. We are building the capabilities and platforms to address these complex needs.

We are developing a comprehensive immuno-oncology portfolio driven by the following platforms and programs, which we intend to utilize individually and in combination:

Our programs aim to stimulate the immune system to recognize and eradicate cancer cells and to disable the mechanisms that cancer cells employ to evade detection and destruction by the immune system. By combining multiple powerful antibody platforms, we have established a highly integrated approach to target identification and validation, and for the discovery, development and manufacture of monoclonal antibodies that modulate targets of interest. The breadth of our portfolio gives us the ability to combine our proprietary antibodies, vaccines, and adjuvants to explore and optimize cancer treatments. Our strategy is to develop these agents either alone or in combinations to yield best-in-class treatments.

We assess development, commercialization and partnering strategies for each of our product candidates periodically based on several factors, including pre-clinical and clinical trial results, competitive positioning and funding requirements and resources. We are currently collaborating with companies such as Incyte Corporation, Merck Sharpe & Dohme and Recepta Biopharma SA. Through these alliances, as well as our own internal programs, we currently have over a dozen antibody programs, including our anti-CTLA-4 (partnered with Recepta for certain South America territories) and anti-GITR (partnered with Incyte) antibody programs that each received U.S. Federal Drug Administration, or FDA, clearance to commence clinical trials in January 2016. We expect to initiate these trials in the first half of 2016.

We are also advancing a series of Heat Shock Protein, or HSP, peptide-based vaccines to treat cancer. In July 2014, we reported positive results from a Phase 2 clinical trial with our Prophage vaccine, which showed that patients with newly-diagnosed glioblastoma, or ndGBM, who were treated with a combination of our Prophage vaccine and standard of care showed substantial improvement both in progression-free survival and median overall survival, each as compared to historical control data. We plan to advance our Prophage vaccine into a randomized, well-controlled clinical trial for ndGBM in the second half of 2016. We also reported positive results in June 2014 from a Phase 2 clinical trial with our synthetic HerpV vaccine candidate for genital herpes. Although we determined not to advance this product candidate in herpes, based on our findings we launched our AutoSynVax, or ASV, synthetic cancer vaccine program in 2015, and we plan to initiate our first clinical trial for this program in the second half of 2016.

Our QS-21 Stimulon adjuvant is partnered with GlaxoSmithKline plc., or GSK, and is a key component in multiple GSK vaccine programs that target prophylactic or therapeutic impact in a variety of infectious diseases and cancer. These programs are in various stages, with the most advanced being GSK’s shingles and malaria programs, for which GSK announced positive Phase 3 results in December 2014 and October 2013, respectively. In September 2015, we monetized a portion of the future royalties we are contractually entitled to receive from GSK from sales of its shingles and malaria vaccines and received net proceeds of approximately $78.2 million.

Our business activities include product research and development, intellectual property prosecution, manufacturing, regulatory and clinical affairs, corporate finance and development activities, and support of our collaborations. Our product candidates require clinical trials and approvals from regulatory agencies, as well as acceptance in the marketplace. Part of our strategy is to develop and commercialize some of our product candidates by continuing our existing arrangements with academic and corporate collaborators and licensees and by entering into new collaborations.

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Our common stock is currently listed on The Nasdaq Capital Market under the symbol “AGEN.”

Our Antibody Discovery Platforms and CPM Programs

In February 2014, we acquired our Retroviral B Lymphocyte Display, or Retrocyte Display, platform as a result of our acquisition of 4-Antibody AG, or 4-AB, a private European-based biopharmaceutical company. Retrocyte Display is a proprietary antibody discovery platform designed for the rapid discovery and optimization of fully-human and humanized monoclonal antibodies against a wide array of molecular targets. Our Retrocyte Display platform uses a high-throughput approach incorporating human antibody libraries expressed in mammalian B-lymphocytes and is designed to screen and generate therapeutic antibody drug candidates. We complemented this platform in April 2015 with the acquisition of our SECANT yeast display antibody discovery platform from Celexion, LLC, or Celexion, and in September 2015 with the exclusive license to a phage display library.  The addition of the phage display library and SECANT yeast display platform in combination with our Retrocyte Display platform gives us broad, integrated and highly productive antibody discovery platforms. Each of these complementary platforms is designed to yield diverse antibody candidates, and together they increase the variety of addressable targets and diversity of antibody candidates. These approaches are intended to combine the speed, diversity, and selectivity of our discovery platforms to yield high affinity antibodies and bolster our antibody discovery capabilities internally and for our partners. We now have the potential to integrate three high quality complementary antibody display technologies with innovative computational, structured-based design approaches to discover and optimize best-in-class monoclonal antibodies as future medicines.

In addition to the use of our antibody discovery platforms that are designed to drive the discovery of future CPM antibody candidates, we may also employ a variety of techniques to identify and optimize our antibody candidates. We will use our recently acquired capabilities to accelerate the development of our portfolio of CPM candidates for our own programs and those of our partners and potential collaborators. These added capabilities will position us to exploit new technological and development capabilities and also to facilitate new partnership opportunities beyond our current portfolio.  

There are dozens of checkpoints as well as ligands that interact with these checkpoints, each of which are expressed on various cell types involved in immune responses. In most instances, these checkpoints and ligands work to control and shape our immune responses and promote our health. In the last decade, the biotechnology industry has begun to understand that these checkpoint processes can also intensify diseases, including cancer and auto-immune diseases. Understanding the roles that checkpoint processes can play in cancer has led to advances in the treatment of many patients with advanced cancer. We have learned that, while cancer can be recognized by the immune system as “non-self” and trigger potential immune control, cancer can hijack checkpoint processes to protect itself from either immune detection or immune destruction. Advances in cancer treatment are emerging based on therapeutic monoclonal antibodies targeting checkpoint receptors or their ligands, facilitating immune response against cancers. Some of the CPM antibodies that have been developed to date include Bristol-Myers Squibb’s Yervoy^® (CTLA-4 antagonist) and Opdivo^® (PD-1 antagonist) and Merck’s Keytruda^® (PD-1 antagonist). Agents like these have not only led to increased protracted survival for many patients with certain forms of cancer, such as melanoma and lung cancer, but they are also leading to apparent cures in some patients with advanced metastatic cancer.

Our strategy includes identifying opportunities to advance our portfolio of CPMs as single agents and in optimized combinations, including potential combinations with our vaccines and other agents. We and our partners currently have pre-clinical and clinical programs exploring fully human and humanized monoclonal antibodies against several important checkpoint targets including GITR, OX40, CTLA-4, PD-1, TIM-3, LAG-3, CEACAM1 and other undisclosed targets. We are working to discover and develop monoclonal CPM antibodies to modulate the activity of these targets, selectively reactivate the immune system and thwart attempts by cancer to evade destruction. We believe these CPM antibodies will be beneficial in the treatment of cancer patients by allowing the immune system to more effectively recognize and destroy cancer cells.

In 2015, we filed investigational new drug applications (INDs) for antibodies targeting CTLA-4 and GITR (filed with Incyte), and in January 2016 we announced that the FDA gave clearance to begin clinical trials with these two CPM candidates. Clinical trials with these CPMs are planned to initiate in the first half of 2016. In addition, we have product candidates targeting OX40 and PD-1 advancing into IND-enabling studies, and we expect to initiate clinical trials for one or more of these compounds during the second half of 2016.

Partnered CPM Programs

In January 2015, we entered into a broad, global alliance with Incyte to discover, develop and commercialize novel immuno-therapeutics using our antibody platforms. The collaboration was initially focused on four CPM programs targeting GITR, OX40, TIM-3 and LAG-3, and in November 2015 we expanded our alliance by adding three additional novel undisclosed CPM targets. Pursuant to the terms of the collaboration, Incyte made non-creditable, non-refundable upfront payments to us totaling $25.0 million. Targets under the collaboration are designated as either profit-share programs, where the parties share all costs and profits equally, or royalty-bearing programs, where Incyte funds all costs, and we are eligible to receive milestones and royalties. The programs targeting

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GITR, OX40 and two of the undisclosed targets are profit-share programs, while the other targets currently under collaboration are royalty-bearing programs. For each profit-share product, we are eligible to receive up to $20.0 million in future contingent development milestones. For each royalty-bearing product, we are eligible to receive (i) up to $155.0 million in future contingent development, regulatory, and commercialization milestones and (ii) tiered royalties on global net sales at rates generally ranging from 6%-12%. For each royalty-bearing product, we also have the right to elect to co-fund 30% of the development costs incurred following initiation of pivotal clinical trials in return for increased royalties. In addition, we and Incyte have the option to jointly nominate and pursue the development and commercialization of CPM programs that target additional checkpoint targets during a five-year discovery period. For each antibody arising from a program that the parties elect to bring into our collaboration, we will have the option to designate that program as a profit-share or royalty-bearing program. Concurrent with the execution of the collaboration agreement, we and Incyte also entered into a stock purchase agreement pursuant to which Incyte purchased approximately 7.76 million shares of our common stock for an aggregate purchase price of $35.0 million, or approximately $4.51 per share.

In addition, in April 2014, we entered into a collaboration and license agreement with Merck to discover and optimize fully-human antibodies against two undisclosed CPM targets. Under the terms of the agreement, Merck is responsible for the clinical development and commercialization of antibodies generated under the collaboration, and we are eligible to receive approximately $100.0 million in potential payments associated with the completion of certain clinical, regulatory and commercial milestones, as well as royalty payments on any worldwide product sales. We also continue to collaborate with Recepta SA on the development of antibodies targeting CTLA-4 and PD-1, and we expect to continue exploring additional future collaborations.

Vaccine Platform Programs

Our current vaccine platform programs for the treatment of cancer include our HSP based Prophage vaccine candidates, and our synthetic vaccine candidates, ASV and PhosphoSynVax^™, or PSV^™.

HSPs are a group of proteins present at high levels in most mammalian cells. Their expression is increased when cells are exposed to elevated temperatures or other stresses. A potential role for HSPs in regulating immune responses was revealed when it was first discovered that HSP complexes purified from cancer cells produced immunity to cancer, whereas HSP complexes purified from normal tissue did not. This discovery led to the understanding that HSPs bind to and carry a broad sampling of the protein environment within cells, including mutant proteins that might arise from genetic mutations within cancer cells. It was further shown that immunization with HSP complexes purified from tumors and used as vaccines to interact with antigen-presenting cells that then cross present the HSP-associated antigenic peptides to generate a CD4 and CD8 positive T-cell immune response.  These activated T-cells target the cancer cells of the tumor from which the HSP complexes were derived. In order to provide effective immunization in this manner, HSP complexes isolated from cancer cells are particularly effective. Since HSPs are expressed in all tumor cells, the approach of immunizing with the HSP complexes isolated from a particular tumor is broadly applicable to a variety of cancer types. We believe that we pioneered the use of gp96, an HSP, purified from a patient’s own tumor tissue, as a way to make vaccines tailored to stimulating immune recognition and potential immune control of a specific patient’s cancer.

Because cancer is a highly variable disease from one patient to another, due to extensive mutation of cancer cells, we believe that a patient-specific vaccination approach is optimal to generate a more robust and targeted immune response against the disease.

Prophage Vaccine Candidates

Our Prophage cancer vaccine candidates are autologous therapies derived from patient cancer tissues that are surgically removed. As a result, a Prophage vaccine tailored for a patient is produced from a broad sampling of potentially antigenic mutant proteins from such patient’s tumor. Prophage vaccines are designed to program the body’s immune system to target only the specific cells expressing these mutant antigens, thereby reducing the risk that the body’s immune response against the tumor after vaccination will also affect healthy tissue and cause debilitating side effects often associated with chemotherapy and radiation therapy.

To date, more than 1,000 patients have been treated with Prophage vaccines in clinical trials, covering a broad range of cancer types, and no serious immune-mediated side effects have been observed. The results of these trials have been published and/or presented at scientific conferences. These results indicate observable clinical and/or immunological activity across many types of cancer. Taken together, these trials show promising evidence of clinical benefit from Prophage vaccines and also establish that such vaccines can be effectively manufactured under current good manufacturing practices (“cGMP”), conditions and internationally distributed.

Our Prophage vaccines are currently being studied in two different settings of GBM: patients who have been newly diagnosed as well as those with recurrent disease. Glioblastoma is the most common primary malignant brain tumor and accounts for the majority of diagnoses of malignant cancers of the brain.

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GBM is a cancer affecting the central nervous system arising from glial cells that become malignant, and it is currently a rapidly fatal disease. The American Cancer Society estimates that 23,770 new cases of brain and other nervous system cancer will be diagnosed in the United States during 2016, and that 16,050 people in the United States will die from these tumors during 2016.

In December 2013, we published our Phase 2 results demonstrating that more than 90% of the patients treated with Prophage vaccine were alive at six months after surgery and 30% were alive at 12 months after surgery. Additionally, the median overall survival was approximately 11 months. This compares favorably to historical control data with expected median survival for recurrent GBM patients of three to nine months. The data were published in a manuscript in Neuro-Oncology, the official journal of the Society of Neuro-Oncology.

In July 2014, we announced final results from a single-arm, multiple-center, open-label Phase 2 clinical trial in 46 patients with ndGBM treated with our Prophage vaccine in combination with standard of care: surgical resection, radiation and temozolomide. These results showed that patients treated with Prophage vaccine had a median progression free survival, or PFS, of 18 months, with 33% of patients progression free at 24 months. These results indicate improvement compared to historical data for patients treated with the standard of care, for which median PFS is six to nine months. Median overall survival, or OS, the primary endpoint of the trial, was 23.8 months and remains durable in patients treated with Prophage. In this study, the 12 month survival rate was 85% with many surviving beyond the 24 month study period. For the standard of care alone, studies have shown the historical median OS is approximately 16-19 months. Potential benefit from Prophage appears to be more evident in patients with less elevated expression of the checkpoint ligand PD-L1 on their white blood cells. This defines a potential group of responders to Prophage plus standard of care and also suggests a potential benefit from the combination of Prophage with CPMs like PD-1 antagonists in patients with more elevated PD-L1 on peripheral mononuclear white blood cells.  In data reported at the American Society of Clinical Oncology, or ASCO, in 2015, a pre-defined subgroup of patients with less elevated monocyte PD-L1 expression (below the median of 54.5%) showed  substantially longer PFS (~27.2 months vs historical median PFS of six to nine months) and OS (~47 months vs a historical median of 16-18.8 months). Durability of a response was evident in this cohort with approximately one third of the patients with less elevated PD-L1 living four years or longer.

In addition to the Phase 2 trial in patients with ndGBM, the Alliance for Clinical Trials in Oncology, a cooperative group of the National Cancer Institute, or NCI, is supporting a randomized Phase 2 clinical trial of the Prophage vaccine in combination with bevacizumab in 222 patients with surgically resectable, recurrent GBM. This trial is the largest vaccine trial ever funded by the NCI in brain tumors and the largest vaccine study ever conducted in combination with bevacizumab. The study is designed to compare the efficacy of the Prophage vaccine administered with bevacizumab either concomitantly or at progression to treatment with bevacizumab alone. The primary endpoint of this study is overall survival. This study design is supported in part by previous research indicating a potential synergistic effect between the mechanisms of action behind both the Prophage vaccine and bevacizumab. While the NCI Alliance has confirmed a commitment to completion of the trial, to date, it has been slow to recruit patients.

ASV Vaccine Program

In June 2014 we reported positive results from a Phase 2 clinical trial with our synthetic HerpV vaccine candidate for genital herpes. This candidate was the first potential recombinant, off-the-shelf application of our HSP technology. The study demonstrated that the HSP70-peptide-QS21 vaccine produced significant CD4 and CD8 positive T-cell responses to antigenic peptides, and that the side effects were mild to moderate and tolerable. We decided not to advance with this technology in herpes but based on our findings we launched our ASV synthetic cancer vaccine program in 2015. We plan to initiate clinical trials for this program in the second half of 2016.

The objective of our ASV program is to develop a fully synthetic, yet individual patient specific tumor vaccine targeting the neo-epitope landscape of each patient’s cancer. With a small amount of a patient’s tumor as a sample, our ASV program is designed to utilize highly complex bioinformatics and next generation sequencing technologies to identify mutations in a tumor’s DNA and RNA. Once these mutations have been identified, we will manufacture synthetic peptides, load these peptides on to our recombinant HSP70 and deliver a fully synthetic polyvalent vaccine to the patient. We believe that the HSP70 platform will shuttle the mutated peptides to sites where they are recognized by the immune system and elicit a cytotoxic and helper T cell response in patients with cancer. We expect that once identified, these tumor cells will be killed and cleared by the immune system.

Sequencing a tumor’s genome has become increasingly common and more cost effective compared to sequencing techniques utilized only a decade ago. ASV represents an unprecedented opportunity to integrate advances in information technology, including next generation sequencing and bioinformatics, with advances in biotechnology to develop individualized cancer vaccines. Tumors harbor a unique set of genetic mutations, some of which can result in mutant proteins. Tumor cells naturally degrade these mutant proteins to produce mutant peptides, and because over 98% of mutations are unique to individual tumors, advances in high-performance computing infrastructure make it feasible to target and synthesize these mutations.

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Identifying and manufacturing selected synthetic immunogenic mutant peptides is anticipated to recapitulate the potential benefits of Prophage as an autologous cancer vaccine in patients where tumor material is insufficient for standard Prophage processing. Assembling synthetically predicted antigens with a recombinant HSP vaccine should allow us to create quantities of autologous vaccines producing lasting benefits for patients with cancer. We plan to initiate the first clinical trial with our ASV vaccine in the second half of 2016.

PSV Vaccine Candidate

PSV is a vaccine candidate designed to induce immunity against a novel class of tumor specific neo-epitopes: those arising from dysregulated phosphorylation of various proteins in malignant cells, rather than from mutations producing abnormal protein sequences. In cancer cells, protein sequences that can become phosphorylated (a phosphate group is added to particular amino acid residues) that are not normally phosphorylated, as a consequence of dysregulated biochemical processes. Some of these mis-phosphorylated peptides can be processed by the cellular machinery that leads to antigen presentation of the surface of cells, and there they can potentially be recognized by specific cytotoxic T cells. PhosImmune has described many hundreds of such phosphoprotein neo-epitopes characterizing different forms of cancer, such as lung cancer, specific leukemias, ovarian cancer, colon cancer and others. When this happens, it can lead to the destruction of the cancer cells. PSV is a group of potential product candidates intended to induce cellular immunity to abnormal phosphopeptide neo-epitopes characterizing various forms of cancer. Phosphopeptides (or phosphopeptide analogues) can be synthesized and complexed with HSP70, in a manner analogous to that used in the generation of Agenus’ previous HerpV vaccine candidate. HerpV has successfully completed a placebo-controlled Phase 2 study, which demonstrated good cellular and humoral responses to synthetic peptide immunogens complexed with HSP70. We believe that similar responses can be obtained to phosphopeptide or phosphopeptide analogues bound to HSP70 used as vaccines. Mutation-based neo-epitopes, which will form the basis for the immunogens used in ASV, are almost always particular to a given patient. Therefore, ASV will need to be a largely individualized vaccine product. In contrast to this, some phosphorylation-based neo-epitopes are apparently found on specific types of cancer in many patients, suggesting that the immunogens used in PSV, while tailored to a particular patient, will be useful in other patients with related forms of cancer. Studies to optimize the immunogens to be used in PSV are on-going. PSV could prove to be particularly useful in enabling activation of immunity against cancer that contains fewer mutation-based neo-epitopes. Currently, scientists believe that it will be difficult to extend immune-based treatments to address these less mutant tumors. As with ASV, the HSP70 platform shuttles the phosphopeptide tumor targets, or PTTs to sites where they are recognized by the immune system and safely elicit an immune response in patients killing and clearing the tumor cells.

We acquired the phosphopeptide-based neo-epitope technology from PhosImmune in December 2015. Under the terms of the agreement, we paid PhosImmune’s equity holders an upfront payment of $2.5 million in cash and $7.4 million in common stock at closing. In addition, payments of up to $35.0 million in cash and/or common stock at our election are payable upon the achievement of certain milestones.

The acquisition of PhosImmune allows us to benefit from the peptide analytics expertise of PhosImmune’s founders to create both patient-specific and off-the-shelf cancer vaccines products while leveraging our ASV vaccine developments.

QS-21 Stimulon Adjuvant

QS-21 Stimulon is an adjuvant, a substance added to a vaccine or other immunotherapy that is intended to enhance immune response to the target antigens. A natural product, QS-21 Stimulon is a triterpene glycoside, or saponin, purified from the bark of the Chilean soapbark tree, Quillaja saponaria. QS-21 Stimulon has the ability to stimulate antibody immune response and has also been shown to activate cellular immunity. QS-21 Stimulon has become a key component in the development of investigational preventive vaccine formulations across a wide variety of diseases. These studies have been carried out by academic institutions and pharmaceutical companies in the United States and internationally. A number of these studies have shown QS-21 Stimulon to be significantly more effective in stimulating immune responses than aluminum hydroxide or aluminum phosphate, the adjuvants most commonly used in approved vaccines in the United States today.

Partnered QS-21 Stimulon Programs

In July 2006, we entered into a license agreement and a supply agreement with GSK for the use of QS-21 Stimulon (the “GSK License Agreement” and the “GSK Supply Agreement,” respectively). In January 2009, we entered into an Amended and Restated Manufacturing Technology Transfer and Supply Agreement (the “Amended GSK Supply Agreement”) under which GSK has the right to manufacture all of its requirements of commercial grade QS-21 Stimulon. GSK is obligated to supply us, or our affiliates, licensees, or customers, certain quantities of commercial grade QS-21 Stimulon for a stated period of time. In March 2012, we entered into a First Right to Negotiate and Amendment Agreement amending the GSK License Agreement and the Amended GSK Supply Agreement to clarify and include additional rights for the use of QS-21 Stimulon (the “GSK First Right to Negotiate Agreement”). In addition, we granted GSK the first right to negotiate for the purchase of the Company or certain of our assets, which right expires in March 2017. As consideration for entering into the GSK First Right to Negotiate Agreement, GSK paid us an upfront, non-refundable

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payment of $9.0 million, $2.5 million of which is creditable toward future royalty payments. We refer to the GSK License Agreement, the Amended GSK Supply Agreement and the GSK First Right to Negotiate Agreement collectively as the GSK Agreements. As of December 31, 2015, we had received $23.3 million of a potential $24.3 million in upfront and milestone payments under the GSK Agreements. Under the terms of the Agreement, we are generally entitled to receive 2% royalties on net sales of prophylactic vaccines for a period of 10 years after the first commercial sale of a resulting GSK product, with some exceptions. The GSK License and Amended GSK Supply Agreements may be terminated by either party upon a material breach if the breach is not cured within the time specified in the respective agreement. The termination or expiration of the GSK License Agreement does not relieve either party from any obligation which accrued prior to the termination or expiration. Among other provisions, the milestone payment obligations survive termination or expiration of the GSK Agreements for any reason, and the license rights granted to GSK survive expiration of the GSK License Agreement. The license rights and payment obligations of GSK under the Amended GSK Supply Agreement survive termination or expiration, except that GSK's license rights and future royalty obligations do not survive if we terminate due to GSK's material breach unless we elect otherwise.

In September 2015, we monetized a portion of the royalties associated with the GSK License Agreement to an investor group led by Oberland Capital Management for up to $115.0 million in the form of a non-dilutive royalty transaction. Under the terms of a Note Purchase Agreement with the investor group (the “Note Purchase Agreement”) we received $100.0 million at closing for which the investors will have the right to receive 100% of our worldwide royalties under the GSK License Agreement on sales of GSK’s shingles (HZ/su) and malaria (RTS,S) prophylactic vaccine products that contain our QS-21 Stimulon adjuvant to pay down principle and interest. Once all principle and interest under the Note Purchase Agreement has been paid, any and all remaining royalties from the GSK License Agreement will accrue to us. The Note Purchase Agreement is designed to allow us to capture both the near and longer term benefit associated royalties from GSK’s vaccine products containing our QS-21 Stimulon. At our option, we are entitled to receive an additional $15.0 million in cash from the investors after approval of HZ/su by the FDA, provided such approval does not occur later than June 30, 2018. Also at our option, we have the right to buy back the loan at any time under pre-specified terms. The monetization of these royalty rights allows us to advance a significant portion of the future value of our royalty stream while still allowing us to retain any future monetary upside after the Note Purchase Agreement terms have been satisfied.

QS-21 Stimulon is a key component included in certain of GSK's proprietary adjuvant systems, and we believe that a number of GSK's vaccine candidates currently in development are formulated using adjuvant systems containing QS-21 Stimulon, including its shingles and malaria vaccine candidates which have successfully completed Phase 3 clinical trials. In December 2014, GSK reported that its ZOE-50 Phase 3 clinical trial evaluating the efficacy of its shingles vaccine candidate, HZ/su, met its primary endpoint. Analysis of the primary endpoint showed that HZ/su reduced the risk of shingles by 97.2% in adults aged 50 years and older compared to placebo. In addition, GSK has reported two positive Phase 3 clinical trials of its RTS,S malaria vaccine candidate containing QS-21 Stimulon, which was accepted by the EMA for regulatory review in July 2014. In November 2013, Phase 3 data were reported that demonstrated that RTS,S helps protect children and infants from clinical malaria up to 18 months post vaccination. In November 2012, The New England Journal of Medicine published results of a second Phase 3 trial for RTS,S. In this study, infants aged 6-12 weeks receiving the RTS,S vaccine candidate experienced one-third fewer episodes of both clinical and severe malaria and experienced similar reactions to the injection when compared to those who received the control meningococcal C conjugate vaccine. GSK met both of its co-primary endpoints in the large ongoing efficacy clinical trial. In October 2011, The New England Journal of Medicine published results of the first Phase 3 clinical trial of GSK’s RTS,S malaria vaccine candidate containing QS-21 Stimulon. Results of the study, the largest malaria vaccine efficacy and safety clinical trial ever conducted, demonstrate that RTS,S provided African children with significant protection against clinical and severe malaria, reducing risk by 56% and 47%, respectively, for the 12-month period following vaccination.

Assuming regulatory approval, the first products containing QS-21 Stimulon are anticipated to be launched by GSK in 2018.  We do not incur clinical development costs for products partnered with GSK. Our other licensee, Janssen Science Ireland UC, recently notified us that they were terminating their license for use of QS-21 Stimulon.    

Manufacturing

Antibody manufacturing

In December 2015, we acquired XOMA Corporation’s antibody manufacturing pilot plant in Berkeley, CA. A team of former XOMA employees with valuable chemistry, manufacturing and controls experience has joined us and will continue to operate the facility. The pilot plant, referred to as “Agenus West,” was acquired to enable us to manufacture antibodies for some of our own CPM programs and those of existing and potential third party collaborators. We expect the pilot plant to provide antibody production development expertise, antibody drug substance to support clinical proof-of-concept studies, and to facilitate our future GMP antibody production requirements. We also expect to utilize our Agenus West pilot plant capabilities to accelerate antibody delivery speed, improve quality and increase product yield while providing us with greater manufacturing flexibility all at reduced costs. We believe our Agenus West pilot plant manufacturing facility could accelerate the time to the clinic and into product commercialization.

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Prophage

Prophage vaccines are manufactured in our Lexington, MA facility. We estimate that this facility could support the production of up to 4,000 batches per year.

Each Prophage vaccine is manufactured using a patient’s own tumor. After the patient undergoes surgery to remove cancerous tumor tissue, the tumor is shipped frozen in a specially designed kit provided we provide to our Lexington, Massachusetts facility. Each Prophage vaccine is produced in approximately ten hours, after which it undergoes extensive quality testing for approximately two weeks. The turnaround time from the date of surgery to delivery of vaccine is approximately three to four weeks, which generally fits well with the patient’s recovery time from surgery. Once we release the vaccine, it is shipped frozen overnight to the hospital pharmacy or clinician. Prophage vaccines are given as a simple intradermal injection. Agenus has established, within a single facility, well-defined, cost efficient manufacturing under GMPs.

After manufacturing, Prophage vaccines are tested and released by our quality systems staff. The quality control organization performs a series of release assays designed to ensure that the product meets all applicable specifications. Our quality assurance staff also reviews manufacturing and quality control records prior to batch release in an effort to assure conformance with current GMP, or cGMP, as mandated by the FDA and foreign regulatory agencies.

Our manufacturing staff is rigorously trained and routinely evaluated for conformance to manufacturing procedures and quality standards. This oversight is intended to ensure compliance with FDA and foreign regulations and to provide consistent vaccine output. Our quality control and quality assurance staff is similarly trained and evaluated as part of our effort to ensure consistency in the testing and release of the product, as well as consistency in materials, equipment and facilities.

QS-21 Stimulon

Except in the case of GSK, we have retained worldwide manufacturing rights for QS-21 Stimulon, and we have the right to subcontract manufacturing for QS-21 Stimulon. In addition, under the terms of our agreement with GSK, upon request by us, GSK is committed to supply certain quantities of commercial grade QS-21 Stimulon to us and our licensees for a fixed period of time.

Intellectual Property Portfolio

We seek to protect our technologies through a combination of patents, trade secrets and know-how, and we currently own, co-own or have exclusive rights to approximately 50 issued United States patents and approximately 120 issued foreign patents. Our issued patents include those that cover uses of our core technologies in combination with other agents. Such core technologies include HSP-based vaccines for the treatment of cancers and treatment/prevention of infectious diseases, and saponin adjuvants.  We also own, co-own or have exclusive rights to approximately 50 pending United States patent applications and approximately 50 pending foreign patent applications. We may not have rights in all territories where we may pursue regulatory approval for Prophage vaccine candidates.

Through our acquisitions of 4-AB, PhosImmune and certain assets of Celexion, we own, co-own, or have exclusive rights to a number of patents and patent applications directed to various methods and compositions, including methods for identifying therapeutic antibodies and product candidates arising out of such entities’ technology platforms. In particular, we own patents and patent applications relating to our Retrocyte Display technology platform, a high throughput antibody expression platform for the identification of fully-human and humanized monoclonal antibodies. This patent family is projected to expire between 2029 and 2031. Through our acquisition of PhosImmune, we own, co-own, or have exclusive rights to patents and patent applications directed to various methods and compositions, including a patent directed to methods for identifying phosphorylated proteins using mass spectrometry. This patent is projected to expire in 2023. We also own patents and patent applications relating to the SECANT platform, a platform used for the generation of novel monoclonal antibodies. This patent family is projected to expire between 2028 and 2029. In addition, as we advance our research and development efforts with our institutional and corporate collaborators, we intend to seek patent protection for newly identified therapeutic antibodies and product candidates. We can provide no assurance that any of our patents, including the patents that were acquired or in-licensed in connection with our acquisitions of 4-AB, PhosImmune and certain assets of Celexion, will have commercial value, or that any of our existing or future patent applications, including the patent applications that were acquired or in-licensed in connection with our acquisitions of 4-AB, PhosImmune and certain assets of Celexion, will result in the issuance of valid and enforceable patents. Our issued patents covering Prophage vaccines and methods of use thereof, alone or in combination with other agents, expired or will expire at various dates between 2015 and 2024. In particular, our issued U.S. patents covering Prophage composition of matter expired in 2015. In addition, our issued patents covering QS-21 Stimulon composition of matter expired in 2008. We continue to explore means of extending the life cycle of our patent portfolio.

Various patents and patent applications have been exclusively licensed to us by the following entities:

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University of Virginia

In connection with our acquisition of PhosImmune in December 2015, we obtained exclusive rights to a portfolio of patent applications and one issued patent relating to PTTs under a patent license agreement with the University of Virginia (UVA). The UVA license gives us exclusive rights to develop and commercialize the PTT technology and an exclusive option to license any further PTT technology arising from ongoing research at UVA until December 2018. Under the license agreement, we will pay low to mid-single digit running royalties on net sales of PTT products, and a modest flat percentage of sublicensing income. In addition, we may be obligated to make milestone payments of up to $2.7 million for each indication of a licensed PTT product to complete clinical trials and achieve certain sales thresholds. The term of the UVA license agreement ends when the last of the licensed patents expires or becomes no longer valid. The UVA license agreement may be terminated as follows: (i) by UVA in connection with our bankruptcy or cessation of business relating to the licensed technology, (ii) by UVA if we commit a material, uncured breach or (iii) by us for our convenience on 180 days written notice.

Ludwig Institute for Cancer Research

On December 5, 2014, 4-AB entered into a license agreement with the Ludwig Institute for Cancer Research Ltd. (Ludwig), which replaced and superseded a prior agreement entered into between the parties in May 2011. Pursuant to the terms of the license agreement, Ludwig granted 4-AB an exclusive, worldwide license under certain intellectual property rights of Ludwig and Memorial Sloan Kettering Cancer Center arising from the prior agreement to further develop and commercialize GITR, OX40 and TIM-3 antibodies. On January 25, 2016, we and 4-AB entered into a second license agreement with Ludwig, on substantially similar terms, to develop CTLA-4 and PD-1 antibodies. Pursuant to the December 2014 license agreement, 4-AB made an upfront payment of $1.0 million to Ludwig. The December 2014 license agreement also obligates 4-AB to make potential milestone payments of up to $20.0 million for events prior to regulatory approval of licensed GITR, OX40 and TIM-3 products, and potential milestone payments in excess of $80.0 million if such licensed products are approved in multiple jurisdictions, in more than one indication, and certain sales milestones are achieved. Under the January 2016 license agreement, we are obligated to make potential milestone payments of up to $12.0 million for events prior to regulatory approval of CTLA-4 and PD-1 licensed products, and potential milestone payments of up to $32.0 million if certain sales milestones are achieved. Under each of these license agreements, we and/or 4-AB will also be obligated to pay low to mid-single digit royalties on all net sales of licensed products during the royalty period, and to pay Ludwig a percentage of any sublicensing income, ranging from a low to mid-double digit percentage depending on various factors. The license agreements may each be terminated as follows: (i) by either party if the other party commits a material, uncured breach; (ii) by either party if the other party initiates bankruptcy, liquidation or similar proceedings; or (iii) by 4-AB or us (as applicable) for convenience upon 90 days’ prior written notice. The license agreements also contain customary representations and warranties, mutual indemnification, confidentiality and arbitration provisions.

Mount Sinai School of Medicine

In November 1994, we entered into a patent license agreement with the Mount Sinai School of Medicine (the “Mount Sinai Agreement”). Through the Mount Sinai Agreement, we obtained an exclusive, worldwide license to patent rights relating to the heat shock protein technology that resulted from the research and development performed by Dr. Pramod Srivastava, our founding scientist and a former member of our Board of Directors. We agreed to pay Mount Sinai a royalty on the net sales of products covered by the licensed patent rights and also provided Mount Sinai with a 0.45% equity interest in the Company, or approximately 10,300 shares, valued at approximately $90,000 at the time of issuance. The term of the Mount Sinai Agreement ends when the last of the licensed patents expires in 2016 or becomes no longer valid.

University of Connecticut Health Center

In May 2001, we entered into a license agreement with the University of Connecticut Health Center (“UConn”) which was amended in March 2003 and June 2009. Through the license agreement, we obtained an exclusive, worldwide license to patent rights resulting from inventions discovered under a research agreement that was effective from February 1998 until December 2006. The term of the license agreement ends when the last of the licensed patents expires in 2024 or becomes no longer valid. UConn may terminate the agreement: (1) if, after 30 days written notice for breach, we continue to fail to make any payments due under the license agreement, or (2) we cease to carry on our business related to the patent rights or if we initiate or conduct actions in order to declare bankruptcy. We may terminate the agreement upon 90 days written notice. We are required to make royalty payments on any obligations created prior to the effective date of termination of the license agreement. Upon expiration or termination of the license agreement due to breach, we have the right to continue to manufacture and sell products covered under the license agreement which are considered to be works in progress for a period of six months. The license agreement contains aggregate milestone payments of approximately for each product we develop covered by the licensed patent rights. These milestone payments are contingent upon regulatory filings, regulatory approvals, and commercial sales of products. We have also agreed to pay UConn a royalty on the net sales of products covered by the license agreement as well as annual license maintenance fees beginning in May 2006. Royalties otherwise due on the net sales of products covered by the license agreement may be credited against the annual license maintenance

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fee obligations. Under the March 2003 amendment, we agreed to pay UConn an upfront payment and to make future payments for each patent or patent application with respect to which we exercised our option under the research agreement. As of December 31, 2015, we had paid approximately $745,000 to UConn under the license agreement. The license agreement gives us complete discretion over the commercialization of products covered by the licensed patent rights but also requires us to use commercially reasonable diligent efforts to introduce commercial products within and outside the United States. If we fail to meet these diligence requirements, UConn may be able to terminate the license agreement.

Regulatory Compliance

Governmental authorities in the United States and other countries extensively regulate the preclinical and clinical testing, manufacturing, labeling, storage, record keeping, advertising, promotion, export, marketing and distribution, among other things, of our investigational product candidates. In the United States, the FDA under the Federal Food, Drug, and Cosmetic Act, the Public Health Service Act and other federal statutes and regulations, subject pharmaceutical products to rigorous review.

In order to obtain approval of a new product from the FDA, we must, among other requirements, submit proof of safety and efficacy as well as detailed information on the manufacture and composition of the product. In most cases, this proof entails extensive preclinical, clinical, and laboratory tests. Before approving a new drug or marketing application, the FDA may also conduct pre-licensing inspections of the company, its contract research organizations and/or its clinical trial sites to ensure that clinical, safety, quality control, and other regulated activities are compliant with Good Clinical Practices, or GCP, or Good Laboratory Practices, or GLP, for specific non-clinical toxicology studies. The FDA may also require confirmatory trials, post-marketing testing, and extra surveillance to monitor the effects of approved products, or place conditions on any approvals that could restrict the commercial applications of these products. Once approved, the labeling, advertising, promotion, marketing, and distribution of a drug or biologic product must be in compliance with FDA regulatory requirements.

In Phase 1 clinical trials, the sponsor tests the product in a small number of patients or healthy volunteers, primarily for safety at one or more doses. Phase 1 trials in cancer are often conducted with patients who have end-stage or metastatic cancer. In Phase 2, in addition to safety, the sponsor evaluates the efficacy of the product in a patient population somewhat larger than Phase 1 trials. Phase 3 trials typically involve additional testing for safety and clinical efficacy in an expanded population at geographically dispersed test sites. The FDA may order the temporary or permanent discontinuation of a clinical trial at any time.

The sponsor must submit to the FDA the results of preclinical and clinical testing, together with, among other things, detailed information on the manufacture and composition of the product, in the form of a new drug application, or NDA, or in the case of biologics, like the Prophage vaccines, a biologics license application, or BLA. In a process that can take a year or more, the FDA reviews this application and, when and if it decides that adequate data are available to show that the new compound is both safe and effective for a particular indication and that other applicable requirements have been met, approves the drug or biologic for marketing.

Whether or not we have obtained FDA approval, we must generally obtain approval of a product by comparable regulatory authorities of international jurisdictions prior to the commencement of marketing the product in those jurisdictions. We are also subject to cGMP, GCP, and GLP compliance obligations and are subject to inspection by international regulatory authorities. International requirements may in some circumstances be more rigorous than U.S. requirements and may require additional investment in manufacturing process development, non-clinical studies, clinical studies, and record keeping that are not required for U.S. regulatory compliance or approval. The time required to obtain this approval may be longer or shorter than that required for FDA approval and can also require significant resources in time, money and labor.

Under the laws of the United States, the countries of the European Union and other nations, we and the institutions where we sponsor research are subject to obligations to ensure the protection of personal information of human subjects participating in our clinical trials. We have instituted procedures that we believe will enable us to comply with these requirements and the contractual requirements of our data sources. The laws and regulations in this area are evolving, and further regulation, if adopted, could affect the timing and the cost of future clinical development activities.

We are also subject to regulation under the Occupational Safety and Health Act, the Toxic Substances Control Act, the Resource Conservation and Recovery Act, and other current and potential future federal, state, or local regulations. Our research and development activities involve the controlled use of hazardous materials, chemicals, biological materials, various radioactive compounds, and for some experiments we use recombinant DNA. We believe that our procedures comply with the standards prescribed by local, state, and federal regulations; however, the risk of injury or accidental contamination cannot be completely eliminated. We conduct our activities in compliance with the National Institutes of Health Guidelines for Recombinant DNA Research.

Additionally, the U.S. Foreign Corrupt Practices Act, or FCPA, prohibits U.S. corporations and their representatives from offering, promising, authorizing or making payments to any foreign government official, government staff member, political party or political candidate in an attempt to obtain or retain business abroad. The scope of the FCPA includes interactions with certain healthcare professionals in many countries. Other countries have enacted similar anti-corruption laws and/or regulations.

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Competition

Competition in the pharmaceutical and biotechnology industries is intense. Many pharmaceutical or biotechnology companies have products on the market and are actively engaged in the research and development of products for the treatment of cancer.

Many competitors have substantially greater financial, manufacturing, marketing, sales, distribution, and technical resources, and more experience in research and development, clinical trials, and regulatory matters, than we do. Competing companies developing or acquiring rights to more efficacious therapeutic products for the same diseases we are targeting, or which offer significantly lower costs of treatment, could render our products noncompetitive or obsolete. See Part I-Item 1A. “Risk Factors-Risks Related to our Business-Our competitors may have superior products, manufacturing capability, selling and marketing expertise and/or financial and other resources.”

Academic institutions, governmental agencies, and other public and private research institutions conduct significant amounts of research in biotechnology, medicinal chemistry and pharmacology. These entities have become increasingly active in seeking patent protection and licensing revenues for their research results. They also compete with us in recruiting and retaining skilled scientific talent.

We have CPM antibody programs currently in early stage development targeting GITR, OX40, CTLA-4, LAG-3, TIM-3, PD-1, CEACAM1 and other undisclosed targets. We are aware of many companies that have antibody-based products on the market or in clinical development that are directed to the same biological target as some of our programs, including, without limitation, the following: (1) Bristol-Myers Squibb markets ipilimumab, an anti-CTLA-4 antibody, and nivolumab, an anti-PD-1 antibody, and is developing an anti-LAG-3 antibody and agonist to OX-40 (2) Merck has an approved anti-PD-1 antibody in the United States, and is developing an anti-GITR agonist and anti-CEACAM antibodies, (3) Ono Pharmaceuticals has an approved anti-PD-1 antibody in Japan, (4) AstraZeneca /Medimmune has anti-CTLA-4, OX-40 and PD1 antibodies in development, (5) Curetech has an anti-PD-1 antibody in development, (6) Pfizer has an anti-CTLA-4 antibody in development, (7) Tesaro has antibody programs targeting PD-1, TIM-3 and LAG-3, which include both monospecific and dual reactive antibody drug candidates, (8) Novartis has anti-PD-1 and anti-TIM-3 antibodies in discovery, and anti-LAG-3 and GITR agonist in clinical trials and (9) Roche/Genetech has an anti-OX40 agonist in development. There is no guarantee that our antibody product candidates will be able to compete with our competitors’ antibody products and product candidates.

We have autologous vaccines programs in development including our Prophage vaccine in clinical development for GBM and our neo-antigen based AutoSynVax vaccine in preclinical development. We are aware of many companies pursuing cancer vaccines and/or immunotherapies clinical development, including, without limitation, the following: (1) Neon Therapeutics is developing a personalized neoantigen vaccine; (2) Gritstone Oncology is discovering and developing a novel tumor-specific neo-antigen (TSNA) based immunotherapies, with an initial focus on lung cancer; (3)Aduro Biotech and Advaxis Inc. are developing immunotherapy platforms (Listeria, cyclic dinucleotides, and B-select antibodies); (4) Inovio Pharmaceutical Inc. and Medimmune are collaborating on developing DNA based immunotherapies for cancer and infectious disease; (5) Oncolytics Biotech Inc. is developing oncolytic virus based cancer therapeutics in lung, colorectal and pancreatic cancers; and (6) Oncothyreon is developing synthetic vaccines for cancer therapeutics.

Several companies have products that utilize similar technologies and/or patient-specific medicine techniques that compete with our HSP based vaccines. For treatment of recurrent glioma, Roche markets bevacizumab and Eisai and Arbor Pharmaceuticals market carmustine. Schering Corporation, a subsidiary of Merck, markets temozolmide for treatment of patients with ndGBM and refractory astrocytoma. Other companies are developing vaccines for the treatment of patients with newly diagnosed glioma, such as Innocell Corp (Immuncell-LC), ImmunoCellular Therapeutics (ICT-107), Northwest Biotherapeutics (DC-Vax), Immatics (IMA-950) and Activartis Biotech (GBM-Vax).

We are aware of compounds that claim to be comparable to QS-21 Stimulon that are being used in clinical trials. Several other vaccine adjuvants are in development and could compete with QS-21 Stimulon for inclusion in vaccines in development. These adjuvants include, but are not limited to, (1) oligonucleotides, under development by Pfizer, Idera, Colby, and Dynavax, (2) MF59, under development by Novartis, (3) IC31, under development by Intercell, and (4) MPL, under development by GSK. In the past, we have provided QS-21 Stimulon to other entities under materials transfer arrangements. In at least one instance, it is possible that this material was used unlawfully to develop synthetic formulations and/or derivatives of QS-21. In addition, companies such as Adjuvance Technologies, Inc., CSL Limited, and Novavax, Inc., as well as academic institutions and manufacturers of saponin extracts, are developing saponin adjuvants, including derivatives and synthetic formulations. These sources may be competitive to our ability to execute future partnering and licensing arrangements involving QS-21 Stimulon. The existence of products developed by these and other competitors, or other products of which we are not aware or which other companies may develop in the future, may adversely affect the marketability of products developed or sold using QS-21 Stimulon.

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We are also aware of a third party that manufactures pre-clinical material purporting to be comparable to QS-21 Stimulon. The claims being made by this third party may create marketplace confusion and have an adverse effect on the goodwill generated by us and our partners with respect to QS-21 Stimulon. Any diminution of this goodwill may have an adverse effect on our ability to commercialize future products, if any, incorporating this technology, either alone or with a third party.

We anticipate that we will face increased competition in the future as new companies enter markets we seek to address and scientific developments surrounding immunotherapy and other traditional cancer and infectious disease therapies continue to accelerate.

Employees

As of February 29, 2016, we had 230 employees, of whom 70 were PhDs and four were MDs. None of our employees are subject to a collective bargaining agreement. We believe that we have good relations with our employees.

Corporate History

Antigenics L.L.C. was formed as a Delaware limited liability company in 1994 and was converted to Antigenics Inc., a Delaware corporation, in February 2000 in conjunction with our initial public offering of common stock. On January 6, 2011, we changed our name from Antigenics Inc. to Agenus Inc.

Availability of Periodic SEC Reports

Our Internet website address is www.agenusbio.com. We make available free of charge through our website our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (“Exchange Act”), as soon as reasonably practicable after we electronically file such material with, or furnish such material to, the Securities and Exchange Commission (the “SEC”). The contents of our website are not part of, or incorporated into, this document. In addition, we regularly use our website to post information regarding our business, product development programs and governance, and we encourage investors to use our website, particularly the information in the sections entitled “Financial” and “News,” as sources of information about us.

The public may read and copy any materials filed by Agenus with the SEC at the SEC's Public Reference Room at 100 F Street, NE, Room 1580, Washington, DC 20549.  The public may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at www.sec.gov.

The contents of the websites referred to above are not incorporated into this filing. Further, our references to the URLs for these websites are intended to be inactive textual references only.

Our future operating results could differ materially from the results described in this Annual Report on Form 10-K due to the risks and uncertainties described below. You should consider carefully the following information about risks below in evaluating our business. If any of the following risks actually occur, our business, financial conditions, results of operations and future growth prospects would likely be materially and adversely affected. In these circumstances, the market price of our common stock would likely decline.

We cannot assure investors that our assumptions and expectations will prove to be correct. Important factors could cause our actual results to differ materially from those indicated or implied by forward-looking statements. See “Note Regarding Forward-Looking Statements” in this Annual Report on Form 10-K. Factors that could cause or contribute to such differences include those factors discussed below.

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Risks Related to our Business

If we incur operating losses for longer than we expect, or we are not able to raise additional capital, we may be unable to continue our operations, or we may become insolvent.

Our net losses for the years ended December 31, 2015, 2014, and 2013, were $87.9 million, $42.5 million, and $30.1 million, respectively. We expect to incur additional losses over the next several years as we continue to research and develop our technologies and pursue partnering opportunities, regulatory strategies, commercialization, and related activities. Furthermore, our ability to generate cash from operations is dependent on the success of our licensees and collaboration partners, as well as the likelihood and timing of new strategic licensing and partnering relationships and/or successful development and commercialization of product candidates, including through our collaboration with Incyte, our HSP-based vaccines, and vaccines containing QS-21 Stimulon^® adjuvant.

On December 31, 2015, we had $171.7 million in cash and cash equivalents and short-term investments. We believe that, based on our current plans and activities, our working capital resources at December 31, 2015, will be sufficient to satisfy our liquidity requirements through the first half of 2017. We expect to attempt to secure additional funds before our current funds are depleted although additional funding may not be available on favorable terms, or at all.

To date, we have financed our operations primarily through the sale of equity and debt securities. In order to finance future operations going forward, we will be required to raise additional funds in the capital markets, through arrangements with collaboration partners or from other sources. Additional financing may not be available on favorable terms, or at all. If we are unable to raise additional funds when we need them or if we incur operating losses for longer than we expect, we may not be able to continue some or all of our operations, or we may become insolvent. We also may be forced to license or sell technologies to others under agreements that are on unfavorable terms or allocate to third parties substantial portions of the potential value of these technologies.

There are a number of factors that will influence our future capital requirements, including, without limitation, the following:

General economic conditions in the United States economy and abroad may have a material adverse effect on our liquidity and financial condition, particularly if our ability to raise additional funds is impaired. The ability of potential patients and/or health care payers to pay for our future products, if any, could also be adversely impacted, thereby limiting our potential revenue. In addition, any negative impacts from any deterioration in the credit markets on our collaboration partners could limit potential revenue from our product candidates.

Our and our subsidiaries’ obligations related to our monetization of royalties payable to us by GSK in respect of its shingles vaccine, HZ/su, along with our 2015 Subordinated Notes, could materially and adversely affect our liquidity.

In September 2015, we and our wholly-owned subsidiary, Antigenics LLC (“Antigenics”), entered into the Note Purchase Agreement with Oberland Capital SA Zermatt LLC, as collateral agent, an affiliate of Oberland as the lead purchaser and certain other purchasers, pursuant to which Antigenics issued $100.0 million aggregate principal amount of limited recourse notes (the “Notes”) to the purchasers. Antigenics has the option to issue an additional $15.0 million aggregate principal amount of Notes (the “Additional Notes”) to the purchasers within 15 days after approval of GSK’s shingles vaccine, HZ/su, by the FDA, provided such approval occurs on or before June 30, 2018. The Notes accrue interest at a rate of 13.5% per annum, compounded quarterly, from and after September 8, 2015 (the “Closing Date”). Principal and interest payments are due on each of March 15, June 15, September 15 and December 15, and shall be made solely from the royalties paid from GSK to Antigenics on sales of GSK’s shingles and malaria

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vaccines. GSK will send all royalty payments to a segregated bank account, and to the extent there are insufficient royalties deposited into the account to fund a quarterly interest payment, the interest will be capitalized and added to the aggregate principal balance of the loan. The final legal maturity date of the Notes is the earlier of (i) the 10th anniversary of the first commercial sale of GSK’s shingles or malaria vaccines and (ii) September 8, 2030 (the “Maturity Date”).

On September 8, 2018, each purchaser has the option to require Antigenics to repurchase up to 15% of the Notes issued to such purchaser on the Closing Date (the “Put Notes”) at a purchase price equal to the principal amount thereof plus accrued and unpaid interest thereon (the “Put Payment”). On the earlier of (i) September 8, 2027 and (ii) the Maturity Date, Antigenics is required to pay the purchasers an amount equal to the following (the “Make-Whole Payment”): $100.0 million (or $115.0 million if the Additional Notes are sold) minus the aggregate amount of all payments made in respect of the Notes (regardless of whether characterized as principal or interest at the time of payment), including the original principal amount of any repaid Put Notes.

The Note Purchase Agreement specifies a number of events of default (some of which are subject to applicable cure periods), including (i) failure to cause royalty payments to be deposited into the segregated bank account, (ii) payment defaults, (iii) breaches of representations and warranties made at the time the Notes were, or the Additional Notes are, issued, (iv) covenant defaults, (v) a final and unappealable judgment against Antigenics for the payment of money in excess of $1.0 million, (vi) bankruptcy or insolvency defaults, (vii) the failure to maintain a first-priority perfected security interest in the collateral in favor of the collateral agent and (viii) the occurrence of a change of control of Agenus. Upon the occurrence of an event of default, subject to cure periods in certain circumstances and some limited exceptions, the collateral agent may declare the Notes immediately due and payable, in which case Antigenics would owe a payment equal to the following (the “Accelerated Default Payment”): the outstanding principal amount of the Notes, plus all accrued and unpaid interest thereon, plus a premium payment that would yield an aggregate internal rate of return (“IRR”) for the purchasers as follows: (i) an IRR of 20% if the event of default occurs within 24 months of the Closing Date, (ii) an IRR of 17.5% if the event of default occurs after 24 months but within 48 months of the Closing Date, and (iii) an IRR of 15% if the event of default occurs more than 48 months after the Closing Date. Upon the occurrence and during the continuance of any event of default, interest on the Notes also increases by 2.5% per annum.

We are a party to the Note Purchase Agreement as a guarantor of Antigenics, and we generally guarantee the Put Payment, the Make-Whole Payment and the Accelerated Default Payment. If we are obligated to make the Put Payment or the Make-Whole Payment, our liquidity would be materially and adversely affected. If we or Antigenics default on the Notes and we are obligated to pay the Accelerated Default Payment, our liquidity would be materially and adversely affected. Satisfaction of the Notes will depend upon the future sales of GSK’s shingles and malaria vaccines, if approved, and, if we are obligated to make the Put Payment, the Make-Whole Payment or the Accelerated Default Payment, our future performance, which is subject to many factors, including the factors identified in this “Risk Factors” section and other factors beyond our control.

In February 2015, we exchanged senior subordinated promissory notes that we issued in 2013 for new senior subordinated promissory notes in the aggregate principal amount of $5.0 million with annual interest at 8%, and we issued an additional $9.0 million principal amount of such notes, or the 2015 Subordinated Notes. The 2015 Subordinated Notes are due February 2018 and include default provisions that allow for the acceleration of the principal payment of the 2015 Subordinated Notes in the event we become involved in certain bankruptcy proceedings, become insolvent, fail to make a payment of principal or (after a grace period) interest on the 2015 Subordinated Notes, default on other indebtedness with an aggregate principal balance of $13.5 million or more if such default has the effect of accelerating the maturity of such indebtedness, or become subject to a legal judgment or similar order for the payment of money in an amount greater than $13.5 million if such amount will not be covered by third-party insurance. If we default on the 2015 Subordinated Notes and the repayment of such indebtedness is accelerated, our liquidity could be materially and adversely affected.

If we do not have sufficient cash on hand to pay any of the Put Payment, the Make-Whole Payment or the Accelerated Default Payment when due, or to otherwise service our 2015 Subordinated Notes, we may be required, among other things, to:

Such measures might not be sufficient to enable us to make principal and interest payments. In addition, any such financing, refinancing, or sale of assets might not be available on favorable terms, if at all.

We are dependent upon our collaboration with Incyte to further develop, manufacture and commercialize CPM antibodies against certain targets. If we or Incyte fail to perform as expected, the potential for us to generate future revenues under the

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collaboration would be significantly reduced, the development and/or commercialization of these CPM antibodies may be terminated or substantially delayed, and our business would be severely harmed.

Under the terms of our collaboration agreement with Incyte, we and Incyte have a joint steering committee that oversees and manages worldwide regulatory, development, manufacturing, and commercialization activities for our CPM antibody product candidates pursuant to the collaboration agreement with equal representation from both parties. For each program, we serve as the lead for pre-clinical development activities through the filing of an investigational new drug application, or IND, and Incyte serves as the lead for clinical development activities. Accordingly, the timely and successful completion by Incyte of clinical development activities will significantly affect the timing and amount of any revenues we may receive under the collaboration agreement. Incyte’s activities will be influenced by, among other things, the efforts and allocation of resources by Incyte, which we cannot control. If Incyte does not perform in the manner we expect or fulfill its responsibilities in a timely manner, or at all, the clinical development, manufacturing, regulatory approval, and commercialization efforts related to CPM antibodies under the collaboration could be delayed or terminated, and it could become necessary for us to assume the responsibilities for the clinical development, manufacturing, regulatory approval or commercialization of the CPM antibodies at our own expense. Accordingly, there can be no assurance that any of the development, regulatory or sales milestones will be achieved, that we will receive any future milestone or royalty payments under the collaboration agreement, or that we will share in any revenues under the collaboration agreement.

Each program in the collaboration falls under either (i) a cost sharing model, in which we share all costs and profits on a 50:50 basis with Incyte and we are eligible for potential milestones, or (ii) a royalty-bearing model, in which Incyte funds 100% of the costs, with Agenus eligible for potential milestones and royalties. Incyte has far greater resources than us, and it may be difficult for us to meet our obligation to fund 50% of all costs for the cost-sharing programs, including the GITR and OX40 programs. Moreover, clinical programs under the collaboration could be accelerated due to better than expected clinical outcomes, thus requiring us to spend more money than anticipated on a given program and in a shorter period of time. We can elect to cease sharing costs 50:50 and convert the arrangements to royalty-bearing on twelve months prior written notice. If we fail to meet this notice obligation and do not meet our funding commitments, we would be in breach of our obligations under the agreement.  

In addition, our collaboration with Incyte may be unsuccessful due to other factors, including, without limitation, the following:

If Incyte terminates our collaboration agreement, we would need to raise additional capital and may need to identify and come to agreement with another collaboration partner to advance our CPM programs. Even if we are able to find another partner, this effort could cause delays in our timelines and/or additional expenses, which could adversely affect our business prospects and the future of our CPM antibody product candidates.

Our CPM programs are in early stage development, and there is no guarantee that we will be successful in advancing from CPM antibody product candidates through clinical development.

Our CPM programs are currently in early stage development, and the majority of our CPM programs are pre-clinical. Even if our pre-clinical studies or Phase 1 trials produce positive results, they may not necessarily be predictive of the results of future clinical trials in humans. Many companies in the pharmaceutical, biopharmaceutical and biotechnology industries have suffered significant setbacks in clinical trials after achieving positive results in pre-clinical development or Phase 1 trials, and we cannot be certain that we will not face similar setbacks. These setbacks have been caused by, among other things, pre-clinical findings made while clinical trials were underway or safety or efficacy observations made in clinical trials, including adverse events. Moreover, pre-clinical and clinical data are often susceptible to varying interpretations and analyses, and many companies that believed their product candidates performed satisfactorily in pre-clinical studies and clinical trials nonetheless failed to obtain regulatory approval. If we fail to produce positive results in future clinical trials of CPM antibodies, our business and financial prospects would be materially adversely affected.

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We are undergoing significant growth across multiple locations, and we may encounter difficulties in managing this growth, which could disrupt our operations.

As of February 29, 2016 we had 230 employees.  From January 1, 2014 to February 29, 2016, we added 162 new employees, 69 of whom are employees of our wholly-owned subsidiary 4-Antibody AG (4-AB) that we acquired in February 2014, and 28 of whom are employees of our wholly-owned subsidiary Agenus West, LLC who joined us in connection with our acquisition of XOMA Corporation’s antibody manufacturing pilot plant in December 2015. In addition, through various acquisitions, we have expanded our research and development activities both nationally and internationally to California, Virginia, Switzerland, Germany and the United Kingdom. We expect to continue increasing our headcount as we continue to build our research and development capabilities and integrate our acquired technology platforms. To manage this growth and expansion, we must continue to implement and improve our managerial, operational and financial systems and continue to recruit, train and retain qualified personnel. If our management is unable to effectively manage our growth, our expenses may increase more than expected, our ability to generate revenue could be reduced, and we may not be able to implement our business strategy.

We may not receive anticipated QS-21 Stimulon revenues from our licensees.

We currently rely upon and expect to continue to rely upon our third party licensee, GSK, to develop, test, market and manufacture vaccines that utilize our QS-21 Stimulon adjuvant. Our other licensee, Janssen Science Ireland UC, recently notified us that they were terminating their license for use of QS-21 Stimulon.

GSK owns their product development process, and we cannot predict their requirements for QS-21 Stimulon in the future or to what extent, if any, they will develop and commercialize vaccines that use QS-21 Stimulon as an adjuvant. GSK may initiate or terminate programs containing QS-21 Stimulon at any time. In addition, even if GSK successfully completes clinical trials with vaccine candidates using QS-21 Stimulon or these vaccine candidates receive positive decisions from regulatory bodies, there is no guarantee that these products will ultimately obtain regulatory approval or, if so approved, will have a successful commercial launch or generate any future milestones or royalty payments. In September 2015, we entered into the Note Purchase Agreement and partially monetized the potential royalties we are entitled to receive from GSK on future sales of its shingles and malaria vaccines, if any. All of the royalties that are payable to us from GSK on sales of these products candidates, if any, will be used entirely to satisfy our obligations to the purchasers of the Notes. However, there is no guarantee that GSK’s shingles and malaria vaccines will be approved in any territories for which they seek regulatory approval. Even if GSK’s shingles and/or malaria vaccines are approved, there is no guarantee that GSK will have a successful commercial launch of either product or generate any revenues from sales to help satisfy our obligations under the Note Purchase Agreement. Any inability to receive anticipated revenues, or a reduction in revenues, generated from QS-21 Stimulon could have a material adverse effect on our business, financial condition and results of operations.

Our synthetic HSP peptide-based platform is in early stage development, and there is no guarantee that a product candidate will progress from this platform.

In June 2014, we reported positive results from a Phase 2 trial with HerpV^TM, a vaccine candidate for genital herpes from our synthetic HSP peptide-based platform. While the HerpV Phase 2 trial met its formal endpoints, it was unclear whether the magnitude of the effect on viral load would be sufficient to significantly reduce the incidence, severity, or duration of herpetic lesions or reduce the risk of viral transmission. We do not expect to advance this program into a Phase 3 trial, but we have initiated our AutoSynVax™ synthetic cancer vaccine program based on our prior findings with this platform. Although we are targeting to initiate clinical trials for our first AutoSynVax product candidate in the second half of 2016, there is no guarantee that we will be able to do so. There is no guarantee that a product candidate will progress from this platform at all or that results of any potential future clinical trials will be positive. Furthermore, it is possible that research and discoveries by others will render any product candidate from this platform as obsolete or noncompetitive.

We may not be able to advance clinical development or commercialize Prophage^TM vaccines or realize any benefits from this program.

The probability of future clinical development efforts leading to marketing approval and commercialization of Prophage vaccines is highly uncertain. Prophage vaccines have been in clinical development for over 15 years, including multiple Phase 1 and 2 trials in eight different tumor types as well as randomized Phase 3 trials in metastatic melanoma and adjuvant renal cell carcinoma. To date, none of our clinical trials with Prophage vaccines have resulted in a marketing approval, except in Russia where commercialization of the approved product was unsuccessful. Although we are targeting to initiate our next Prophage clinical trial in ndGBM in the second half of 2016, there is no guarantee that we will be able to do so. In addition, while we believe Prophage vaccines may provide clinical benefit to some patients as a monotherapy and in combination with other therapies, there is no guarantee that, if completed, subsequent Prophage trials would yield useful translational and/or efficacy data.

We do not currently sponsor any of the on-going clinical trials with Prophage vaccines and therefore we lack the ability to control trial design, timelines, and data availability. Current and future studies may eventually be terminated due to, among other

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things, slow enrollment, lack of probability that they will yield useful translational and/or efficacy data, lengthy timelines, or the unlikelihood that results will support timely or successful regulatory filings. Currently, the only actively enrolling Prophage vaccine clinical trial is a Phase 2 trial of Prophage vaccine in combination with bevacizumab in patients with surgically resectable recurrent glioma. This trial is being conducted under the sponsorship of the Alliance for Clinical Trials in Oncology, a cooperative group of the National Cancer Institute (NCI). While the NCI Alliance has confirmed a commitment to completion of the trial, to date, clinical site activation and patient enrollment have not met expectations, which could curtail the viability of sustaining the trial. Furthermore, potential changes in clinical practices trending away from the administration of bevacizumab for the treatment of recurrent glioma could exacerbate enrollment issues and/or render the trial design impractical. Lastly, the NCI operationalization of the clinical trial includes limited onsite training for tumor tissue procurement, which may result in improper tissue handling and increase the risk of vaccine manufacturing failures.

Changes in our manufacturing strategies, manufacturing problems, or increased demand may cause delays, unanticipated costs, or loss of revenue streams within or across our programs.

Our CPM antibody programs, including those partnered with Incyte, will require substantial manufacturing development and investment to progress. We are currently progressing a portfolio of CPM antibody programs that are at different stages of development. If these efforts are delayed or do not produce the desired outcomes, this will cause delays in development timelines and increased costs, which may cause us to limit the size and scope of our efforts and studies. Although we recently secured our own antibody manufacturing capabilities with the purchase of a manufacturing pilot plant from XOMA Corporation, we only expect this facility to provide us with antibody supply requirements through clinical proof-of-concept studies and not for larger, registrational studies or any commercial supply requirements. Furthermore, we currently still rely on contract manufacturing organizations (“CMOs”) and contract research organizations (“CROs”) to support some of our existing CPM antibody programs. Our dependence on external CMOs for the manufacture of certain antibodies results in intrinsic risks to our performance, timelines, and costs of our accelerated development plans. We may also need to develop or secure later phase and/or commercial manufacturing capabilities, all of which would cause us to incur additional costs and risk, and which could divert resources away from our CPM antibody programs and/or lead to delays in the development of our product candidates. In the event that our CPM antibody programs require progressively larger production capabilities, our options for qualified CMOs may become more limited.

The long-term success of the antibody pilot plant manufacturing facility and capabilities that we acquired from XOMA Corporation will depend, in part, on our ability to realize the anticipated synergies, business opportunities and growth prospects from combining our manufacturing facilities in Lexington, MA with the antibody pilot plant manufacturing facility in Berkeley, CA. We may never realize these anticipated synergies, business opportunities and growth prospects. Assumptions underlying estimates of expected cost savings as a result of the acquisition of the antibody pilot plant manufacturing facility may be inaccurate. If any of these factors limit our ability to successfully manufacture CPM antibodies to support our planned clinical trials, the expectations of future results of operations, including certain cost savings and synergies expected to result from the acquisition of XOMA Corporation’s antibody pilot plant manufacturing facility, might not be met.

We currently manufacture our Prophage vaccines in our Lexington, MA facility. Manufacturing of the Prophage vaccines is complex, and various factors could cause delays or an inability to supply the vaccine. Deviations in the processes controlling manufacture or deficiencies in size or quality of source material could result in production failures. In addition, regulatory bodies may require us to make our manufacturing facility a single product facility. In such an instance, we would no longer have the ability to manufacture Prophage vaccines in addition to other product candidates in our current facility.

We have given our corporate QS-21 Stimulon licensee, GSK, manufacturing rights for QS-21 Stimulon for use in their product programs. If GSK or its third party CMO encounters problems with QS-21 Stimulon manufacturing, any of their programs containing QS-21 Stimulon could be delayed or terminated, and this could have an adverse effect on our potential license fees, milestone payments and royalties that we may otherwise receive from these programs and use to satisfy our obligations under the Note Purchase Agreement. We have retained the right to manufacture QS-21 for ourselves and third parties, although no other such programs are anticipated to bring us substantial revenues in the near future, if ever.

Our ability to efficiently manufacture our product candidates is contingent, in part, upon our own, and our CMOs’ ability to ramp up production in a timely manner without the benefit of years of experience and familiarity with the processes, which we may not be able to adequately transfer. We currently rely upon and expect to continue to rely upon third parties, potentially including our collaborators or licensees, to produce materials required to support our product candidates, pre-clinical studies, clinical trials, and any future commercial efforts. A number of factors could cause production interruptions at either our manufacturing facility or the facilities of our CMOs or suppliers, including equipment malfunctions, labor or employment retention problems, natural disasters, power outages, terrorist activities, or disruptions in the operations of our suppliers. Alternatively, there is the possibility we may have excess manufacturing capacity if product candidates do not progress as planned.

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As mentioned above, reliance on third-party manufacturers entails risks to which we would not be subject if we manufactured all of our product candidates ourselves, including reliance on the third party for regulatory compliance, the possibility of breach of the manufacturing agreement by the third party because of factors beyond our control, and the possibility of termination or non-renewal of the agreement by the third party, based on its own business priorities, at a time that is costly or inconvenient for us.

Biopharmaceutical manufacturing is also subject to extensive government regulation. Components of a finished therapeutic product approved for commercial sale or used in late-stage clinical trials must be manufactured in accordance with current good manufacturing practices or cGMP. These regulations govern manufacturing processes and procedures (including record keeping) and the implementation and operation of quality systems to control and assure the quality of investigational products and products approved for sale. Our facilities and quality systems and the facilities and quality systems of some or all of our third party contractors must pass a pre-approval inspection for compliance with the applicable regulations as a condition of regulatory approval of a product candidate. In addition, facilities are subject to on-going inspections, and minor changes in manufacturing processes may require additional regulatory approvals, either of which could cause us to incur significant additional costs and lose revenue.

Risks associated with doing business internationally could negatively affect our business.

We have research and development operations in Switzerland, Germany and the United Kingdom. We expect to pursue pathways to develop and commercialize our product candidates in both U.S. non-U.S. jurisdictions. Various risks associated with foreign operations may impact our success. Possible risks of foreign operations include fluctuations in the value of foreign and domestic currencies requirements to comply with various jurisdictional requirements such as data privacy regulations, disruptions in the import, export, and transportation of patient tumors and our products or product candidates, the product and service needs of foreign customers, difficulties in building and managing foreign relationships, the performance of our licensees or collaborators, geopolitical instability, unexpected regulatory, economic, or political changes in foreign markets and limitations on the flexibility of our operations and costs imposed by local labor laws. For example, in 2008 our Oncophage^® vaccine was approved for sale in Russia, but we have never received, and do not expect to receive, any revenues from sales in Russia. See “Risk Factors- Even if we receive marketing approval for our product candidates, such product approvals could be subject to restrictions or withdrawals. Regulatory requirements are subject to change. Further, even if we receive marketing approval, we may not receive sufficient coverage and adequate reimbursement for our products.”

Our competitors may have superior products, manufacturing capability, selling and marketing expertise and/or financial and other resources.

Our product candidates and the product candidates in development by our collaboration partners may fail because of competition from major pharmaceutical companies and specialized biotechnology companies that market products, or that are engaged in the development of product candidates, directed at cancer, infectious diseases and degenerative disorders. Many of our competitors, including large pharmaceutical companies, have greater financial and human resources and more experience than we do. Our competitors may:

There is no guarantee that our product candidates will be able to compete with potential future products being developed by our competitors.

We have CPM antibody programs currently in early stage development targeting GITR, OX40, CTLA-4, LAG-3, TIM-3, PD-1 and CEACAM1. We are aware of many companies that have antibody-based products on the market or in clinical development that are directed to the same biological target as some of our programs, including, without limitation, the following: (1) Bristol-Myers Squibb markets ipilimumab, an anti-CTLA-4 antibody, and nivolumab, an anti-PD-1 antibody, and is developing an anti-LAG-3 antibody and agonist to OX-40 (2) Merck has an approved anti-PD-1 antibody in the United States, and is developing an anti-GITR agonist and anti-CEACAM antibodies, (3) Ono Pharmaceuticals has an approved anti-PD-1 antibody in Japan, (4) AstraZeneca

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/Medimmune has anti-CTLA-4, OX-40 and PD1 antibodies in development, (5) Curetech has an anti-PD-1 antibody in development, (6) Pfizer has an anti-CTLA-4 antibody in development, (7) Tesaro has antibody programs targeting PD-1, TIM-3 and LAG-3, which include both monospecific and dual reactive antibody drug candidates, (8) Novartis has anti-PD-1 and anti-TIM-3 antibodies in discovery, and anti-LAG-3 and GITR agonist in clinical trials and (9) Roche/Genetech has an anti-OX40 agonist in development. There is no guarantee that our antibody product candidates will be able to compete with our competitors’ antibody products and product candidates.

We have autologous vaccines programs in development including our Prophage vaccine in clinical development for GBM and our neo-antigen based AutoSynVax vaccine in preclinical development.  We are aware of many companies pursuing cancer vaccines and/or immunotherapies in clinical development, including, without limitation, the following: (1) Neon Therapeutics is developing a personalized neoantigen vaccine; (2) Gritstone Oncology is discovering and developing a novel tumor-specific neo-antigen (TSNA) based immunotherapies, with an initial focus on lung cancer; (3) Aduro Biotech is developing immunotherapy platforms (Listeria, cyclic dinucleotides, and B-select antibodies); (4) Inovio Pharmaceutical Inc. and Medimmune are collaborating on developing DNA-based immunotherapies for cancer and infectious disease; (5) Oncolytics Biotech Inc. is developing oncolytic virus based cancer therapeutics in lung, colorectal and pancreatic cancers; and (6) Oncothyreon is developing synthetic vaccines for cancer therapeutics.

We are aware of compounds that claim to be comparable to QS-21 Stimulon that are being used in clinical trials. Several other vaccine adjuvants are in development and could compete with QS-21 Stimulon for inclusion in vaccines in development. These adjuvants include, but are not limited to, (1) oligonucleotides, under development by Pfizer, Idera, Colby, and Dynavax, (2) MF59, under development by Novartis, (3) IC31, under development by Intercell, and (4) MPL, under development by GSK. In the past, we have provided QS-21 Stimulon to other entities under materials transfer arrangements. In at least one instance, it is possible that this material was used unlawfully to develop synthetic formulations and/or derivatives of QS-21. In addition, companies such as Adjuvance Technologies, Inc., CSL Limited, and Novavax, Inc., as well as academic institutions and manufacturers of saponin extracts, are developing saponin adjuvants, including derivatives and synthetic formulations. These sources may be competitive to our ability to execute future partnering and licensing arrangements involving QS-21 Stimulon. The existence of products developed by these and other competitors, or other products of which we are not aware or which other companies may develop in the future, may adversely affect the marketability of products we and our partners develop.

We are also aware of a third party that manufactures pre-clinical material purporting to be comparable to QS-21 Stimulon. The claims being made by this third party may create marketplace confusion and have an adverse effect on the goodwill generated by us and our partners with respect to QS-21 Stimulon. Any diminution of this goodwill may have an adverse effect on our ability to commercialize future products, if any, incorporating this technology, either alone or with a third party.

In competition with our Prophage product candidates, Genentech markets bevacizumab, and Eisai and Arbor Pharmaceuticals market carmustine. In addition, TVAX Biomedical and Stemline Therapeutics are developing immunotherapy candidates TVI-Brain-1 and SL-701, respectively, for recurrent glioma. Other companies are developing vaccine candidates for the treatment of patients with newly diagnosed glioma, such as ImmunoCellular Therapeutics (ICT-107), Northwest Biotherapeutics (DC-Vax), Immatics (IMA-950), Activartis Biotech (GBM-Vax), Annias Immunotherapeutics (CMV Vaccine) and Celldex (CDX-110). Other companies may begin development programs as well.

As we develop our vaccines, such as Prophage and AutoSynVax, in other indications or in combination with other product candidates, such as available standard of care agents (Avastin^®), or with CPMs, they could face additional competition in those indications or in those combinations. In addition, and prior to regulatory approval, if ever, our vaccines and our other product candidates may compete for access to patients with other products in clinical development, with products approved for use in the indications we are studying, or with off-label use of products in the indications we are studying. We anticipate that we will face increased competition in the future as new companies enter markets we seek to address and scientific developments surrounding immunotherapy and other traditional cancer therapies continue to accelerate.

Failure to capture the anticipated benefits or our strategic acquisitions and licensing transactions could adversely affect our business, operations and financial condition.

An important part of our business strategy to date has been to identify and advance a pipeline of product candidates by acquiring and in-licensing product candidates, technologies and businesses that we believe are a strategic fit with our existing business. Since we acquired 4-AB in February 2014, we have completed numerous additional strategic acquisitions and licensing transactions. The ultimate success of these strategic transactions entails numerous operational and financial risks, including:

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We have limited resources to integrate acquired and in-licensed product candidates, technologies and businesses into our current infrastructure, and we may fail to realize the anticipated benefits of our strategic transactions. Any such failure could have an adverse effect on our business, operations and financial condition.

Failure to enter into and/or maintain significant licensing, distribution and/or collaboration agreements on favorable terms to us may hinder or cause us to cease our efforts to develop and commercialize our product candidates, increase our development timelines, and/or increase our need to rely on partnering or financing mechanisms, such as sales of debt or equity securities, to fund our operations and continue our current and anticipated programs.

As previously noted, our ability to advance our CPM programs depends in part on collaboration agreements such as our collaboration with Incyte. See “Risk Factors—Risks Related to Our Business—We are dependent upon our collaboration with Incyte to further develop, manufacture and commercialize CPM antibodies against certain targets using our proprietary antibody discovery platforms. If we or Incyte fail to perform as expected, the potential for us to generate future revenues under the collaboration would be significantly reduced, the development and/or commercialization of these CPM antibodies may be terminated or substantially delayed, and our business would be severely harmed.” In addition, from time to time we engage in efforts to enter into licensing, distribution and/or collaboration agreements with one or more pharmaceutical or biotechnology companies to assist us with development and/or commercialization of our other product candidates. If we are successful in entering into such agreements, we may not be able to negotiate agreements with economic terms similar to those negotiated by other companies. We may not, for example, obtain significant upfront payments, substantial royalty rates or milestones. If we fail to enter into any such agreements, our efforts to develop and/or commercialize our product candidates may be undermined. In addition, if we do not raise funds through any such agreements, we will need to rely on other financing mechanisms, such as sales of debt or equity securities, to fund our operations. Such financing mechanisms, if available, may not be sufficient or timely enough to advance our programs forward in a meaningful way in the short-term.

While we have been pursuing these business development efforts for several years for our Prophage vaccine, we have not entered into a substantial agreement other than the agreement with NewVac to sell Oncophage in Russia, which was unsuccessful and expired in 2014. In addition, other companies may not be interested in pursuing patient-specific vaccines like our Prophage vaccines, and many other companies have been and may continue to be unwilling to commit to an agreement prior to receipt of additional clinical data, if at all.

Because we rely on collaborators and licensees for the development and commercialization of many of our product candidate programs, these programs may not prove successful, and/or we may not receive significant payments from such parties.

Part of our strategy is to develop and commercialize many of our product candidates by continuing or entering into arrangements with academic, government, or corporate collaborators and licensees. Our success depends on our ability to negotiate such agreements on favorable terms and on the success of the other parties in performing research, pre-clinical and clinical testing, completing regulatory applications, and commercializing product candidates. Our research, development, and commercialization efforts with respect to antibody candidates from our technology platforms are, in part, contingent upon the participation of institutional and corporate collaborators. For example, in February 2015 we began a broad collaboration with Incyte to pursue the discovery and development of CPMs. See “Risk Factors-Risks Related to our Business-We are dependent upon our collaboration with Incyte to further develop, manufacture and commercialize CPM antibodies against certain targets using our proprietary antibody discovery platforms. If we or Incyte fail to perform as expected, the potential for us to generate future revenues under the collaboration would be significantly reduced, the development and/or commercialization of these CPM antibodies may be terminated or substantially delayed, and our business would be severely harmed.” Furthermore, we have a collaboration arrangement with Recepta for CTLA-4 and PD-1, giving Recepta rights to certain South American countries and requiring us to agree upon development plans for these candidates. Disagreements or the failure of either party to perform satisfactorily could have an adverse impact on these programs.

In addition, substantially all product candidates containing QS-21 Stimulon depend on the success of our collaboration partners or licensees, and our relationships with these third parties. Such product candidates depend on our collaborators and licensees successfully enrolling patients and completing clinical trials, being committed to dedicating the resources necessary to advance these product candidates, obtaining regulatory approvals, and successfully manufacturing and commercializing product candidates.

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To date, the development of Prophage vaccine for the treatment of patients with glioma is dependent, in large part, on the efforts of the Alliance for Clinical Trials in Oncology, a NCI cooperative group, which is sponsoring a Phase 2 clinical trial of this product candidate in this indication. When our licensees or third party collaborators sponsor clinical trials using our product candidates, we cannot control the timing of enrollment, data readout, or quality of such trials or related activities. In addition, substantially all product candidates containing QS-21 Stimulon depend on the success of our collaboration partners or licensees, and our relationships with these third parties. Such product candidates depend on our collaborators and licensees successfully enrolling patients and completing clinical trials, being committed to dedicating the resources to advance these product candidates, obtaining regulatory approvals, and successfully manufacturing and commercializing product candidates.

Development activities for our collaboration programs may fail to produce marketable products due to unsuccessful results or abandonment of these programs, failure to enter into future collaborations or license agreements, or the inability to manufacture product supply requirements for our collaborators and licensees. Several of our agreements also require us to transfer important rights and regulatory compliance responsibilities to our collaborators and licensees. As a result of these collaboration agreements, we will not control the nature, timing, or cost of bringing these product candidates to market. Our collaborators and licensees could choose not to, or be unable to, devote resources to these arrangements or adhere to required timelines, or, under certain circumstances, may terminate these arrangements early. They may cease pursuing product candidates or elect to collaborate with different companies. In addition, these collaborators and licensees, outside of their arrangements with us, may develop technologies or products that are competitive with those that we are developing. From time to time, we may also become involved in disputes with our collaborators or licensees. Such disputes could result in the incurrence of significant expense, or the termination of collaborations. We may be unable to fulfill all of our obligations to our collaborators, which may result in the termination of collaborations. As a result of these factors, our strategic collaborations may not yield revenue. Furthermore, we may not be able to enter into new collaborations on favorable terms or at all. Failure to generate significant revenue from collaborations could increase our need to fund our operations through sales of debt or equity securities and would negatively affect our business prospects.

Our internal computer systems, or those of our third-party CROs, CMOs, licensees, collaborators or other contractors or consultants, may fail or suffer security breaches, which could result in a material disruption in our business and operations.

Despite the implementation of security measures, our internal computer systems and those of our current and future CROs, CMOs, licensees, collaborators and other contractors and consultants are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. While we are not aware of any such material system failure, accident or security breach to date, if such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our development programs and our business operations. For example, the loss of clinical trial data from completed, on-going or future clinical trials could result in delays in our regulatory approval efforts and significant costs to recover or reproduce the data. Likewise, we rely on third parties to manufacture our drug candidates and conduct clinical trials, and similar events relating to their computer systems could also have a material adverse effect on our business. To the extent that any disruption or security breach were to result in a loss of, or damage to, our data or applications, or inappropriate disclosure of confidential or proprietary information, we could incur liabilities and the further development and commercialization of our product candidates could be delayed.

We are highly reliant on our Chief Executive Officer, President of R&D and other members of our management team. In addition, we have limited internal resources and if we fail to recruit and/or retain the services of key employees and external consultants as needed, we may not be able to achieve our strategic and operational objectives.

Both Garo H. Armen, Ph.D., the Chairman of our Board of Directors and our Chief Executive Officer who co-founded the Company in 1994, and Dr. Robert Stein, our President of R&D who joined the Company in February 2014, are integral to building our company and developing our technology. If either Dr. Armen or Dr. Stein is unable or unwilling to continue his relationship with Agenus, our business may be adversely impacted.

Effective December 31, 2005, we entered into an employment agreement with Dr. Armen. Subject to the early termination of the agreement, the agreement had an original term of one year and is automatically extended thereafter for successive terms of one year each, unless either party provides notice to the other at least 90 days prior to the expiration of the original or any extension term. Effective June 30, 2015, we entered into an employment agreement with Dr. Stein. Subject to the early termination of the agreement, the agreement has an original term of one year and is automatically extended thereafter for successive terms of one year each, unless either party provides notice to the other at least 120 days prior to the expiration of the original or any extension term. Dr. Armen and Dr. Stein play important roles in our day-to-day activities. We do not carry key employee insurance policies for Dr. Armen, Dr. Stein or any other employee.

Our future growth success depends to a significant extent on the skills, experience and efforts of our executive officers and key members of our clinical and scientific staff. We face intense competition for qualified individuals from other pharmaceutical, biopharmaceutical and biotechnology companies, as well as academic and other research institutions. We may be unable to retain our

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current personnel or attract or assimilate other highly qualified management and clinical personnel in the future on acceptable terms. The loss of any or all of these individuals could harm our business and could impair our ability to support our collaboration with Incyte or to support our growth. If our management is unable to effectively manage our growth, our expenses may increase more than expected, our ability to generate revenue could be reduced and we may not be able to implement our business strategy.

We rely on a small staff of highly trained and experienced senior management and scientific, administrative and operations personnel and consultants to conduct our business in certain key areas of our organization. The competition for qualified personnel in the biotechnology field is intense, and if we are not able to continue to attract and retain qualified personnel and/or maintain positive relationships with our outside consultants, we may not be able to achieve our strategic and operational objectives.

Calamities, power shortages or power interruptions could disrupt our business and materially adversely affect our operations.

In December 2015, we acquired an antibody pilot plant manufacturing facility and leased additional office space in Berkeley, CA. This location is in an area of seismic activity near active earthquake faults. Any earthquake, terrorist attack, fire, power shortage or other calamity affecting our facilities or those of third parties upon whom we depend may disrupt our business and could have a material adverse effect on our business, results of operations, financial condition and prospects. If a natural disaster, power outage or other event occurred that prevented us from using all or a significant portion of our facilities, that damaged critical infrastructure (such as our manufacturing facility) or that otherwise disrupted operations, it may be difficult or, in certain cases, impossible for us to continue our manufacturing capabilities for a substantial period of time. The disaster recovery and business continuity plans we have in place currently are limited and are unlikely to prove adequate in the event of a serious disaster or similar event. We may incur substantial expenses and delays as a result of the limited nature of our disaster recovery and business continuity plans, which could have a material adverse effect on our business.

Risks Related to Regulation of the Biopharmaceutical Industry

The drug development and approval process is uncertain, time-consuming, and expensive.

Clinical development, including pre-clinical testing and the process of obtaining and maintaining regulatory approvals for new therapeutic products, is lengthy, expensive, and uncertain. For example, as of December 31, 2015, we had spent approximately 20 years and $473.5 million on our research and development program in heat shock proteins for cancer. The development and regulatory approval process also can vary substantially based on the type, complexity, and novelty of the product. We must provide regulatory authorities with manufacturing, product characterization, and pre-clinical and clinical data demonstrating that our product candidates are safe and effective before they can be approved for commercial sale. It may take us many years to complete our testing, and failure can occur at any stage of testing. Interim results of pre-clinical studies or clinical trials do not necessarily predict their final results, and acceptable results in early studies might not be seen in later studies. Any pre-clinical or clinical test may fail to produce results satisfactory to regulatory authorities for many reasons, including but not limited to insufficient product characterization, poor study structure conduct or statistical analysis planning, failure to enroll a sufficient number of patients or failure to prospectively identify the most appropriate patient eligibility criteria, and collectability of data. Pre-clinical and clinical data can be interpreted in different ways, which could delay, limit, or prevent regulatory approval. Negative or inconclusive results from a pre-clinical study or clinical trial, adverse medical events during a clinical trial, or safety issues resulting from products of the same class of drug could require a pre-clinical study or clinical trial to be repeated or cause a program to be terminated, even if other studies or trials relating to the program are successful. We or the FDA, other regulatory agencies, or an institutional review board may suspend or terminate human clinical trials at any time on various grounds.

The timing and success of a clinical trial is dependent on obtaining and maintaining sufficient cash resources, successful production of clinical trial material, enrolling sufficient patients in a timely manner, avoiding serious or significant adverse patient reactions, and demonstrating efficacy of the product candidate in order to support a favorable risk versus benefit profile, among other considerations. The timing and success of our clinical trials, in particular, are also dependent on clinical sites and regulatory authorities accepting each trial’s protocol, statistical analysis plan, product characterization tests, and clinical data. In addition, regulatory authorities may request additional information or data that is not readily available. Delays in our ability to respond to such requests would delay, and failure to adequately address concerns would prevent, our commercialization efforts. We have encountered in the past, and may encounter in the future, delays in initiating trial sites and enrolling patients into our clinical trials. Future enrollment delays will postpone the dates by which we expect to complete the impacted trials and the potential receipt of regulatory approval. There is no guarantee we will successfully initiate and/or complete our clinical trials.

Delays or difficulties in obtaining regulatory approvals or clearances for our product candidates may:

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Delays or failures in our receiving regulatory approval for our product candidates in a timely manner may result in us having to incur additional development expense and subject us to having to secure additional financing. As a result, we may not be able to commercialize them in the time frame anticipated, and our business will suffer.

Even if we receive marketing approval for our product candidates, such product approvals could be subject to restrictions or withdrawals. Regulatory requirements are subject to change. Further, even if we receive marketing approval, we may not receive sufficient coverage and adequate reimbursement for our products.

Regulatory authorities generally approve products for particular indications. If an approval is for a limited indication, this limitation reduces the size of the potential market for that product. Product approvals, once granted, are subject to continual review and periodic inspections by regulatory authorities. Our operations and practices are subject to regulation and scrutiny by the United States government, as well as governments of any other countries in which we do business or conduct activities. Later discovery of previously unknown problems or safety issues, and/or failure to comply with domestic or foreign laws, knowingly or unknowingly, can result in various adverse consequences, including, among other things, possible delay in approval or refusal to approve a product, warning letters, fines, injunctions, civil penalties, recalls or seizures of products, total or partial suspension of production, refusal of the government to renew marketing applications, complete withdrawal of a marketing application, corrective action requirements, and/or criminal prosecution, withdrawal of an approved product from the market, and/or exclusion from government health care programs. Such regulatory enforcement could have a direct and negative impact on the product for which approval is granted and could have a negative impact on the approval of any pending applications for marketing approval of new drugs or supplements to approved applications.

Because we operate in a highly regulated industry, regulatory authorities could take enforcement action against us in connection with our licensees’ or collaborators’, and/or our business and marketing activities for various reasons. For example, the FCPA prohibits U.S. companies and their representatives from offering, promising, authorizing, or making payments to foreign governmental officials for the purpose of obtaining or retaining business abroad.

From time to time, new legislation is passed into law that could significantly change the statutory provisions governing the approval, manufacturing, and marketing of products regulated by the FDA and other foreign health authorities. Additionally, regulations and guidance are often revised or reinterpreted by health agencies in ways that may significantly affect our business and our products. It is impossible to predict whether further legislative changes will be enacted, or whether regulations, guidance, or interpretations will change, and what the impact of such changes, if any, may be. For example, the Patient Protection and Affordable Care Act and the Health Care and Education Affordability Reconciliation Act of 2010, collectively, the ACA, enacted in March 2010, substantially changed the way healthcare is financed by both governmental and private insurers, and significantly impacted the pharmaceutical industry. With regard to pharmaceutical products, among other things, ACA is expected to expand, increase, and change the methodology regarding industry rebates for drugs covered under Medicaid programs; impose an annual, nondeductible fee on any entity that manufactures or imports specific branded prescription drugs and biologic agents, apportioned among those entities according to market share in certain government healthcare programs; expand eligibility criteria for Medicaid programs by, among other things, allowing states to offer Medicaid coverage to certain individuals with income at or below 133% of the federal poverty level; expand the entities eligible for discounts under the Public Health Service pharmaceutical pricing program; create a new Patient Centered Outcomes Research Institute to oversee, identify priorities in, and conduct comparative clinical effectiveness research, along with funding for such research; and make changes to the coverage requirements under the Medicare D program.

We expect both government and private health plans to continue to require healthcare providers, including healthcare providers that may one day purchase our products, to contain costs and demonstrate the value of the therapies they provide. Even if our product candidates are approved, the commercial success of our products will depend substantially on the extent to which they are covered by third-party payors, including government health authorities and private health insurers. In the United States, no uniform policy of coverage and reimbursement for products exists among third-party payors, and coverage and reimbursement for products can differ significantly from payor to payor. If coverage and reimbursement are not available, or reimbursement is available only to limited levels, we or our collaborators may not be able to successfully commercialize our product candidates.

New data from our research and development activities, and/or resource considerations could modify our strategy and result in the need to adjust our projections of timelines and costs of programs.

Because we are focused on novel technologies, our research and development activities, including our nonclinical studies and clinical trials, involve the ongoing discovery of new facts and the generation of new data, based on which we determine next steps for a relevant program. These developments can occur with varying frequency and constitute the basis on which our business is conducted. We make determinations on an ongoing basis as to which of these facts or data will influence timelines and costs of

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programs. We may not always be able to make such judgments accurately, which may increase the costs we incur attempting to commercialize our product candidates. We monitor the likelihood of success of our initiatives and we may need to discontinue funding of such activities if they do not prove to be commercially feasible, due to our limited resources.

We may need to successfully address a number of technological challenges in order to complete development of our product candidates. Moreover, these product candidates may not be effective in treating any disease or may prove to have undesirable or unintended side effects, toxicities, or other characteristics that may preclude our obtaining regulatory approvals or prevent or limit commercial use.

Risks Related to Intellectual Property Rights

If we are unable to obtain and enforce patent protection for our product candidates and related technology, our business could be materially harmed.

We rely upon a combination of patents, trade secret protection and confidentiality agreements to protect the intellectual property related to our product candidates and technology. Any disclosure to or misappropriation by third parties of our confidential proprietary information could enable competitors to duplicate or surpass our technological achievements, eroding our competitive position in the market. Our patent applications may not result in issued patents, and, even if issued, the patents may be challenged and invalidated. Moreover, our patents and patent applications may not be sufficiently broad to prevent others from practicing our technologies or developing competing products. We also face the risk that others may independently develop similar or alternative technologies or may design around our proprietary property.

Issued patents may be challenged, narrowed, invalidated or circumvented. In addition, court decisions may introduce uncertainty in the enforceability or scope of patents owned by biotechnology companies. The legal systems of certain countries do not favor the aggressive enforcement of patents, and the laws of foreign countries may not allow us to protect our inventions with patents to the same extent as the laws of the United States. Because patent applications in the United States and many foreign jurisdictions are typically not published until 18 months after filing, or in some cases not at all, and because publications of discoveries in scientific literature lag behind actual discoveries, we cannot be certain that we were the first to make the inventions claimed in our issued patents or pending patent applications, or that we were the first to file for protection of the inventions set forth in our patents or patent applications. As a result, we may not be able to obtain or maintain protection for certain inventions. Therefore, the enforceability and scope of our patents in the United States and in foreign countries cannot be predicted with certainty and, as a result, any patents that we own or license may not provide sufficient protection against competitors. We may not be able to obtain or maintain patent protection from our pending patent applications, from those we may file in the future, or from those we may license from third parties. Moreover, even if we are able to obtain patent protection, such patent protection may be of insufficient scope to achieve our business objectives.

Patent terms may be inadequate to protect our competitive position on our product candidates for an adequate amount of time. Patents have a limited lifespan. In the United States, the natural expiration of a patent is generally 20 years after its effective filing date. Various extensions may be available; however the life of a patent, and the protection it affords, is limited. Without patent protection for our product candidates, we may be open to competition from generic versions of our product candidates. Furthermore, the product development timeline for biotechnology products is lengthy and it is possible that our issued patents covering our product candidates in the United States and other jurisdictions may expire prior to commercial launch. For example, if we encounter delays in our development efforts, including our clinical trials, the period of time during which we could market our product candidates under patent protection could be reduced.

Our strategy depends on our ability to identify and seek patent protection for our discoveries. This process is expensive and time consuming, and we and our current or future licensors may not be able to file and prosecute all necessary or desirable patent applications at a reasonable cost or in a timely manner or in all jurisdictions where protection may be commercially advantageous. It is also possible that we or our current licensors, or any future licensors or licensees, may not identify patentable aspects of inventions made in the course of development and commercialization activities in time to obtain patent protection on them. Therefore, these and any of our patents and applications may not be prosecuted and enforced in a manner consistent with the best interests of our business. Defects of form in the preparation or filing of our patents or patent applications may exist, or may arise in the future, for example with respect to proper priority claims, inventorship, etc. If we or our current licensors, or any future licensors or licensees, fail to establish, maintain or protect such patents and other intellectual property rights, such rights may be reduced or eliminated. If our current licensors, or any future licensors or licensees, are not fully cooperative or disagree with us as to the prosecution, maintenance or enforcement of any patent rights, such patent rights could be compromised. If there are material defects in the form or preparation of our patents or patent applications, such patents or applications may be invalid and unenforceable. Despite our efforts to protect our proprietary rights, unauthorized parties may be able to obtain and use information that we regard as proprietary. The issuance of a patent does not ensure that it is valid or enforceable, so even if we obtain patents, they may not be valid or enforceable against third parties. In addition, the issuance of a patent does not give us the right to practice the patented invention. Third parties may have

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blocking patents that could prevent us from marketing our own patented product and practicing our own patented technology. Any of these outcomes could impair our ability to prevent competition from third parties, which may have an adverse impact on our business.

The patent landscape in the field of therapeutic antibody development, manufacture and commercialization is crowded. For example, we are aware of third party patents directed to methods for identifying and producing therapeutic antibodies. We are also aware of third party patents directed to antibodies to numerous targets for which we also seek to identify, develop, and commercialize antibodies, including without limitation CTLA-4, PD-1, GITR, OX40, TIM-3, LAG-3, and CEACAM1. For example, some patents claim antibodies based on competitive binding with existing antibodies, some claim antibodies based on specifying sequence or other structural information, and some claim various methods of discovery, production, or use of such antibodies.

These or other third party patents could impact our freedom to operate in relation to our technology platforms, as well as in relation to development and commercialization of antibodies identified by us as therapeutic candidates. As we discover and develop our candidate antibodies, we will continue to conduct analyses of these third party patents to determine whether we believe we might infringe them, and if so, whether they would be likely to be deemed valid and enforceable if challenged. If we determine that a license for a given patent or family of patents is necessary or desirable, there can be no guarantee that a license would be available on favorable terms, or at all. Inability to obtain a license on favorable terms, should such a license be determined to be necessary or desirable, could, without limitation, result in increased costs to design around the third party patents, delay product launch, or result in cancellation of the affected program or cessation of use of the affected technology.

Third parties may also seek to market biosimilar versions of any approved products. Alternatively, third parties may seek approval to market their own products similar to or otherwise competitive with our products. In these circumstances, we may need to defend and/or assert our patents, including by filing lawsuits alleging patent infringement. In any of these types of proceedings, a court or agency with jurisdiction may find our patents invalid and/or unenforceable. Even if we have valid and enforceable patents, these patents still may not provide protection against competing products or processes sufficient to achieve our business objectives.

We own, co-own or have exclusive rights to approximately 50 issued United States patents and approximately 120 issued foreign patents. We also own, co-own or have exclusive rights to approximately 50 pending United States patent applications and approximately 50 pending foreign patent applications. However, our patents may not protect us against our competitors. Our patent positions, and those of other biopharmaceutical, pharmaceutical and biotechnology companies, are generally uncertain and involve complex legal, scientific, and factual questions. The standards which the United States Patent and Trademark Office, or USPTO, uses to grant patents, and the standards which courts use to interpret patents, are not always applied predictably or uniformly and can change, particularly as new technologies develop. Consequently, the level of protection, if any, that will be provided by our patents if we attempt to enforce them, and they are challenged, is uncertain. In addition, the type and extent of patent claims that will be issued to us in the future is uncertain. Any patents that are issued may not contain claims that permit us to stop competitors from using similar technology.

Through our acquisitions of 4-AB, PhosImmune and certain assets of Celexion, we own, co-own, or have exclusive rights to a number of patents and patent applications directed to various methods and compositions, including methods for identifying therapeutic antibodies and product candidates arising out of such entities’ technology platforms. In particular, we own patents and patent applications relating to Retrocyte Display^TM technology platform, a high throughput antibody expression platform for the identification of fully-human and humanized monoclonal antibodies. This patent family is projected to expire between 2029 and 2031. Through our acquisition of PhosImmune, we own, co-own, or have exclusive rights to patents and patent applications directed to various methods and compositions, including a patent directed to methods for identifying phosphorylated proteins using mass spectrometry. This patent is projected to expire in 2023. We also own patents and patent applications relating to the SECANT^® platform, a platform used for the generation of novel monoclonal antibodies. This patent family is projected to expire between 2028 and 2029. In addition, as we advance our research and development efforts with our institutional and corporate collaborators, we intend to seek patent protection for newly identified therapeutic antibodies and product candidates. We can provide no assurance that any of our patents, including the patents that we acquired or in-licensed in connection with our acquisitions of 4-AB, PhosImmune and certain assets of Celexion, will have commercial value, or that any of our existing or future patent applications, including the patent applications that we acquired or in-licensed in connection with our acquisitions of 4-AB, PhosImmune and certain assets of Celexion, will result in the issuance of valid and enforceable patents.

Our issued patents covering Prophage vaccine and methods of use thereof, alone or in combination with other agents, expired or will expire at various dates between 2015 and 2024. In particular, our issued U.S. patents covering Prophage composition of matter expired in 2015. In addition, our issued patents covering QS-21 Stimulon composition of matter expired in 2008. We continue to explore means of extending the life cycle of our patent portfolio.

The patent position of biopharmaceutical, pharmaceutical or biotechnology companies, including ours, is generally uncertain and involves complex legal and factual considerations. The standards which the USPTO and its foreign counterparts use to grant patents are not always applied predictably or uniformly and can change. There is also no uniform, worldwide policy regarding the

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subject matter and scope of claims granted or allowable in biopharmaceutical, pharmaceutical or biotechnology patents. The laws of some foreign countries do not protect proprietary information to the same extent as the laws of the United States, and many companies have encountered significant problems and costs in protecting their proprietary information in these foreign countries. Outside the United States, patent protection must be sought in individual jurisdictions, further adding to the cost and uncertainty of obtaining adequate patent protection outside of the United States. Accordingly, we cannot predict whether additional patents protecting our technology will issue in the United States or in foreign jurisdictions, or whether any patents that do issue will have claims of adequate scope to provide competitive advantage. Moreover, we cannot predict whether third parties will be able to successfully obtain claims or the breadth of such claims. The allowance of broader claims may increase the incidence and cost of patent interference proceedings, opposition proceedings, post-grant review, inter partes review, and/or reexamination proceedings, the risk of infringement litigation, and the vulnerability of the claims to challenge. On the other hand, the allowance of narrower claims does not eliminate the potential for adversarial proceedings, and may fail to provide a competitive advantage. Our issued patents may not contain claims sufficiently broad to protect us against third parties with similar technologies or products, or provide us with any competitive advantage.

We may become involved in lawsuits to protect or enforce our patents, which could be expensive, time consuming and unsuccessful.

Third parties may infringe or misappropriate our intellectual property, including our existing patents, patents that may issue to us in the future, or the patents of our licensors to which we have a license. As a result, we may be required to file infringement claims to stop third-party infringement or unauthorized use. Further, we may not be able to prevent, alone or with our licensors, misappropriation of our intellectual property rights, particularly in countries where the laws may not protect those rights as fully as in the United States.

If we or one of our licensors were to initiate legal proceedings against a third party to enforce a patent covering our product candidates, the defendant could counterclaim that the patent covering our product candidates is invalid and/or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity and/or unenforceability are commonplace, and there are numerous grounds upon which a third party can assert invalidity or unenforceability of a patent.

In addition, within and outside of the United States, there has been a substantial amount of litigation and administrative proceedings, including interference and reexamination proceedings before the USPTO or oppositions and other comparable proceedings in various foreign jurisdictions, regarding patent and other intellectual property rights in the biopharmaceutical industry. Recently, the AIA introduced new procedures, including inter partes review and post grant review. These procedures may be used by competitors to challenge the scope and/or validity of our patents, including those that patents perceived by our competitors as blocking entry into the market for their products, and the outcome of such challenges.

Even after they have been issued, our patents and any patents which we license may be challenged, narrowed, invalidated or circumvented. If our patents are invalidated or otherwise limited or will expire prior to the commercialization of our product candidates, other companies may be better able to develop products that compete with ours, which could adversely affect our competitive business position, business prospects and financial condition.

The following are examples of litigation and other adversarial proceedings or disputes that we could become a party to involving our patents or patents licensed to us:

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These lawsuits and proceedings would be costly and could affect our results of operations and divert the attention of our managerial and scientific personnel. There is a risk that a court or administrative body could decide that our patents are invalid or not infringed by a third party’s activities, or that the scope of certain issued claims must be further limited. An adverse outcome in a litigation or proceeding involving our own patents could limit our ability to assert our patents against these or other competitors, affect our ability to receive royalties or other licensing consideration from our licensees, and may curtail or preclude our ability to exclude third parties from making, using and selling similar or competitive products. An adverse outcome may also put our pending patent applications at risk of not issuing, or issuing with limited and potentially inadequate scope to cover our product candidates. The outcome following legal assertions of invalidity and unenforceability is unpredictable. With respect to the validity question, for example, we cannot be certain that there is no invalidating prior art, of which we and the patent examiner were unaware during prosecution. Additionally, it is also possible that prior art of which we are aware, but which we do not believe affects the validity or enforceability of a claim, may, nonetheless, ultimately be found by a court of law or an administrative panel to affect the validity or enforceability of a claim, for example, if a priority claim is found to be improper. If a defendant were to prevail on a legal assertion of invalidity and/or unenforceability, we could lose at least part, and perhaps all, of the patent protection on our relevant product candidates. Such a loss of patent protection could have a material adverse impact on our business.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation or administrative proceedings, there is a risk that some of our confidential information could be compromised by disclosure. In addition, during the course of litigation or administrative proceedings, there could be public announcements of the results of hearings, motions or other interim proceedings or developments or public access to related documents. If investors perceive these results to be negative, the market price for our common stock could be significantly harmed. Any of these occurrences could adversely affect our competitive business position, business prospects, and financial condition.

Intellectual property rights do not necessarily address all potential threats to our competitive advantage. The degree of future protection for our proprietary rights is uncertain because legal means afford only limited protection and may not adequately protect our rights or permit us to gain or keep our competitive advantage. For example:

Our commercial success depends significantly on our ability to operate without infringing the patents and other proprietary rights of third parties.

Our success will depend in part on our ability to operate without infringing the proprietary rights of third parties. Other entities may have or obtain patents or proprietary rights that could limit our ability to make, use, sell, offer for sale or import our future approved products or impair our competitive position. In particular the patent landscape around the discovery, development, manufacture and commercial use of our pre-clinical CPM antibody programs and therapeutic antibodies is crowded.

Third parties may have or obtain valid and enforceable patents or proprietary rights that could block us from developing product candidates using our technology. Our failure to obtain a license to any technology that we require may materially harm our business, financial condition and results of operations. Moreover, our failure to maintain a license to any technology that we require may also materially harm our business, financial condition, and results of operations. Furthermore, we would be exposed to a threat of litigation.

In the biopharmaceutical industry, significant litigation and other proceedings regarding patents, patent applications, trademarks and other intellectual property rights have become commonplace. The types of situations in which we may become a party to such litigation or proceedings include:

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These lawsuits would be costly and could affect our results of operations and divert the attention of our management and scientific personnel. There is a risk that a court would decide that we or our collaborators are infringing the third party’s patents and would order us or our collaborators to stop the activities covered by the patents. In that event, we or our collaborators may not have a viable alternative to the technology protected by the patent and may need to halt work on the affected product candidate or cease commercialization of an approved product. In addition, there is a risk that a court will order us or our collaborators to pay the other party damages. An adverse outcome in any litigation or other proceeding could subject us to significant liabilities to third parties and require us to cease using the technology that is at issue or to license the technology from third parties. We may not be able to obtain any required licenses on commercially acceptable terms or at all. Any of these outcomes could have a material adverse effect on our business.

The biopharmaceutical industry has produced a significant number of patents, and it may not always be clear to industry participants, including us, which patents cover various types of products or methods of use. The coverage of patents is subject to interpretation by the courts, and the interpretation is not always uniform or predictable. If we are sued for patent infringement, we would need to demonstrate that our products or methods either do not infringe the patent claims of the relevant patent or that the patent claims are invalid, and we may not be able to do this. Proving invalidity is difficult. For example, in the United States, proving invalidity requires a showing of clear and convincing evidence to overcome the presumption of validity enjoyed by issued patents. Even if we are successful in these proceedings, we may incur substantial costs and divert management’s time and attention in pursuing these proceedings, which could have a material adverse effect on us. If we are unable to avoid infringing the patent rights of others, we may be required to seek a license, defend an infringement action or challenge the validity of the patents in court. Patent litigation is costly and time consuming. We may not have sufficient resources to bring these actions to a successful conclusion. In addition, if we do not obtain a license, develop or obtain non-infringing technology, fail to defend an infringement action successfully or have infringed patents declared invalid, we may incur substantial monetary damages, encounter significant delays in bringing our product candidates to market and be precluded from manufacturing or selling our product candidates.

The cost of any patent litigation or other proceeding, even if resolved in our favor, could be substantial. Some of our competitors may be able to sustain the cost of such litigation and proceedings more effectively than we can because of their substantially greater resources. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could have a material adverse effect on our ability to compete in the marketplace. Patent litigation and other proceedings may also absorb significant management time.  

If we fail to comply with our obligations under our intellectual property licenses with third parties, we could lose license rights that are important to our business.

We are currently party to various intellectual property license agreements. These license agreements impose, and we expect that future license agreements may impose, various diligence, milestone payment, royalty, insurance and other obligations on us. These licenses typically include an obligation to pay an upfront payment, yearly maintenance payments and royalties on sales. If we fail to comply with our obligations under the licenses, the licensors may have the right to terminate their respective license agreements, in which event we might not be able to market any product that is covered by the agreements. Termination of the license agreements or reduction or elimination of our licensed rights may result in our having to negotiate new or reinstated licenses with less favorable terms, which could adversely affect our competitive business position and harm our business.

If we are unable to protect the confidentiality of our proprietary information, the value of our technology and products could be adversely affected.

In addition to patent protection, we also rely on other proprietary rights, including protection of trade secrets, and other proprietary information. To maintain the confidentiality of trade secrets and proprietary information, we enter into confidentiality agreements with our employees, consultants, collaborators and others upon the commencement of their relationships with us. These agreements require that all confidential information developed by the individual or made known to the individual by us during the course of the individual’s relationship with us be kept confidential and not disclosed to third parties. Our agreements with employees and our personnel policies also provide that any inventions conceived by the individual in the course of rendering services to us shall be our exclusive property. However, we may not obtain these agreements in all circumstances, and individuals with whom we have these agreements may not comply with their terms. Thus, despite such agreement, such inventions may become assigned to third parties. In the event of unauthorized use or disclosure of our trade secrets or proprietary information, these agreements, even if obtained, may not provide meaningful protection, particularly for our trade secrets or other confidential information. To the extent that our employees, consultants or contractors use technology or know-how owned by third parties in their work for us, disputes may arise

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between us and those third parties as to the rights in related inventions. To the extent that an individual who is not obligated to assign rights in intellectual property to us is rightfully an inventor of intellectual property, we may need to obtain an assignment or a license to that intellectual property from that individual, or a third party or from that individual’s assignee. Such assignment or license may not be available on commercially reasonable terms or at all.

Adequate remedies may not exist in the event of unauthorized use or disclosure of our proprietary information. The disclosure of our trade secrets would impair our competitive position and may materially harm our business, financial condition and results of operations. Costly and time consuming litigation could be necessary to enforce and determine the scope of our proprietary rights, and failure to maintain trade secret protection could adversely affect our competitive business position. In addition, others may independently discover or develop our trade secrets and proprietary information, and the existence of our own trade secrets affords no protection against such independent discovery.

As is common in the biopharmaceutical industry, we employ individuals who were previously or concurrently employed at research institutions and/or other biopharmaceutical, biotechnology or pharmaceutical companies, including our competitors or potential competitors. We may be subject to claims that these employees, or we, have inadvertently or otherwise used or disclosed trade secrets or other proprietary information of their former employers, or that patents and applications we have filed to protect inventions of these employees, even those related to one or more of our product candidates, are rightfully owned by their former or concurrent employer. Litigation may be necessary to defend against these claims. Even if we are successful in defending against these claims, litigation could result in substantial costs and be a distraction to management.

Obtaining and maintaining our patent protection depends on compliance with various procedural, documentary, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements.

Periodic maintenance fees, renewal fees, annuity fees and various other governmental fees on patents and/or applications will be due to the USPTO and various foreign patent offices at various points over the lifetime of our patents and/or applications. We have systems in place to remind us to pay these fees, and we rely on our outside counsel or service providers to pay these fees when due. Additionally, the USPTO and various foreign patent offices require compliance with a number of procedural, documentary, fee payment and other similar provisions during the patent application process. We employ reputable law firms and other professionals to help us comply, and in many cases, an inadvertent lapse can be cured by payment of a late fee or by other means in accordance with rules applicable to the particular jurisdiction. However, there are situations in which noncompliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. If such an event were to occur, it could have a material adverse effect on our business. In addition, we are responsible for the payment of patent fees for patent rights that we have licensed from other parties.

If any licensor of these patents does not itself elect to make these payments, and we fail to do so, we may be liable to the licensor for any costs and consequences of any resulting loss of patent rights.

Changes in U.S. patent law could diminish the value of patents in general, thereby impairing our ability to protect our product candidates.

Obtaining and enforcing patents in the biopharmaceutical industry involves both technological and legal complexity, and therefore, is costly, time-consuming and inherently uncertain. In addition, the United States has recently enacted and is currently implementing wide-ranging patent reform legislation. Further, recent U.S. Supreme Court rulings have either narrowed the scope of patent protection available in certain circumstances or weakened the rights of patent owners in certain situations. In addition to increasing uncertainty with regard to our ability to obtain patents in the future, this combination of events has created uncertainty with respect to the value of patents, once obtained.

For our U.S. patent applications containing a claim not entitled to priority before March 16, 2013, there is a greater level of uncertainty in the patent law. In September 2011, the Leahy-Smith America Invents Act, or the American Invents Act, or AIA, was signed into law. The AIA includes a number of significant changes to U.S. patent law, including provisions that affect the way patent applications will be prosecuted and may also affect patent litigation. The USPTO is currently developing regulations and procedures to govern administration of the AIA, and many of the substantive changes to patent law associated with the AIA. It is not clear what other, if any, impact the AIA will have on the operation of our business. Moreover, the AIA and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have a material adverse effect on our business and financial condition.

An important change introduced by the AIA is that, as of March 16, 2013, the United States transitioned to a “first-to- file” system for deciding which party should be granted a patent when two or more patent applications are filed by different parties claiming the same invention. A third party that files a patent application in the USPTO after that date but before us could therefore be awarded a patent covering an invention of ours even if we had made the invention before it was made by the third party. This will

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require us to be cognizant going forward of the time from invention to filing of a patent application. Furthermore, our ability to obtain and maintain valid and enforceable patents depends on whether the differences between our technology and the prior art allow our technology to be patentable over the prior art. Since patent applications in the United States and most other countries are confidential for a period of time after filing, we cannot be certain that we were the first to either (i) file any patent application related to our product candidates or (ii) invent any of the inventions claimed in our patents or patent applications.

Among some of the other changes introduced by the AIA are changes that limit where a patentee may file a patent infringement suit and providing opportunities for third parties to challenge any issued patent in the USPTO. This applies to all of our U.S. patents, even those issued before March 16, 2013. Because of a lower evidentiary standard in USPTO proceedings compared to the evidentiary standard in United States federal court necessary to invalidate a patent claim, a third party could potentially provide evidence in a USPTO proceeding sufficient for the USPTO to hold a claim invalid even though the same evidence would be insufficient to invalidate the claim if first presented in a district court action. Accordingly, a third party may attempt to use the USPTO procedures to invalidate our patent claims that would not have been invalidated if first challenged by the third party as a defendant in a district court action.

We may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties.

We may have received confidential and proprietary information from third parties. In addition, we employ individuals who were previously employed at other biopharmaceutical, biotechnology or pharmaceutical companies. We may be subject to claims that we or our employees, consultants or independent contractors have inadvertently or otherwise improperly used or disclosed confidential information of these third parties or our employees’ former employers. Further, we may be subject to ownership disputes in the future arising, for example, from conflicting obligations of consultants or others who are involved in developing our product candidates. We may also be subject to claims that former employees, consultants, independent contractors, collaborators or other third parties have an ownership interest in our patents or other intellectual property. Litigation may be necessary to defend against these and other claims challenging our right to and use of confidential and proprietary information. If we fail in defending any such claims, in addition to paying monetary damages, we may lose our rights therein. Such an outcome could have a material adverse effect on our business. Even if we are successful in defending against these claims, litigation could result in substantial cost and be a distraction to our management and employees.

We may not be able to protect our intellectual property rights throughout the world.

Filing, prosecuting and defending patents on our product candidates in all countries throughout the world would be prohibitively expensive. The requirements for patentability may differ in certain countries, particularly developing countries. For example, China has a heightened requirement for patentability, and specifically requires a detailed description of medical uses of a claimed drug. In addition, the laws of some foreign countries do not protect intellectual property rights to the same extent as laws in the United States. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the United States. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own products and, further, may export otherwise infringing products to territories where we have patent protection, but enforcement on infringing activities is inadequate. These products may compete with our product candidates, and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents and other intellectual property protection, particularly those relating to biopharmaceuticals, which could make it difficult for us to stop the infringement of our patents or marketing of competing products in violation of our proprietary rights generally. Proceedings to enforce our patent rights in foreign jurisdictions could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly and our patent applications at risk of not issuing, and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate and the damages or other remedies awarded, if any, may not be commercially meaningful. In addition, certain countries in Europe and certain developing countries, including India and China, have compulsory licensing laws under which a patent owner may be compelled to grant licenses to third parties. In those countries, we may have limited remedies if our patents are infringed or if we are compelled to grant a license to our patents to a third party, which could materially diminish the value of those patents. This could limit our potential revenue opportunities. Accordingly, our efforts to enforce our intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we own or license. Finally, our ability to protect and enforce our intellectual property rights may be adversely affected by unforeseen changes in foreign intellectual property laws.

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Risks Related to Litigation

We may face litigation or regulatory investigations that could result in substantial damages and may divert management’s time and attention from our business.

From time to time we may become a party to legal proceedings, claims and investigations that arise in the ordinary course of business such as, but not limited to, patent, employment, commercial and environmental matters. While we currently believe that the ultimate outcome of any of these proceedings will not have a material adverse effect on our financial position, results of operations, or liquidity, litigation is subject to inherent uncertainty. Furthermore, litigation consumes both cash and management attention.

We maintain property and general commercial insurance coverage as well as errors and omissions and directors and officers insurance policies. This insurance coverage may not be sufficient to cover us for future claims.

If we or our employees fail to comply with laws or regulations, it could adversely impact our reputation, business and stock price.

We are exposed to the risk of employee fraud or other misconduct. Misconduct by employees could include intentional and/or negligent failures to comply with FDA regulations, to provide accurate information to the FDA, to comply with manufacturing standards we have established, to comply with federal and state health care fraud and abuse, transparency, and/or data privacy and security laws and regulations, to report financial information or data accurately or to disclose unauthorized activities to us. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, kickbacks, self-dealing and other abusive practices; to promote transparency; and to protect the privacy and security of patient data. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements.

While we have adopted a corporate compliance program, we may not be able to protect against all potential issues of noncompliance. Efforts to ensure that our business complies with all applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices may not comply with current or future statutes, regulations, or case law involving applicable laws and regulations.

Employee misconduct could also involve the improper use or disclosure of information obtained in the course of clinical trials, which could result in regulatory sanctions and serious harm to our reputation. In addition, during the course of our operations, our directors, executives and employees may have access to material, nonpublic information regarding our business, our results of operations or potential transactions we are considering. We may not be able to prevent a director, executive or employee from trading in our common stock on the basis of, or while having access to, material, nonpublic information. If a director, executive or employee was to be investigated, or an action was to be brought against a director, executive or employee for insider trading, it could have a negative impact on our reputation and our stock price. Such a claim, with or without merit, could also result in substantial expenditures of time and money, and divert attention of our management team.

Product liability and other claims against us may reduce demand for our products and/or result in substantial damages.

We face an inherent risk of product liability exposure related to testing our product candidates in human clinical trials and manufacturing antibodies in our Berkeley, CA facility and may face even greater risks if we ever sell products commercially. An individual may bring a product liability claim against us if one of our product candidates causes, or merely appears to have caused, an injury. Product liability claims may result in:

We manufacture the Prophage vaccines from a patient’s cancer cells, and medical professionals must inject the vaccines into the same patient from which they were manufactured. A patient may sue us if a hospital, a shipping company, or we fail to receive the removed cancer tissue or deliver that patient’s vaccine. We anticipate that the logistics of shipping will become more complex if the number of patients we treat increases and that shipments of tumor and/or vaccines may be lost, delayed, or damaged. Additionally, complexities unique to the logistics of commercial products may delay shipments and limit our ability to move commercial product in an efficient manner without incident. We do not have any other insurance that covers loss of or damage to the Prophage vaccines or

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tumor material, and we do not know whether such insurance will be available to us at a reasonable price or at all. We have limited product liability coverage for use of our product candidates. Our product liability policy provides $10.0 million aggregate coverage and $10.0 million per occurrence coverage. This limited insurance coverage may be insufficient to fully cover us for future claims.

We are also subject to laws generally applicable to businesses, including but not limited to, federal, state and local wage and hour, employee classification, mandatory healthcare benefits, unlawful workplace discrimination and whistle-blowing. Any actual or alleged failure to comply with any regulation applicable to our business or any whistle-blowing claim, even if without merit, could result in costly litigation, regulatory action or otherwise harm our business, results of operations, financial condition, cash flow and future prospects.

If we do not comply with environmental laws and regulations, we may incur significant costs and potential disruption to our business.

We use or may use hazardous, infectious, and radioactive materials, and recombinant DNA in our operations, which have the potential of being harmful to human health and safety or the environment. We store these hazardous (flammable, corrosive, toxic), infectious, and radioactive materials, and various wastes resulting from their use, at our facilities pending use and ultimate disposal. We are subject to a variety of federal, state, and local laws and regulations governing use, generation, storage, handling, and disposal of these materials. We may incur significant costs complying with both current and future environmental health and safety laws and regulations. In particular, we are subject to regulation by the Occupational Safety and Health Administration, the Environmental Protection Agency, the Drug Enforcement Agency, the Department of Transportation, the Centers for Disease Control and Prevention, the National Institutes of Health, the International Air Transportation Association, and various state and local agencies. At any time, one or more of the aforementioned agencies could adopt regulations that may affect our operations. We are also subject to regulation under the Toxic Substances Control Act and the Resource Conservation Development programs.

Although we believe that our current procedures and programs for handling, storage, and disposal of these materials comply with federal, state, and local laws and regulations, we cannot eliminate the risk of accidents involving contamination from these materials. Although we have a workers’ compensation liability policy, we could be held liable for resulting damages in the event of an accident or accidental release, and such damages could be substantially in excess of any available insurance coverage and could substantially disrupt our business.

Risks Related to our Common Stock

Provisions in our organizational documents could prevent or frustrate attempts by stockholders to replace our current management.

Our certificate of incorporation and bylaws contain provisions that could make it more difficult for a third party to acquire us without the consent of our Board of Directors. Our certificate of incorporation provides for a staggered board and removal of directors only for cause. Accordingly, stockholders may elect only a minority of our Board at any annual meeting, which may have the effect of delaying or preventing changes in management. In addition, under our certificate of incorporation, our Board of Directors may issue additional shares of preferred stock and determine the terms of those shares of stock without any further action by our stockholders. Our issuance of additional preferred stock could make it more difficult for a third party to acquire a majority of our outstanding voting stock and thereby effect a change in the composition of our Board of Directors. Our certificate of incorporation also provides that our stockholders may not take action by written consent. Our bylaws require advance notice of stockholder proposals and director nominations and permit only our president or a majority of the Board of Directors to call a special stockholder meeting. These provisions may have the effect of preventing or hindering attempts by our stockholders to replace our current management. In addition, Delaware law prohibits a corporation from engaging in a business combination with any holder of 15% or more of its capital stock until the holder has held the stock for three years unless, among other possibilities, the board of directors approves the transaction. Our Board of Directors may use this provision to prevent changes in our management. Also, under applicable Delaware law, our Board of Directors may adopt additional anti-takeover measures in the future.

The first right to negotiate provision contained in our agreement with GSK could hinder or delay a change of control of our company or the sale of certain of our assets.

We have entered into a First Right to Negotiate and Amendment Agreement with GSK that affords GSK, one of our licensees, a first right to negotiate with us in the event we determine to initiate a process to effect a change of control of our company with, or to sell certain of our assets to, an unaffiliated third party or in the event that a third party commences an unsolicited tender offer seeking a change of control of our company. In such event, we must provide GSK a period of time to determine whether it wishes to negotiate the terms of such a transaction with us. If GSK affirmatively so elects, we are required to negotiate with GSK in good faith towards effecting a transaction of that nature for a specified period. During the negotiation period, we are obligated not to enter into a definitive agreement with a third party that would preclude us from negotiating and/or executing a definitive agreement with GSK. If

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GSK determines not to negotiate with us or we are unable to come to an agreement with GSK during this period, we may enter into the specified change of control or sale transaction within the following 12 months, provided that such a transaction is not on terms in the aggregate that are materially less favorable to us and our stockholders (as determined by our Board of Directors, in its reasonable discretion) than terms last offered to us by GSK in a binding written proposal during the negotiation period. The first right to negotiate terminates on March 2, 2017. Although GSK’s first right to negotiate does not compel us to enter into a transaction with GSK nor prevent us from negotiating with or entering into a transaction with a third party, the first right to negotiate could inhibit a third party from engaging in discussions with us concerning such a transaction or delay our ability to effect such a transaction with a third party.

Our stock has historically had low trading volume, and its public trading price has been volatile.

For the period from our initial public offering on February 4, 2000 to December 31, 2015, and for the year ended December 31, 2015, the closing price of our common stock has fluctuated between $1.80 (or $0.30 pre-reverse stock split) and $315.78 (or $52.63 pre-reverse stock split) per share and $3.88 and $9.78 per share, respectively. The average daily trading volume for the year ended December 31, 2015 was approximately 1,652,962 shares, while the average daily trading volume for the year ended December 31, 2014 was approximately 728,000. The market may experience significant price and volume fluctuations that are often unrelated to the operating performance of individual companies. In addition to general market volatility, many factors may have a significant adverse effect on the market price of our stock, including:

In the past, securities class action litigation has often been brought against a company following a significant decline in the market price of its securities. This risk is especially relevant for us because many biopharmaceutical, biotechnology and pharmaceutical companies experience significant stock price volatility.

The trading market for our common stock will depend in part on the research and reports that securities or industry analysts publish about us or our business. If one or more of the analysts who covers us downgrades our stock, or publishes inaccurate or unfavorable research about our business, our stock price would likely decline. If one or more of these analysts ceases coverage of us or fails to publish reports on us regularly, demand for our stock could decrease, which could cause our stock price and trading volume to decline.

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The sale of a significant number of shares could cause the market price of our stock to decline.

The sale by us or the resale by stockholders of a significant number of shares of our common stock could cause the market price of our common stock to decline. As of December 31, 2015, we had 86,390,697 shares of common stock outstanding. All of these shares are eligible for sale on NASDAQ, although certain of the shares are subject to sales volume and other limitations. We have filed registration statements to permit the sale of approximately 16,200,000 shares of common stock under our equity incentive plans, to permit the sale of 1,500,000 shares of common stock under our 2015 Inducement Equity Plan, and to permit the sale of 150,000 shares of common stock under an inducement grant. We have also filed registration statements to permit the sale of approximately 167,000 shares of common stock under our employee stock purchase plan, to permit the sale of 325,000 shares of common stock under our Directors’ Deferred Compensation Plan, to permit the sale of approximately 19,943,489 shares of common stock pursuant to various private placement agreements (including 1,400,000 shares of common stock issuable upon the exercise of certain warrants that we issued in February 2015) and to permit the sale of approximately 10,000,000 shares of our common stock pursuant to our At Market Issuance Sales Agreement. As of December 31, 2015, an aggregate of approximately 25 million of these shares remained available for sale. In connection with our acquisition of 4-AB in February 2014, we are obligated to make contingent milestone payments to the former shareholders of 4-AB, payable in cash or shares of our common stock at our option, as follows (i) $10.0 million upon our market capitalization exceeding $750.0 million for 30 consecutive trading days prior to the earliest of (a) the tenth anniversary of the Closing Date (b) the sale of 4-AB or (c) the sale of Agenus and (ii) $10.0 million upon our market capitalization exceeding $1.0 billion for 30 consecutive trading days prior to the earliest of (a) the tenth anniversary of the Closing Date, (b) the sale of 4-AB or (c) the sale of Agenus. In addition, as additional consideration for assets that we purchased from Celexion, we agreed to pay to Celexion $4.0 million on each of the 12-month and 24-month anniversaries of the Closing Date payable at our discretion in cash, shares of our common stock, or any combination thereof. In connection with our acquisition of PhosImmune in December 2015, we issued 1,631,521 shares of our common stock to the shareholders of PhosImmune and other third parties having a fair market value of approximately $7.4 million at closing. In addition, we may be obligated in the future to pay certain contingent milestones payments, payable at our election in cash or shares of our common stock of up to $35.0 million in the aggregate. We are also obligated to file registration statements covering any additional shares that may be issued to Celexion, XOMA or the former shareholders of PhosImmune in the future pursuant to the terms of our agreements with Celexion, XOMA and PhosImmune, respectively. The market price of our common stock may decrease based on the expectation of such sales. The market price of our common stock may decrease based on the expectation of such sales.

As of December 31, 2015, warrants to purchase approximately 4,351,450 shares of our common stock with a weighted average exercise price per share of $9.01 were outstanding.

As of December 31, 2015, options to purchase 8,345,835 shares of our common stock with a weighted average exercise price per share of $4.77 were outstanding. These options are subject to vesting that occurs over a period of up to four years following the date of grant. As of December 31, 2015 we had 7,649,324 vested options and 1,730,604 nonvested shares outstanding.

As of December 31, 2015, our outstanding shares of Series A-1 Convertible Preferred Stock were convertible into 333,333 shares of our common stock.

We may issue additional common stock, preferred stock, restricted stock units, or securities convertible into or exchangeable for our common stock. Furthermore, substantially all shares of common stock for which our outstanding stock options or warrants are exercisable are, once they have been purchased, eligible for immediate sale in the public market. The issuance of additional common stock, preferred stock, restricted stock units, or securities convertible into or exchangeable for our common stock or the exercise of stock options or warrants would dilute existing investors and could adversely affect the price of our securities. In addition, such securities may have rights senior to the rights of securities held by existing investors.

We do not intend to pay dividends on our common stock and, consequently your ability to obtain a return on your investment will depend on appreciation in the price of our common stock.

We have never declared or paid any cash dividend on our common stock and do not intend to do so in the foreseeable future. We currently anticipate that we will retain future earnings for the development, operation and expansion of our business. Therefore, the success of an investment in shares of our common stock will depend upon any future appreciation in their value. There is no guarantee that shares of our common stock will appreciate in value or maintain their current value.

Failure to maintain effective internal controls in accordance with Section 404 of the Sarbanes-Oxley Act of 2002 and to comply with changing regulation of corporate governance and public disclosure could have a material adverse effect on our operating results and the price of our common stock.

The Sarbanes-Oxley Act of 2002 and rules adopted by the SEC and NASDAQ have resulted in significant costs to us. In particular, our efforts to comply with Section 404 of the Sarbanes-Oxley Act of 2002 and related regulations regarding the required

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assessment of our internal control over financial reporting, and our independent registered public accounting firm’s audit of internal control over financial reporting, have required commitments of significant management time. We expect these commitments to continue.

Our internal control over financial reporting (as defined in Rules 13a-15 of the Exchange Act) is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of our consolidated financial statements for external purposes in accordance with U.S. GAAP. Because of its inherent limitations, internal control over financial reporting may not prevent or detect all deficiencies or weaknesses in our financial reporting. While our management has concluded that there were no material weaknesses in our internal control over financial reporting as of December 31, 2015, our procedures are subject to the risk that our controls may become inadequate because of changes in conditions or as a result of a deterioration in compliance with such procedures. No assurance is given that our procedures and processes for detecting weaknesses in our internal control over financial reporting will be effective.

Changing laws, regulations and standards relating to corporate governance and public disclosure, are creating uncertainty for companies. Laws, regulations and standards are subject to varying interpretations in some cases due to their lack of specificity, and as a result, their application in practice may evolve over time as new guidance is provided, which could result in continuing uncertainty regarding compliance matters and higher costs caused by ongoing revisions to disclosure and governance practices. If we fail to comply with these laws, regulations and standards, our reputation may be harmed and we might be subject to sanctions or investigation by regulatory authorities, such as the SEC. Any such action could adversely affect our operating results and the market price of our common stock.

None.

We lease our manufacturing, research and development, and corporate offices in Lexington, Massachusetts occupying approximately 82,000 square feet. This lease agreement terminates in August 2023 with an option to renew for one additional ten-year period. We have sublet portions of this facility under two subleases that expire in July 2016 and December 2017, respectively.

During December 2012 we entered into a commercial lease for approximately 5,600 square feet of office space in New York, New York for use as corporate offices that terminates in May 2020.

We also have research and office facilities in Jena, Germany and Basel, Switzerland whose lease expire in June 2018 and June 2016, respectively.

In December 2015, we entered into a commercial lease in Berkeley, California for approximately 10,900 square feet to be used for corporate offices which expires in December 2020.  We additionally executed two commercial sublease agreements in Berkeley, California for approximately 4,300 square feet and 8,200 square feet to be used for manufacturing, warehouse and corporate offices; both subleases expire in December 2016.  We additionally entered into a sublease in Berkeley, California for parking that expires in May 2020.

In December 2015, we also entered in a commercial lease agreement for approximately 15,300 square feet for laboratory and office space in Cambridge, United Kingdom for research and development that expires in December 2025.

In December 2015, we acquired and now own a manufacturing facility with approximately 24,000 square feet in Berkeley, California to be used in the production and manufacture of product candidates.

We believe substantially all of our property and equipment is in good condition and that we have sufficient capacity to meet our current operational needs. We do not anticipate experiencing significant difficulty in retaining occupancy of any of our manufacturing or office facilities and will do so through lease renewals prior to expiration or through replacing them with equivalent facilities.

We are not party to any material legal proceedings.

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Not applicable.

Executive Officers of the Registrant

Set forth below is certain information regarding our current executive officers, including their age, as of March 1, 2016:

Garo H. Armen, PhD—Garo Armen has been Chairman and CEO since the Company's founding in 1994. From mid-2002 through 2004, he was Chairman of the Board of Directors for the biopharmaceutical company Elan Corporation, plc, which he helped restructure.  Dr. Armen is also the founder and Chairman of the Children of Armenia Fund, a philanthropic organization established in 2000 that is dedicated to the positive development of the children and youth of rural Armenia.  He holds a PhD degree in physical organic chemistry from the City University of New York.

C. Evan Ballantyne—C. Evan Ballantyne joined the Company as Chief Financial Officer in June 2015. Prior to Agenus, Mr. Ballantyne served as Chief Financial Officer for Synthetic Biologics (NYSE: SYN) from February 2012 until May 2015. From 2006 until its acquisition in April 2011, Mr. Ballantyne served as Executive Vice President and Chief Financial Officer of Clinical Data (NASDAQ: CLDA), Inc., a publicly-traded biopharmaceutical company which was acquired by Forest Laboratories, Inc. for $1.3 billion. While at Clinical Data, he was instrumental in leading corporate financings totaling approximately $220.0 million as well as a number of acquisition and divestitures totaling $116.0 million. Mr. Ballantyne has also served as Chief Financial Officer of a number of private medical technology companies, including Avedro and ZymeQuest. Earlier in his career, he served as Vice President and Chief Operating Officer for ACNielsen Europe Middle East & Africa (NYSE: ART) and also held the position of Chief Financial Officer. There, Mr. Ballantyne was responsible for all aspects of operations, strategic planning and finance in more than 45 countries for a corporation with over 9,700 employees. Mr. Ballantyne also served as Director of Finance for IMS Health (NYSE: IMS). He began his career at the Dun & Bradstreet Corporation where he held several senior financial positions. Mr. Ballantyne earned a BA from the University of Western Ontario, and took a post-graduate degree in Business Administration with Honors from the University of Windsor.

Christine M. Klaskin—Christine M. Klaskin has been Vice President, Finance since October 2006. Since joining Agenus Inc. in 1996 as finance manager, Ms. Klaskin has held various positions within the finance department and has been involved in all equity and debt offerings of the Company including its IPO. Ms. Klaskin is currently a member of the board of directors of American DG Energy Inc. Prior to joining Agenus, Ms. Klaskin was employed by Arthur Andersen as an audit manager. Ms. Klaskin received her Bachelor of Accountancy from The George Washington University.

Ozer Baysal —Ozer Baysal has been Chief Business Officer since January 2013.  His principal role is to lead Agenus' efforts in establishing commercial capability and accelerating Agenus' transition to becoming a fully integrated biopharmaceutical company. Prior to joining Agenus Mr. Baysal spent more than 30 years with Pfizer in a broad number of functional and geographic areas, most recently serving as President of Europe, Emerging Markets Region. While at Pfizer, he held key leadership positions in Marketing, Sales, and Manufacturing, and was actively involved with numerous licensing and M&A activities. Mr. Baysal holds a bachelor's degree from Bosphorus University in Industrial Engineering and has completed the Programs for Leadership and Management Development at Harvard Business School.

Robert Stein, MD, PhD—Bob Stein has been President, Research and Development since September 2015.  Dr. Stein joined the Company as Chief Scientific Officer in February 2014.  Dr. Stein leads our Research, Preclinical Development and Translational Medicine functions and leads our global research and development efforts. Dr. Stein brings over 30 years of experience and accomplishments in the pharmaceutical and biotech industry to the Agenus leadership team. Over the course of his career Dr. Stein has played a pivotal role in bringing eight drugs to the market including Sustiva^®, Fablyn^®, Viviant^®, PanRetin^®, TargRetin^®, Promacta^®, & Eliquis^®. Prior to joining Agenus he held a number of senior management positions including Chief Scientific Officer & Senior Vice President of Research for Ligand Pharmaceuticals, Executive Vice President of Research & Preclinical Development for Dupont Merck, President and Chief Scientific Officer for Incyte Pharmaceuticals, President of Roche Palo Alto and CEO of KineMed. Dr. Stein spent the early part of his career at Merck, Sharp and Dohme Research Laboratories. He holds an MD and a PhD in

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Physiology & Pharmacology from Duke University.  Dr. Stein filed a personal voluntary bankruptcy petition under Chapter 7 in August of 2012 and the bankruptcy was discharged in May 2013.

Karen H. Valentine—Karen Higgins Valentine has been Chief Legal Officer and General Counsel since September 2015.  From January 2008 to September 2015, Ms. Valentine was Vice President and General Counsel and also has served as Secretary since 2007 and Chief Compliance Officer of the Company since 2008. Prior to joining Agenus Inc. in 2004, Ms. Valentine was an associate in the biotechnology practice of Palmer & Dodge LLP (now Locke Lorde). Ms. Valentine is currently a member of the board of directors of the Northeast Chapter of the Association of Corporate Counsel.  Ms. Valentine graduated cum laude with a bachelor’s degree in neuroscience from Colgate University, and received her law degree, magna cum laude, from Boston University School of Law.

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PART II

Our common stock is currently listed on The Nasdaq Capital Market under the symbol “AGEN.”

The following table sets forth, for the periods indicated, the high and low sale prices per share of our common stock.

As of January 7, 2016, there were approximately 826 holders of record and approximately 26,174 beneficial holders of our common stock.

We have never paid cash dividends on our common stock, and we do not anticipate paying any cash dividends in the foreseeable future. We currently intend to retain future earnings, if any, for the future operation and expansion of our business. Any future payment of dividends on our common stock will be at the discretion of our Board of Directors and will depend upon, among other things, our earnings, financial condition, capital requirements, level of indebtedness, and other factors that our Board of Directors deem relevant.

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Stock Performance

The following graph shows the cumulative total stockholder return on our common stock over the period spanning December 31, 2010 to December 31, 2015, as compared with that of the Nasdaq Stock Market (U.S. Companies) Index and the Nasdaq Biotechnology Index, based on an initial investment of $100 in each on December 31, 2010. Total stockholder return is measured by dividing share price change plus dividends, if any, for each period by the share price at the beginning of the respective period, and assumes reinvestment of dividends.

This stock performance graph shall not be deemed “filed” with the SEC or subject to Section 18 of the Exchange Act, nor shall it be deemed incorporated by reference in any of our filings under the Securities Act of 1933, as amended (the “Securities Act”).

COMPARISON OF CUMULATIVE TOTAL RETURN OF AGENUS INC.,

NASDAQ STOCK MARKET (U.S. COMPANIES) INDEX

AND NASDAQ BIOTECHNOLOGY INDEX

We have derived the condensed consolidated balance sheet data set forth below as of December 31, 2015 and 2014, and the condensed consolidated statement of operations data for each of the years in the three-year period ended December 31, 2015, from our audited consolidated financial statements included elsewhere in this Annual Report on Form 10-K.

You should read the selected condensed consolidated financial data in conjunction with “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” our consolidated financial statements, and the notes to our consolidated financial statements included elsewhere in this Annual Report on Form 10-K.

Changes in cash, cash equivalents, and short-term investments, total current assets, total assets, total current liabilities, long-term debt and stockholders’ equity  (deficit) in the periods presented below include the effects of the receipt of net proceeds from our debt offerings, equity offerings, the exercise of stock options, and employee stock purchases that totaled approximately $202.4 million, $57.0 million, $36.6 million, $10.5 million, and $8.1 million in the years ended December 31, 2015, 2014, 2013, 2012, and 2011, respectively.

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Overview

We are an immuno-oncology company focused on the discovery and development of revolutionary new treatments that engage the body’s immune system to benefit patients suffering from cancer. By combining multiple powerful platforms, we have established a highly integrated approach to target identification and validation, and for the discovery, development and manufacturing of monoclonal antibodies that modulate targets of interest. Our broad portfolio of novel checkpoint modulator and other immuno-modulatory monoclonal antibodies, vaccines and adjuvants, work in combination to provide the opportunity to create best-in-class therapeutic regimens. Our heat shock protein-based vaccine, Prophage™, has successfully completed Phase 2 studies in newly-diagnosed glioblastoma.

We are developing a comprehensive immuno-oncology portfolio driven by the following platforms and programs, which we intend to utilize individually and in combination:

We assess development, commercialization and partnering strategies for each of our product candidates periodically based on several factors, including pre-clinical and clinical trial results, competitive positioning and funding requirements and resources. We are currently collaborating with companies such as Incyte Corporation, Merck Sharpe & Dohme and Recepta Biopharma SA. Through these alliances, as well as our own internal programs, we currently have over a dozen antibody programs, including our anti-CTLA-4 (partnered with Recepta for certain South America territories) and anti-GITR (partnered with Incyte) antibody programs that each received FDA clearance to commence clinical trials in January 2016. We anticipate commencing these trials in the first half of 2016.

We are also advancing a series of HSP peptide-based vaccines to treat cancer. In July 2014, we reported positive results from a Phase 2 clinical trial with our Prophage vaccine, which showed that patients with newly-diagnosed GBM, or ndGBM, who were treated with a combination of our Prophage vaccine and standard of care showed substantial improvement both in progression-free survival and median overall survival, each as compared to historical control data. We plan to advance our Prophage vaccine into a randomized, well-controlled clinical trial for ndGBM in the second half of 2016. We also reported positive results in June 2014 from a Phase 2 clinical trial with our synthetic HerpV vaccine candidate for genital herpes. Although we determined not to move forward with this product candidate in herpes, based on our findings we launched our AutoSynVax synthetic cancer vaccine program in 2015, and we plan to initiate our first clinical trial for this program in the second half of 2016.

Our QS-21 Stimulon adjuvant is partnered with GlaxoSmithKline, or GSK, and is a key component in multiple GSK vaccine programs that target prophylactic or therapeutic impact in a variety of infectious diseases and cancer. These programs are in various stages, with the most advanced being GSK’s shingles and malaria programs, which GSK announced positive Phase 3 results for in December 2014 and October 2013, respectively. In September 2015, we monetized a portion of the future royalties we are contractually entitled to receive from GSK from sales of its shingles and malaria vaccines through a Note Purchase Agreement and received net proceeds of approximately $78.2 million.

Our business activities include product research and development, intellectual property prosecution, manufacturing, regulatory and clinical affairs, corporate finance and development activities, and support of our collaborations. Our product candidates require clinical trials and approvals from regulatory agencies, as well as acceptance in the marketplace. Part of our strategy is to develop and commercialize some of our product candidates by continuing our existing arrangements with academic and corporate collaborators and licensees and by entering into new collaborations.

Our common stock is currently listed on The Nasdaq Capital Market under the symbol “AGEN.”

Our research and development expenses for the years ended December 31, 2015, 2014, and 2013, were $70.4 million, $22.3 million, and $13.0 million, respectively. We have incurred significant losses since our inception. As of December 31, 2015, we had an accumulated deficit of $779.2 million.

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To date, we have financed our operations primarily through the sale of equity and debt securities. We believe that, based on our current plans and activities, our working capital resources at December 31, 2015 will be sufficient to satisfy our liquidity requirements through the first half of 2017. We may attempt to raise additional funds by: (1) pursuing collaboration, out-licensing and/or partnering opportunities for our portfolio programs and product candidates with one or more third parties, (2) renegotiating third party agreements, (3) selling assets, (4) securing additional debt financing and/or (5) selling equity securities. Satisfying long-term liquidity needs may require the successful commercialization and/or substantial out-licensing or partnering arrangements for our antibody discovery platforms, CPM antibody programs, HSP-based vaccines, and vaccines containing QS-21 Stimulon under development by our licensees. Our long-term success will also be dependent on the successful identification, development and commercialization of potential other product candidates, each of which will require additional capital with no certainty of timing or probability of success. If we incur operating losses for longer than we expect and/or we are unable to raise additional capital, we may become insolvent and be unable to continue our operations.

Historical Results of Operations

Year Ended December 31, 2015 Compared to the Year Ended December 31, 2014

Revenue: We generated revenue of $24.8 million and $7.0 million during the years ended December 31, 2015 and 2014, respectively. Revenue primarily includes fees earned under our license agreements, including approximately $14.4 million for the year ended December 31, 2015, related to reimbursement of development costs under our Collaboration Agreement with Incyte. In 2014, revenues included license fees earned and grant revenue.  The increase in revenue for the year ended December 31, 2015 is primarily attributable to the amortization of deferred revenue and reimbursement of development costs under our Collaboration Agreement with Incyte. During the years ended December 31, 2015 and 2014, we recorded revenue of $9.3 million and $3.5 million, respectively, from the amortization of deferred revenue.

Research and Development: Research and development expenses include the costs associated with our internal research and development activities, including compensation and benefits, occupancy costs, clinical manufacturing costs, costs of consultants, and administrative costs. Research and development expense increased 215% to $70.4 million for the year ended December 31, 2015 from $22.3 million for the year ended December 31, 2014. Increased expenses in 2015 primarily includes the $19.1 million increase in third-party services and other expenses relating largely to the advancement of our CPM antibody programs, our $13.2 million asset acquisition which was expensed as in-process research and development, a $5.6 million increase in payroll related costs due to increased headcount, and $3.6 million in one-time license technology fees.

General and Administrative: General and administrative expenses consist primarily of personnel costs, facility expenses, and professional fees. General and administrative expenses increased 34% to $28.4 million for the year ended December 31, 2015 from $21.2 million for the year ended December 31, 2014. Increased general and administrative expenses in 2015 primarily relate to a $4.1 million increase in professional fees related to our corporate activities, $1.3 million increase in payroll related expenses due to increased headcount and $1.4 million increase in share-based compensation.

Contingent purchase price consideration fair value adjustment: Contingent purchase price consideration fair value adjustment represents the change in the fair value of our purchase price consideration during the year ended December 31, 2015 which resulted in expense of $6.7 million related to the changes in our market capitalization, including the achievement of the first milestone under our 4-AB Share Exchange Agreement. The fair value of our contingent purchase price consideration is based on estimates from a Monte Carlo simulation of our market capitalization.

Non-operating (expense)income:  Non-operating expense for the year ended December 31, 2015 represents the change in the fair value of our contingent royalty obligation of $6.9 million, our foreign currency exchange loss and our loss on extinguishment of our 2013 Notes offset by the $1.5 million gain on the purchase related to the antibody manufacturing facility acquisition from XOMA Corporation in December 2015 described in Note 4 to the consolidated financial statements included elsewhere in this Annual Report on Form 10-K. Non-operating income for the year ended December 31, 2014 represents primarily the decrease in the fair value of our contingent royalty obligation due to the termination of GSK’s Phase 3 MAGE-A3 trial in non-small cell lung cancer, which occurred during the first quarter of 2014.

Interest Expense, net: Interest expense, net increased to $6.6 million for the year ended December 31, 2015 from $1.3 million for the year ended December 31, 2014 due to the issuance of our 2015 Subordinated Notes in February 2015 and the issuance of the Notes under our NPA which was executed in September 2015.

Income tax benefit: For the year ended December 31, 2015, an income tax benefit arose from deferred tax liabilities recognized in connection with our PhosImmune and XOMA acquisitions during the year and relates to the resulting release of our existing valuation allowance on our deferred tax assets.

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Year Ended December 31, 2014 Compared to the Year Ended December 31, 2013

Revenue: We generated revenue of $7.0 million and $3.0 million during the years ended December 31, 2014 and 2013, respectively. Revenue primarily includes license fees earned, in 2014, grant revenue, and in 2013, service revenue. The increase in revenue for the year ended December 31, 2014 is primarily attributable to (i) the amortization of deferred revenue associated with the acquisition of 4-AB and (ii) a milestone payment received. During the years ended December 31, 2014 and 2013, we recorded revenue of $3.5 million and $1.6 million, respectively, from the amortization of deferred revenue.

Research and Development: Research and development expense increased 72% to $22.3 million for the year ended December 31, 2014 from $13.0 million for the year ended December 31, 2013. Increased expenses in 2014 primarily relate to the $2.2 million increase in third-party services and other expenses relating largely to the advancement of our CPM antibody programs and a $4.0 million increase in payroll related costs due to increased headcount, in each case as a result of the acquisition of 4-AB.

General and Administrative: General and administrative expenses increased 47% to $21.2 million for the year ended December 31, 2014 from $14.5 million for the year ended December 31, 2013. Increased expenses in 2014 primarily related to $2.9 million increase in professional fees related to our corporate activities, and $1.9 million increase in payroll related expenses due to increased headcount as a result of the acquisition of 4-AB.

Contingent purchase price consideration fair value adjustment: Contingent purchase price consideration fair value adjustment represents the increase in the fair value of our contingent purchase price consideration issued in connection with our acquisition of 4-AB during the year ended December 31, 2014. The fair value of our contingent purchase price consideration is based on estimates from a Monte Carlo simulation of our market capitalization and increased primarily due to an increase in our market capitalization from the initial valuation during February 2014 to December 31, 2014.

Non-operating (expense) income: Non-operating income for the year ended December 31, 2014 represents primarily the decrease in the fair value of our contingent royalty obligation due to the termination of GSK’s Phase 3 MAGE-A3 trial in non-small cell lung cancer, which occurred during the first quarter of 2014. For the year ended December 31, 2013, the non-operating expense resulted primarily from the loss on extinguishment of our convertible notes of approximately $3.3 million.

Interest Expense, net: Interest expense decreased to $1.3 million for the year ended December 31, 2014 from $2.4 million for the year ended December 31, 2013 due to the extinguishment of our 2006 Notes during 2013.

Dividends on Series A and A-1 convertible preferred stock: Dividends decreased to approximately $204,000 for the year ended December 31, 2014 from approximately $3.2 million for the year ended December 31, 2013 due to the deemed dividend of 666,666 shares of our common stock issued during the exchange of the Series A for Series A-1 convertible preferred stock during the quarter ended March 31, 2013 and the related reduced dividend obligation subsequent to that exchange.

Inflation

We believe that inflation has not had a material adverse effect on our business, results of operations, or financial condition to date.

Research and Development Programs

For the year ended December 31, 2015, our research and development programs consisted largely of our CPM antibody programs as indicated in the following table (in thousands). 

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Research and development program costs include compensation and other direct costs plus an allocation of indirect costs, based on certain assumptions and our review of the status of each program. Our product candidates are in various stages of development and significant additional expenditures will be required if we start new clinical trials, encounter delays in our programs, apply for regulatory approvals, continue development of our technologies, expand our operations, and/or bring our product candidates to market. The total cost of any particular clinical trial is dependent on a number of factors such as trial design, length of the trial, number of clinical sites, number of patients, and trial sponsorship. The process of obtaining and maintaining regulatory approvals for new therapeutic products is lengthy, expensive, and uncertain. Because our CPM antibody programs are pre-clinical and early stage, and because further development of HSP-based vaccines is dependent clinical trial results, among other factors, we are unable to reliably estimate the cost of completing our research and development programs or the timing for bringing such programs to various markets or substantial partnering or out-licensing arrangements, and, therefore, when, if ever, material cash inflows are likely to commence.  Active programs involving QS-21 Stimulon depend on our collaboration partners or licensees successfully completing clinical trials, successfully manufacturing QS-21 Stimulon to meet demand, obtaining regulatory approvals and successfully commercializing product candidates containing QS-21 Stimulon.

Product Development Portfolio

Antibody Discovery Platforms and CPM Programs

In February 2014, we acquired our Retrocyte Display platform when we acquired 4-Antibody AG (“4-AB”), a private European-based biopharmaceutical company. Retrocyte Display (Retroviral B Lymphocyte Display) is a proprietary antibody discovery platform designed for the rapid discovery and optimization of fully-human and humanized monoclonal antibodies against a wide array of molecular targets. Our Retrocyte Display platform uses a high-throughput approach incorporating human antibody libraries expressed in mammalian B-lymphocytes and is designed to screen and generate therapeutic antibody drug candidates. We complimented this platform in April 2015 with the acquisition of our SECANT yeast display antibody discovery platform from Celexion, LLC, and in September 2015 with the exclusive license to a phage display library. The addition of the phage display library and SECANT yeast display platform in combination with our Retrocyte Display platform gives us broad, integrated and highly productive antibody discovery platforms. Each of these complementary platforms is designed to yield diverse antibody candidates, and together they increase the variety of addressable targets and diversity of antibody candidates. These approaches are intended to combine the speed, diversity, and selectivity of our discovery platforms to yield high affinity antibodies and bolster our antibody discovery capabilities internally and for our partners. We now have the potential to integrate three high quality complementary antibody display technologies with innovative computational, structured-based design approaches to discover and optimize best-in-class monoclonal antibodies as future medicines.

We and our partners currently have pre-clinical and clinical programs exploring fully human and humanized monoclonal antibodies against several important checkpoint targets including: GITR, OX40, CTLA-4, PD-1, TIM-3, LAG-3, CEACAM1 and other undisclosed targets. In 2015, we filed INDs for antibodies targeting CTLA-4 and GITR (filed with Incyte), and in January 2016 we announced that the U.S. Food & Drug Administration (FDA) gave clearance to begin clinical trials with these two CPM candidates. Clinical trials with these CPMs are planned to initiate in the first half of 2016. In addition, we have product candidates targeting OX40 and PD-1 advancing into IND-enabling studies, and we expect to initiate clinical trials for one or more of these compounds during the second half of 2016. For additional information regarding our antibody discovery platforms and checkpoint antibody program, please read Part I-Item 1. “Business” of this Annual Report on Form 10-K.

Prophage Vaccine Candidates

To date, more than 1,000 cancer patients have been treated with Prophage vaccines, covering a broad range of cancer types in many clinical trials. The results of these trials have been published and/or presented at major conferences. These results indicate observable clinical and/or immunological activity across many types of cancer.

Because Prophage vaccine are novel therapeutic vaccines that are patient-specific, meaning derived from the patient’s own tumor, they are experiencing a long development process and high development costs, either of which could delay or prevent our commercialization efforts.

In addition to the Phase 2 trial in patients with newly diagnosed GBM, the Alliance for Clinical Trials in Oncology, a cooperative group of the National Cancer Institute, or NCI, is supporting a randomized Phase 2 clinical trial of the Prophage vaccine in combination with bevacizumab in 222 patients with surgically resectable, recurrent GBM. This trial is the largest vaccine trial ever funded by the NCI in brain tumors and the largest vaccine study ever conducted in combination with bevacizumab. The study is designed to compare efficacy of the Prophage vaccine administered with bevacizumab either concomitantly or at progression, as compared to treatment with bevacizumab alone. The primary endpoint of this study is overall survival. This study design is supported in part by previous research indicating a potential synergistic effect between the mechanisms of action behind both the Prophage vaccine and bevacizumab. While the NCI Alliance has confirmed a commitment to completion of the trial, to date, it has been slow to recruit patients. For additional information regarding regulatory risks and uncertainties, please read the risks identified under Part I-Item 1A. “Risk Factors” of this Annual Report on Form 10-K.

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AutoSynVax (ASV)Vaccine Program

In June 2014 we reported positive results from a Phase 2 clinical trial with our synthetic HerpV vaccine candidate for genital herpes. This candidate was the first potential recombinant, off-the-shelf application of our HSP technology. The study demonstrated that the HSP70-peptide-QS21 vaccine produced significant CD8 and CD4 positive T-cell responses to antigenic peptides, and that the side effects were mild to moderate and tolerable. We decided not to advance with this technology in herpes, and based on our findings we launched our AutoSynVax synthetic cancer vaccine program in 2015. We plan to initiate clinical trials for this program in the second half of 2016.

The objective of our AutoSynVax, or ASV, program is to develop a fully synthetic, yet individual patient specific tumor vaccine targeting the neo-epitope landscape of each patient’s cancer. With a small amount of a patient’s tumor as a sample, our ASV program is designed to utilize highly complex bioinformatics and next generation sequencing technologies to identify mutations in a tumor’s DNA and RNA. Once these mutations have been identified, we will manufacture synthetic peptides, load these peptides on to our recombinant HSP70 and deliver a fully synthetic polyvalent vaccine to the patient. We believe that the HSP70 platform will shuttle the mutated peptides to sites where they are recognized by the immune system and safely elicit a cytotoxic and helper T cell response in patients with cancer. We expect that once identified, these tumor cells will be killed and cleared by the immune system.  For additional information regarding HerpV and AutoSynVax, please read Part I-Item 1. “Business” of this Annual Report on Form 10-K.

PhosphoSynVax (PSV) Vaccine Candidate

PSV is a vaccine candidate designed to induce immunity against a novel class of tumor specific neo-epitopes: those arising from dysregulated phosphorylation of various proteins in malignant cells, rather than from mutations producing abnormal protein sequences. In cancer cells, protein sequences that can become phosphorylated (a phosphate group is added to particular amino acid residues) that are not normally phosphorylated, as a consequence of dysregulated biochemical processes. Some of these mis-phosphorylated peptides can be processed by the cellular machinery that leads to antigen presentation of the surface of cells, and there they can potentially be recognized by specific cytotoxic T cells. PhosImmune described many hundreds of such phosphoprotein neo-epitopes characterizing different forms of cancer, such as lung cancer, specific leukemias, ovarian cancer, colon cancer and others. When this happens, it can lead to the destruction of the cancer cells. PSV is a group of potential product candidates intended to induce cellular immunity to abnormal phosphopeptide neo-epitopes characterizing various forms of cancer. Phosphopeptides (or phosphopeptide analogues) can be synthesized and complexed with HSP70, in a manner analogous to that used in the generation of Agenus’ previous HerpV vaccine candidate. HerpV has successfully completed a placebo-controlled Phase 2 study, which demonstrated good cellular and humoral responses to synthetic peptide immunogens complexed with HSP70. We believe that similar responses can be obtained to phosphopeptide or phosphopeptide analogues bound to HSP70 used as vaccines. Mutation-based neo-epitopes, which will form the basis for the immunogens used in ASV, are almost always particular to a given patient. Therefore, ASV will need to be a largely individualized vaccine product. In contrast to this, some phosphorylation-based neo-epitopes are apparently found on specific types of cancer in many patients, suggesting that the immunogens used in PSV, while tailored to a particular patient, will be useful in other patients with related forms of cancer. Studies to optimize the immunogens to be used in PSV are on-going. PSV could prove to be particularly useful in enabling activation of immunity against cancer that contains fewer mutation-based neo-epitopes.  For additional information regarding PhosphoSynVax, please read Part I-Item 1. “Business” of this Annual Report on Form 10-K.

QS-21 Stimulon

QS-21 Stimulon is an adjuvant, or a substance added to a vaccine or other immunotherapy, that is intended to enhance immune response to the target antigens. The primary corporate licensee of QS-21 Stimulon is GSK. There are several vaccines containing QS-21 Stimulon in clinical development, including two that have successfully completed Phase 3 testing by GSK for malaria and shingles. Assuming regulatory approval, the first products containing QS-21 Stimulon are anticipated to be launched in 2018, and we are generally entitled to royalties for at least ten years after commercial launch, with some exceptions. In September 2015, we monetized a portion of these royalties to an investors group for up to $115.0 million.  Under the terms of this transaction, the investors have the right to receive royalties earned on sales of the malaria and shingles vaccines to pay down principal and interest. We do not incur clinical development costs for these products of our licensees. For additional information regarding QS-21 Stimulon, please read Part I-Item 1. “Business” of this Annual Report on Form 10-K.

Liquidity and Capital Resources

We have incurred annual operating losses since inception, and we had an accumulated deficit of $779.2 million as of December 31, 2015. We expect to incur significant losses over the next several years as we continue development of our technologies and product candidates, manage our regulatory processes, initiate and continue clinical trials, and prepare for potential commercialization of products. To date, we have financed our operations primarily through the sale of equity and debt securities, and interest income earned on cash, cash equivalents, and short-term investment balances. From our inception through December 31, 2015, we have raised

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aggregate net proceeds of approximately $839.0 million through the sale of common and preferred stock, the exercise of stock options and warrants, proceeds from our employee stock purchase plan, and the issuance of convertible and other notes. In February 2015, we received aggregate proceeds of $60.0 million through our collaboration and stock purchase agreements with Incyte Corporation and issued $9.0 million in new 2015 Subordinated Notes. In May 2015, we received net proceeds of approximately $75.0 million through an underwritten public offering of approximately 12,650,000 shares of our common stock after deducting underwriting discounts and commissions and offering expenses (the "May 2015 Public Offering"). In September 2015, we received net proceeds of approximately $78.0 million from Antigenics’ issuance of limited recourse notes under the Note Purchase Agreement (NPA) with Oberland and the other purchasers.

We also maintain an effective registration statement (the "Shelf Registration Statement"), which originally covered the offering of up to $150.0 million of common stock, preferred stock, warrants, debt securities and units. The Shelf Registration was used to complete the May 2015 Public Offering, and as of December 31, 2015, $70.3 million remained available thereunder. The Shelf Registration Statement includes a prospectus covering the offering, issuance and sale of up to ten million shares of our common stock from time to time in “at the market offerings” pursuant to an At Market Sales Issuance Agreement (the “Sales Agreement”) entered into with MLV & Co. LLC (the “Sales Agent”). Pursuant to the Sales Agreement, sales will be made only upon instructions by us to the Sales Agent, and we cannot provide any assurances that we will issue any shares pursuant to the Sales Agreement. As of December 31, 2015, we had 10 million shares available for sale under the Sales Agreement.

As of December 31, 2015, we had debt outstanding of $114.1 million in principal. In April 2013, we entered into a Note Purchase Agreement with various investors for senior subordinated notes (the “2013 Notes”) in the aggregate principal amount of $5.0 million due in April 2015.  In February 2015, we exchanged the 2013 Notes for new senior subordinated notes (the "2015 Subordinated Notes") in the aggregate principal amount of $5.0 million with annual interest at 8% and also issued additional 2015 Subordinated Notes in the aggregate principal amount of $9.0 million, such notes are due February 2018.  In addition, we also issued to the holders of the 2015 Subordinated Notes five year warrants to purchase 1.4 million unregistered shares of our common stock at an exercise price of $5.10 per share. In September 2015, we and Antigenics entered into a Note Purchase Agreement with Oberland pursuant to which Antigenics issued, and we guaranteed, limited recourse notes in the aggregate principal amount of $100.0 million, with an option to issue an additional $15.0 million principal amount of limited recourse notes.  The limited recourse notes are due on the earlier of (i) the 10^th anniversary of the first commercial sale of GSK’s shingles or malaria vaccines and (ii) September 8, 2030.

Our cash, cash equivalents, and short-term investments at December 31, 2015 were $171.7 million, an increase of $131.4 million from December 31, 2014, principally as a result of (i) our collaboration and stock purchase agreements with Incyte which generated aggregate proceeds of $60.0 million, (ii) our 2015 Subordinated Notes which generated an aggregate of $9.0 million of new proceeds, (iii) our May 2015 Public Offering in which we received net proceeds of approximately $75.0 million and (iv) our NPA in which we generated net proceeds of approximately $78.0 million. We believe that, based on our current plans and activities, our cash, cash equivalents, and short-term investments of $171.7 million as of December 31, 2015 will be sufficient to satisfy our liquidity requirements through the first half of 2017. We continue to monitor the likelihood of success of our key initiatives and are prepared to discontinue funding of such activities if they do not prove to be feasible, restrict capital expenditures and/or reduce the scale of our operations.

We expect to attempt to raise additional funds in advance of depleting our current funds. We may attempt to raise funds by: (1) pursuing collaboration, out-licensing and/or partnering opportunities for our portfolio programs and product candidates with one or more third parties, (2) renegotiating third party agreements, (3) selling assets, (4) securing additional debt financing and/or (5) selling equity securities. Satisfying long-term liquidity needs may require the successful commercialization and/or substantial out-licensing or partnering arrangements for our antibody discovery platforms, CPM antibody programs, HSP-based vaccines, and vaccines containing QS-21 Stimulon under development by our licensees. Our long-term success will also be dependent on the successful identification, development and commercialization of potential other product candidates, each of which will require additional capital with no certainty of timing or probability of success. If we incur operating losses for longer than we expect and/or we are unable to raise additional capital, we may become insolvent and be unable to continue our operations.

Our future cash requirements include, but are not limited to, supporting clinical trial and regulatory efforts and continuing our other research and development programs. Since inception, we have entered into various agreements with contract manufacturers, institutions, and clinical research organizations (collectively "third party providers") to perform pre-clinical activities and to conduct and monitor our clinical studies. Under these agreements, subject to the enrollment of patients and performance by the applicable third party provider, we have estimated our total payments to be $78.0 million over the term of the related activities. Through December 31, 2015, we have expensed $71.3 million as research and development expenses and $65.0 million has been paid under these agreements. The timing of expense recognition and future payments related to these agreements is subject to the enrollment of patients and performance by the applicable third party provider. We have also entered into sponsored research agreements related to our product candidates that required payments of $6.7 million, all of which have been paid as of December 31, 2015. We plan to enter into additional agreements with third party providers as well as sponsored research agreements, and we anticipate significant additional expenditures will be required to initiate and advance our various programs.

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Part of our strategy is to develop and commercialize some of our product candidates by continuing our existing collaboration arrangements with academic and collaboration partners and licensees and by entering into new collaborations. As a result of our collaboration agreements, we will not completely control the efforts to attempt to bring those product candidates to market. For example, our collaboration with Incyte for the development, manufacture and commercialization of CPM antibodies against certain targets is managed by a joint steering committee with equal representation from Agenus and Incyte. We also have agreements with licensees that allow the use of our QS-21 Stimulon adjuvant in numerous vaccines, which grant exclusive worldwide rights in some fields of use and co-exclusive or non-exclusive rights in others. These agreements generally call for royalties to be paid to us on future sales of licensed products that result from these agreements, which may or may not be achieved. As noted above, in September 2015 we monetized the anticipated royalties related to GSK’s shingles and malaria vaccines through our NPA with Oberland and the other purchasers.

Net cash used in operating activities for the years ended December 31, 2015 and 2014 was $47.2 million and $38.2 million, respectively. We continue to support and develop our QS-21 Stimulon partnering collaborations. If applications for marketing approval of vaccines that are submitted by our licensees are approved, the first products containing QS-21 Stimulon are anticipated to be launched in 2018. We are generally entitled to royalties on sales by our licensees of vaccines using QS-21 Stimulon for at least ten years after commercial launch, with some exceptions. In September 2015, we entered into a Note Purchase Agreement and partially monetized the potential royalties we are entitled to receive from GSK. Our future ability to generate cash from operations will depend on achieving regulatory approval and market acceptance of our product candidates, achieving benchmarks as defined in existing collaboration agreements, and our ability to enter into new collaborations. Under our Collaboration Agreement with Incyte, we are required to share costs with Incyte on a 50:50 basis under the GITR and OX40 programs as well as the two additional undisclosed programs nominated for development during 2015; there is a potential for these costs to be high and the development program budgets for these antibodies to not be in our complete control. Please see the “Note Regarding Forward-Looking Statements” of this Annual Report on Form 10-K and the risks highlighted under Part I-Item 1A. “Risk Factors” of this Annual Report on Form 10-K.

The table below summarizes our contractual obligations as of December 31, 2015 (in thousands).

Off-Balance Sheet Arrangements

At December 31, 2015, we had no off-balance sheet arrangements.

Critical Accounting Policies and Estimates

The SEC defines “critical accounting policies” as those that require the application of management’s most difficult, subjective, or complex judgments, often as a result of the need to make estimates about the effect of matters that are inherently uncertain and may change in subsequent periods.

The preparation of consolidated financial statements in conformity with U.S. generally accepted accounting principles requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. We base those estimates on historical experience and on various assumptions that are believed to be reasonable under the circumstances. Actual results could differ from those estimates.

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The following listing is not intended to be a comprehensive list of all of our accounting policies. Our significant accounting policies are described in Note 2 of the notes to our consolidated financial statements contained elsewhere in this Annual Report on Form 10-K. In many cases, the accounting treatment of a particular transaction is dictated by U.S. generally accepted accounting principles, with no need for our judgment in its application. There are also areas in which our judgment in selecting an available alternative would not produce a materially different result. We have identified the following as our critical accounting policies.

Share-Based Compensation

In accordance with the fair value recognition provisions of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 718, Compensation—Stock Compensation, we recognize share-based compensation expense net of an estimated forfeiture rate and only recognize compensation expense for those share-based awards expected to vest. Compensation expense is recognized on a straight-line basis over the requisite service period of the award.

Share-based awards granted to certain non-employees have been accounted for based on the fair value method of accounting in accordance with ASC 505-50, Equity- Equity-Based Payments to Non-Employees. As a result, the non-cash charge to operations for non-employee awards with vesting or other performance criteria is affected each reporting period by changes in the fair value of our common stock. Under the provisions of ASC 505-50, the change in fair value of vested awards issued to non-employees is reflected in the statement of operations each reporting period, until the options are exercised or expire.

Determining the appropriate fair value model and calculating the fair value of share-based awards requires the use of highly subjective assumptions, including the expected life of the share-based awards and stock price volatility. The assumptions used in calculating the fair value of share-based awards represent management’s best estimates, but these estimates involve inherent uncertainties and the application of management judgment. As a result, if factors change and we use different assumptions, our share-based compensation expense could be materially different in the future. For performance condition awards, we estimate the probability that the performance condition will be met. In addition, if our actual forfeiture rate is materially different from our estimate, the share-based compensation expense could be significantly different from what we have recorded in the current period. See Note 11 of the notes to our consolidated financial statements contained elsewhere in this Annual Report on Form 10-K for a further discussion on share-based compensation.

Revenue Recognition

Revenue recognized from collaborative agreements is based upon the provisions of ASC 605-25, Revenue Recognition—Multiple Element Arrangements, as amended by Accounting Standards Update 2009-13. License fees and royalties are recognized as they are earned.  Non-refundable milestone payments that represent the completion of a separate earnings process are recognized as revenue when earned.  Revenue for services under research and development contracts are recognized as the services are performed, or as clinical trial materials are provided.

Fair Value Measurements

In accordance with ASC 820, Fair Value Measurements and Disclosures, we measure fair value based on a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that observable inputs be used when available. The fair value hierarchy is broken down into three levels based on the source of inputs.

We measured our contingent royalty obligation and currently measure our contingent purchase price considerations at fair value in accordance with ASC 825, Financial Instruments. The fair value of our contingent royalty obligation and contingent purchase price considerations are based on significant inputs not observable in the market, which require them to be reported as a Level 3 liability within the fair value hierarchy. The valuation of these liabilities uses assumptions we believe would be made by a market participant. In particular, the valuation analysis for the contingent royalty obligation used the income approach based on the sum of the economic income that an asset is anticipated to produce in the future. In this case that asset was the potential royalty income to be paid to us as a result of certain license agreements for QS-21 Stimulon and the potential net sales generated from HerpV. The fair value of the contingent royalty obligation was estimated by applying a risk adjusted discount rate to the probability adjusted royalty revenue stream based on expected approval dates. These fair value estimates are most sensitive to changes in the probability of regulatory approvals. The discounted cash flow method of the income approach was chosen as the method best suited to valuing the contingent royalty obligation.

The fair values of our 4-AB and PhosImmune contingent purchase price considerations are based on estimates from a Monte Carlo simulation of our market capitalization and share price, respectively. Market capitalization and share price were evolved using a geometric brownian motion, calculated daily for the life of the contingent purchase price consideration.  

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Business Combinations

In February 2014 and December 2015, we acquired all of the outstanding capital stock of 4-AB and PhosImmune, respectively in business combination transactions. In December 2015, we also acquired an antibody manufacturing pilot facility from XOMA Corporation which under the applicable accounting guidance is being accounted for as a business combination.  The acquisition method of accounting requires that the assets acquired and liabilities assumed be recorded as of the date of the merger or acquisition at their respective fair values with limited exceptions. Assets acquired and liabilities assumed in a business combination that arise from contingencies are recognized at fair value if fair value can reasonably be estimated. If the acquisition date fair value of an asset acquired or liability assumed that arises from a contingency cannot be determined, the asset or liability is recognized if probable and reasonably estimable; if these criteria are not met, no asset or liability is recognized. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Accordingly, we may be required to value assets at fair value measures that do not reflect our intended use of those assets. Any excess of the purchase price (consideration transferred) over the estimated fair values of net assets acquired is recorded as goodwill. In the event the value of the net assets acquired exceeds the purchase price consideration, then a bargain purchase has occurred. The resulting bargain purchase on the transaction will be recognized as a gain in the period in which the acquisition was executed. The operating results of the acquired businesses are reflected in our consolidated financial statements after the date of the merger or acquisition. If we determine the assets acquired do not meet the definition of a business under the acquisition method of accounting, the transaction will be accounted for as an acquisition of assets rather than a business combination and, therefore, no goodwill will be recorded. The fair values of intangible assets, including acquired in-process research and development (“IPR&D”), are determined utilizing information available near the merger or acquisition date based on expectations and assumptions that are deemed reasonable by management. The judgments made in determining estimated fair values assigned to assets acquired and liabilities assumed in a business combination, as well as asset lives, can materially affect the Company’s results of operations.

Acquired Intangible Assets, including IPR&D

IPR&D acquired in a business combination represents the fair value assigned to research and development assets that have not reached technological feasibility. The value assigned to acquired IPR&D is determined by estimating the costs to develop the acquired technology into commercially viable products, estimating the resulting revenue from the projects, and discounting the net cash flows to present value. The revenue and costs projections used to value acquired IPR&D are, as applicable, reduced based on the probability of success of developing a new drug. Additionally, the projections consider the relevant market sizes and growth factors, expected trends in technology, and the nature and expected timing of new product introductions by us and our competitors. The rates utilized to discount the net cash flows to their present value are commensurate with the stage of development of the projects and uncertainties in the economic estimates used in the projections. Upon the acquisition of IPR&D, we complete an assessment of whether our acquisition constitutes the purchase of a single asset or a group of assets. We consider multiple factors in this assessment, including the nature of the technology acquired, the presence or absence of separate cash flows, the development process and stage of completion, quantitative significance and our rationale for entering into the transaction.

We review amounts capitalized as acquired IPR&D for impairment at least annually, as of October 31, and whenever events or changes in circumstances indicate that the carrying value of the assets might not be recoverable. When performing our impairment assessment, we have the option to first assess qualitative factors to determine whether it is necessary to recalculate the fair value of our acquired IPR&D. If we elect this option and believe, as a result of the qualitative assessment, that it is more-likely-than-not that the fair value of our acquired IPR&D is less than its carrying amount, we calculate the fair value using the same methodology as described above. If the carrying value of our acquired IPR&D exceeds its fair value, then the intangible asset is written-down to its fair value. Alternatively, we may elect to bypass the qualitative assessment and immediately recalculate the fair value of our acquired IPR&D.

Goodwill

Goodwill was $22.8 million at December 31, 2015. Goodwill is tested at least annually for impairment on a reporting unit basis. We have concluded that we consist of a single operating segment and one reporting unit. We assess goodwill for impairment by performing a quantitative analysis to determine whether the fair value of our single reporting unit exceeds its carrying value. We perform our annual impairment test as of October 31 of each year and the first step of our impairment analysis compares the fair value to our net book value to determine if there is an indicator of impairment. Fair value is based on the quoted market price of our common stock to derive the market capitalization as of the date of the impairment test.

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Recent Accounting Pronouncements

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, ("ASU 2014-09"). ASU 2014-09 amends revenue recognition principles and provides a single set of criteria for revenue recognition among all industries. This new standard provides a five step framework whereby revenue is recognized when promised goods or services are transferred to a customer at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard also requires enhanced disclosures pertaining to revenue recognition in both interim and annual periods. ASU 2014-09 is effective for interim and annual periods beginning after December 15, 2017. We are currently evaluating the potential impact that ASU 2014-09 may have on our financial position and results of operations.

In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern, ("ASU 2014-15").  ASU 2014-15 describes how an entity should assess its ability to meet obligations and sets rules for how this information should be disclosed in the financial statements.  The standard provides accounting that will be used along with existing auditing standards.  ASU 2014-15 applies to all entities and is effective for the annual period ending after December 15, 2016, and for annual and interim periods thereafter with early adoption permitted. We are currently evaluating the potential impact that ASU 2014-15 may have on our consolidated financial statements and related disclosures.

In April 2015, the FASB issued ASU No. 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs, (“ASU 2015-03”).  ASU 2015-03 simplifies the presentation of debt issuance costs, as this new standard requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by this update. This guidance is effective for annual reporting beginning after December 15, 2015, including interim periods within the year of adoption, and calls for retrospective application, with early application permitted.  We adopted ASU 2015-03 with the interim period ended September 30, 2015. During the year ended December 31, 2015, in connection with the execution of the NPA as described in Note 16, the Company incurred approximately $1.5 million in debt issuance costs that are classified as a reduction to long-term debt in our consolidated balance sheet. No debt issuance costs required retrospective application as the result of the adoption of ASU 2015-03. The amortization of the debt issuance costs for the year ended December 31, 2015 was not material.

In November 2015, the FASB issued ASU No. 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes, (“ASU 2015-17”).  ASU 2015-17 requires entities with a classified balance sheet to present all deferred tax assets and liabilities as noncurrent. ASU 2015-17 is effective for public business entities for interim and annual periods in fiscal years beginning after December 15, 2016. Early adoption is permitted. We early adopted ASU 2015-17 for the year ended December 31, 2015. The adoption of ASU 2015-17 did not have a material impact on our consolidated balance sheets.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) (“ASU 2016-2”) which supersedes Topic 840, Leases. ASU2016-02 requires lessees to recognize a right-of-use asset and a lease liability on their balance sheets for all leases with terms greater than twelve months. Based on certain criteria, leases will be classified as either financing or operating, with classification affecting the pattern of expense recognition in the income statement. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. If a lessee makes this election, it should recognize lease expense for such leases generally on a straight-line basis over the lease term. ASU 2016-2 is effective for fiscal years beginning after December 15, 2018, and interim periods within those years, with early adoption permitted. In transition, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients primarily focused on leases that commenced before the effective date of Topic 842, including continuing to account for leases that commence before the effective date in accordance with previous guidance, unless the lease is modified. We are evaluating the impact of the adoption of the standard on our consolidated financial statements.

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Our primary market risk exposure is foreign currency exchange rate risk. International revenues and expenses are generally transacted by our foreign subsidiary and are denominated in local currency. Approximately 4% and 32% of our cash used in operations for the years ended December 31, 2015 and 2014, respectively, was from a foreign subsidiary. Additionally, in the normal course of business, we are exposed to fluctuations in interest rates as we seek debt financing and invest excess cash. We are also exposed to foreign currency exchange rate fluctuation risk related to our transactions denominated in foreign currencies. We do not currently employ specific strategies, such as the use of derivative instruments or hedging, to manage these exposures. Our currency exposures vary, but are primarily concentrated in the Euro and Swiss Franc, in large part due to our wholly-owned subsidiary, 4-AB, a company with operations in Switzerland and Germany. During the year ended December 31, 2015, there has been no material change with respect to our approach toward those exposures.

We had cash, cash equivalents and short-term investments at December 31, 2015 of $171.7 million, which are exposed to the impact of interest and foreign currency exchange rate changes, and our interest income fluctuates as interest rates change. Due to the short-term nature of our investments in money market funds and US Treasury Securities, our carrying value approximates the fair value of these investments at December 31, 2015, however, we are subject to investment risk.

We invest our cash and cash equivalents in accordance with our investment policy. The primary objectives of our investment policy are to preserve principal, maintain proper liquidity to meet operating needs, and maximize yields. We review our investment policy annually and amend it as deemed necessary. Currently, the investment policy prohibits investing in any structured investment vehicles and asset-backed commercial paper. Although our investments are subject to credit risk, our investment policy specifies credit quality standards for our investments and limits the amount of credit exposure from any single issue, issuer, or type of investment. We do not invest in derivative financial instruments. Accordingly, we do not believe that there is currently any material market risk exposure with respect to derivatives or other financial instruments that would require disclosure under this item.

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INDEX TO FINANCIAL STATEMENTS

53

Report of Independent Registered Public Accounting Firm

The Board of Directors and Stockholders

Agenus Inc.:

We have audited the accompanying consolidated balance sheets of Agenus Inc. and subsidiaries (the Company) as of December 31, 2015 and 2014, and the related consolidated statements of operations and comprehensive loss, stockholders’ equity (deficit), and cash flows for each of the years in the three-year period ended December 31, 2015. These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of Agenus Inc. and subsidiaries as of December 31, 2015 and 2014, and the results of their operations and their cash flows for each of the years in the three-year period ended December 31, 2015, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), Agenus Inc. and subsidiaries’ internal control over financial reporting as of December 31, 2015, based on criteria established in Internal Control-Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO), and our report dated March 15, 2016 expressed an unqualified opinion on the effectiveness of the Company’s internal control over financial reporting.

/s/ KPMG LLP

Boston, Massachusetts

March 15, 2016

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AGENUS INC. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

See accompanying notes to consolidated financial statements.

55

AGENUS INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

For the Years Ended December 31, 2015, 2014, and 2013

See accompanying notes to consolidated financial statements.

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AGENUS INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT)

For the Years Ended December 31, 2015, 2014, and 2013