CURIS INC - Annual Report: 2011 (Form 10-K)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark one)

For the fiscal year ended December 31, 2011

OR

Commission File Number 000-30347

CURIS, INC.

(Exact Name of Registrant as Specified in Its Charter)

4 Maguire Road

Lexington, Massachusetts 02421

(Address of principal executive offices) (Zip Code)

617-503-6500

(Registrant’s telephone number, including area code)

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  ¨    No  x

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  ¨    No  x

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.    x  Yes    ¨  No

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 Regulation 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).    x  Yes    ¨  No

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K 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.    ¨

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 Act).    Yes  ¨    No  x

The aggregate market value of the registrant’s common stock held by non-affiliates of the registrant (without admitting that any person whose shares are not included in such calculation is an affiliate) based on the last reported sale price of the common stock on June 30, 2011 was approximately $188,823,000.

As of February 24, 2012, there were 77,512,426 shares of the registrant’s common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Specified portions of the registrant’s proxy statement for the annual meeting of stockholders scheduled to be held on May 30, 2012, which are to be filed with the Commission not later than 120 days after the close of the Registrant’s fiscal year ended December 31, 2011 pursuant to Regulation 14A, have been incorporated by reference in Item 5 of Part II and Items 10-14 of Part III of this Annual Report on Form 10-K.

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CURIS, INC.

TABLE OF CONTENTS

Form 10-K

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PART I

This annual report on Form 10-K contains forward-looking statements that involve risks and uncertainties, as well as assumptions that, if they never materialize or prove incorrect, could cause Curis’ financial, operating and business results to differ materially from those expressed or implied by such forward-looking statements. All statements other than statements of historical fact are statements that could be deemed forward-looking statements, including without limitation any expectations of revenue, expenses, earnings or losses from operations, or other financial results; statements with respect to the plans, strategies and objectives of management for future operations; statements concerning product research, development and commercialization plans, timelines and anticipated results; statements of expectation or belief; and statements of assumptions underlying any of the foregoing. The risks, uncertainties and assumptions referred to above include risks that are described in “Item 1A-Risk Factors” and elsewhere in this annual report and that are otherwise described from time to time in our Securities and Exchange Commission reports filed after this report.

The forward-looking statements included in this annual report represent our estimates as of the filing date of this annual report. We specifically disclaim any obligation to update these forward-looking statements in the future. These forward-looking statements should not be relied upon as representing our estimates or views as of any date subsequent to the date of this annual report.

Overview

We are a drug discovery and development company that is committed to leveraging our innovative signaling pathway drug technologies in seeking to develop next generation network-targeted cancer therapies. We are building upon our experience in modulating signaling pathways, including the Hedgehog signaling pathway, in our effort to develop network-targeted cancer therapies. We conduct our research and development programs both internally and through strategic collaborations.

Hedgehog Pathway Inhibitor Program (Erivedge™)

Erivedge™ (vismodegib) capsule. Our most advanced program is our Hedgehog pathway inhibitor program under collaboration with Genentech, Inc., a member of the Roche Group. The lead drug candidate being developed under this program is Erivedge, a first-in-class orally-administered small molecule Hedgehog pathway inhibitor, which is also referred to as vismodegib, GDC-0449 and RG3616. Erivedge is designed to selectively inhibit signaling in the Hedgehog pathway by targeting a protein called Smoothened. The Hedgehog signaling pathway plays an important role in regulating proper growth and development in the early stages of life and becomes less active in adults. However, mutations in the pathway that reactivate Hedgehog signaling are seen in certain cancers, including basal cell carcinoma, or BCC. Abnormal signaling in the Hedgehog pathway is implicated in over 90% of BCC cases.

In January 2012, Erivedge was approved by the U.S. Food and Drug Administration, or FDA, as the first and only FDA-approved medicine for adults with advanced forms of basal cell carcinoma that has spread to other parts of the body or that has come back after surgery or that their healthcare provider decides cannot be treated with surgery or radiation. It is not known if Erivedge is safe and effective in children. We earned a $10,000,000 milestone payment from Genentech as a result of the FDA’s approval of Erivedge in this indication and we are also entitled to receive royalties on future sales of the product. During the fourth quarter of 2011, we received a total of $14,000,000 in milestone payments from Genentech relating to the FDA’s acceptance of Genentech’s New Drug Application, or NDA, for Erivedge and the European Medicines Agency’s, or EMA’s, acceptance for review of a Marketing Authorization Application, or MAA, for Erivedge that was submitted by Roche in December 2011. The Genentech NDA and Roche MAA applications were based on positive clinical data from ERIVANCE BCC/SHH4476g, a pivotal phase II study of Erivedge in patients with advanced BCC. We will receive an additional milestone payment if Erivedge also receives EMA marketing authorization, as well as royalties on any future sales in this territory.

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Genentech is also conducting a separate phase II clinical trial of Erivedge in patients with operable nodular basal cell carcinoma, which is a less severe form of the disease and accounts for a significant percentage of the approximately two million BCCs diagnosed annually in the United States. We anticipate that the study will be completed during early 2013.

In addition to the BCC clinical trials being conducted directly by Genentech and Roche, Erivedge is also currently being tested in other cancers in trials under collaborative agreements between Genentech and either third-party investigators or the U.S. National Cancer Institute, or NCI, including treatment of BCC patients with basal cell nevus syndrome (Gorlin syndrome), medulloblastoma, sarcoma and glioblastoma multiforme, as well as in pancreatic, small cell lung, gastroesophageal junction, gastric, breast, and prostate cancers, among others.

Network-Targeted Cancer Programs

Our internal drug development efforts are focused on our network-targeted cancer programs, in which we are seeking to design single novel small molecule drug candidates that inhibit multiple signaling pathways that are believed to play roles in cancer cell proliferation. We refer to this approach as cancer network disruption. We believe that our approach of targeting multiple nodes in cancer signaling pathway networks may provide a better therapeutic effect than many of the cancer drugs currently marketed or in development since our drug candidates are being designed to disrupt multiple targets in the cancer network environment as compared to many other cancer drugs which are designed to disrupt only one target.

CUDC-101.    Our lead candidate from these programs is CUDC-101, a first-in-class small molecule compound designed to simultaneously target histone deacetylase, or HDAC, epidermal growth factor receptor, or EGFR, and human epidermal growth factor receptor 2, or HER2, all of which are validated cancer targets. A significant amount of our capital resources are focused on the ongoing clinical development of this molecule. To date, we have completed a phase I dose escalation clinical trial of CUDC-101 in 25 patients with advanced, refractory solid tumors and a phase I expansion trial to test CUDC-101 in 46 patients with specific tumor types, including breast, gastric, head and neck, liver and non-small cell lung cancers. The phase I expansion trial was designed as an open-label study in which patients were treated with CUDC-101 at the maximum tolerated dose, which was determined in the phase I dose escalation study to be 275 milligrams per meter². The primary objectives of this study were to compare the safety and tolerability of CUDC-101 in subjects with these specific advanced solid tumors when the drug is administered via one-hour intravenous infusion either on a five days per week schedule (one week on/one week off) or on a three days per week schedule (three weeks on/one week off).

During the third quarter of 2011, we treated the first patient in a phase I clinical trial of CUDC-101 in locally advanced head and neck cancer patients whose cancer is human papilloma virus, or HPV, negative. We have treated four patients in this trial as of February 24, 2012. The primary objective of this study is to evaluate the safety and tolerability of CUDC-101 when administered in combination with the current standard-of-care of cisplatin, a chemotherapeutic drug, and radiation. Upon determination of the maximum tolerated dose and assuming the otherwise successful completion of the phase I trial, we intend to conduct a randomized phase II two-arm clinical trial in which head and neck cancer patients will receive cisplatin and radiation plus or minus CUDC-101. The phase II study would seek to evaluate whether the addition of CUDC-101 can improve the efficacy of cisplatin and radiation therapy in this patient population. We currently estimate that we will initiate the phase II study in the first half of 2013.

We are also working on an oral formulation of CUDC-101, which we believe has the potential to make CUDC-101 more competitive in certain cancers such as non-small cell lung cancer or in other cancers where there are competing investigational or commercially available molecules that are orally administered. Pending the successful completion of ongoing formulation and preclinical development work, we intend to begin a phase I study of an oral formulation of CUDC-101 in the second half of 2012.

CUDC-907.    In January 2011, we selected development candidate CUDC-907, an orally bioavailable, network-targeted small molecule that is designed to inhibit HDAC and phosphatidylinositol-3-kinase, or PI3K.

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Our scientists are developing CUDC-907 based on published and internally generated data demonstrating that HDAC and PI3K inhibitors have synergistic interaction in certain preclinical cancer models. We believe that this synergistic mechanism of cancer signaling network disruption, which demonstrated efficacy and a favorable safety profile in a number of preclinical xenograft models, could translate into clinical advantages over single agents.

In November 2011, we entered into an agreement under which The Leukemia & Lymphoma Society, or LLS, will provide a portion of the funding of the development of CUDC-907 if we succeed in advancing this development candidate into a clinical trial for patients with B-cell lymphoma and multiple myeloma. Pending the successful completion of ongoing formulation and preclinical development work, we expect to file an investigational new drug application, or IND, with the FDA to test an oral formulation of CUDC-907 during the second half of 2012.

In addition to our development-stage programs, we continue to progress additional proprietary preclinical research programs and expect that we will select additional small molecule inhibitors from our preclinical portfolio in the future.

Hsp90 Program

Debio 0932.    Our heat shock protein 90, or Hsp90, program is being developed by Debiopharm, a Swiss pharmaceutical development company, under an August 2009 license agreement between Curis and Debiopharm. The lead molecule under this license collaboration was designated Debio 0932 by Debiopharm. In April 2010, Debiopharm treated the first patient in a phase I clinical trial to evaluate the safety of Debio 0932 in patients suffering from advanced solid tumors. In 2011, Debiopharm successfully advanced Debio 0932 through the dose escalation portion of the phase I study. Debio 0932 was generally well tolerated, with no evidence of ocular or liver toxicity, both of which had been observed in previous clinical testing of certain other Hsp90 inhibitors. Debio 0932 also showed promising signs of efficacy in patients with advanced solid tumors in this study. Debiopharm has indicated that it expects to present phase I data from this phase I study at a medical conference during the first half of 2012.

Debiopharm advanced Debio 0932 into the phase Ib expansion portion of the study in the beginning of 2012. Debiopharm expects to treat approximately 30 patients in this phase Ib study, with the primary objectives of further assessing the safety profile, pharmacokinetics and pharmacodynamics of Debio 0932 at the recommended dose level of 1000mg daily that was established in the dose escalation portion of the Phase I clinical trial, and making a preliminary assessment of anti-tumor activity in patients with advanced solid tumors, including patients with non-small cell lung cancer.

Debiopharm has also indicated that it expects to initiate a combination Phase I/II study in non-small cell lung cancer patients in the second quarter of 2012. We are eligible for our next milestone payment under our license agreement if and when Debiopharm treats its fifth patient in a phase II clinical trial, assuming that Debiopharm advances Debio 0932 into phase II clinical testing. We currently anticipate that phase II testing could commence in the first half of 2013.

Product Development Programs

We are developing drug candidates designed to treat cancer. Our product development initiatives, described in the chart below, are being pursued using our internal resources or through our collaborations with Genentech and Debiopharm. We believe that our collaborators provide significant additional resources and clinical development expertise to our programs. In addition, under these collaborations our collaborators have agreed to pay us contingent cash payments, assuming the achievement of development and regulatory objectives, and royalties on future product sales, if any.

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Our research and development programs, both internal and under collaboration, are summarized in the following table:

In the chart above, “FDA approval” means that Genentech’s NDA was approved by the FDA for commercialization of Erivedge in the United States. “MAA review” means that Roche has filed an MAA with the EMA, and the EMA has accepted and is currently reviewing the application for potential approval to commercialize Erivedge in Europe. “Phase II” means that Genentech is currently treating human patients in a phase II clinical trial, the primary objective of which is a therapeutic response in the patient population. “Phase I expansion” means that we are currently treating human patients with specific tumor types in an extension of our phase I dose escalation trial, at the maximum tolerated dose from such trial, the principal purpose of which is to evaluate the safety and tolerability of the compound being tested. “Phase Ib” means that Debiopharm is further assessing the safety profile, pharmacokinetics and pharmacodynamics of Debio 0932 at the recommended Phase II dose level, and seeking to make a preliminary assessment of anti-tumor activity in patients with advanced solid tumors. “Phase I” means that we are currently treating human patients in separate phase I clinical trials for CUDC-101, the principal purpose of which is to evaluate the safety and tolerability of the compound being tested. “Development candidate” means that we have selected a single lead candidate for potential future clinical development and are seeking to complete the relevant safety, toxicology, and other studies required to submit an IND application with the FDA seeking to commence a phase I clinical trial based on our testing in several preclinical models of human disease of various compounds from a particular compound class. “Preclinical” means that we are seeking to obtain evidence of therapeutic efficacy and safety in preclinical models of human disease of one or more compounds within a particular class of drug candidates.

Since our inception in 2000, substantially all of our revenues have been derived from collaborations and other agreements with third parties. For the year ended December 31, 2011, Genentech accounted for $14,388,000, or 97%, of our revenue. For the year ended December 31, 2010, Debiopharm and settlement proceeds received from a former collaborator, Micromet, accounted for substantially all of our revenue, as

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follows: Debiopharm, $11,333,000, or 71%, and Micromet, $4,000,000, or 25%. For the year ended December 31, 2009, Genentech and Debiopharm accounted for substantially all of our revenue, as follows: Genentech, $6,229,000, or 73%, and Debiopharm, $2,199,000, or 26%.

Hedgehog Pathway Inhibitor Program (Erivedge)

The Hedgehog pathway is normally active during embryonic development and regulates tissue and organ formation by directly promoting cell division in specific cell types, and by activating other secondary signaling pathways that control the synthesis of growth factors and angiogenic (blood vessel-forming) factors. Malignant activation of the Hedgehog pathway is believed to play a central role in allowing the proliferation and survival of cancer cells, including basal cell carcinoma and medulloblastoma as well as colorectal, ovarian, pancreatic, small cell lung and breast cancers, among others.

Our Hedgehog pathway inhibitor technologies represent our most advanced program and are being developed in various cancer indications under a June 2003 collaboration agreement with Genentech. The lead drug candidate being developed under this program is Erivedge (vismodegib) capsule, a first-in-class orally-administered small molecule Hedgehog pathway inhibitor that is the first and only FDA-approved medicine for adults with advanced forms of basal cell carcinoma that has spread to other parts of the body or that has come back after surgery or that their healthcare provider decides cannot be treated with surgery or radiation. It is not known if Erivedge is safe and effective in children. Genentech and Roche are responsible for the clinical development and commercialization of Erivedge and are currently conducting a phase II clinical trial of GDC-0449 in operable BCC that was initiated in October 2010. In addition, Erivedge is also currently being tested in other cancers in trials under collaborative agreements between Genentech and either third-party investigators or the U.S. National Cancer Institute, or NCI, including in medulloblastoma, sarcoma and glioblastoma multiforme, as well as in pancreatic, small cell lung, gastroesophageal junction, gastric, breast, and prostate cancers, among others. Genentech completed two phase II clinical trials of Erivedge in 2010, including in advanced ovarian cancer and metastatic colorectal cancer. Neither of these studies met their primary endpoints of demonstrating a clinically meaningful extension of progression-free survival and Genentech has determined that it will not pursue further development of Erivedge in these two indications.

Advanced Basal Cell Carcinoma.    In January 2012, Erivedge was approved by the FDA as the first and only FDA-approved medicine for adults with advanced forms of basal cell carcinoma. We earned a $10,000,000 milestone payment from Genentech as a result of the FDA’s approval of Erivedge in this indication and we are also entitled to receive royalties on future sales of the product. During the fourth quarter of 2011, we received a total of $14,000,000 in milestone payments from Genentech relating to the FDA’s acceptance of Genentech’s New Drug Application, or NDA, for Erivedge and the European Medicines Agency’s, or EMA’s, acceptance for review of a Marketing Authorization Application, or MAA for Erivedge, that was submitted by Roche in December 2011. The Genentech NDA and Roche MAA applications were based on positive clinical data from ERIVANCE BCC/SHH4476g, a pivotal phase II study of Erivedge in patients with advanced BCC. We will receive an additional milestone payment if Erivedge also receives EMA marketing authorization, as well as royalties on any future sales in this territory.

In June 2011, Genentech reported positive data from ERIVANCE BCC/SHH4476g. ERIVANCE BCC/SHH4476g is an international, single-arm, multi-center, two-cohort, open-label phase II study that enrolled 104 patients with advanced BCC, including metastatic (33) and locally advanced BCC (71). Locally advanced BCC patients include patients whose lesions were inappropriate for surgery (inoperable, or for whom surgery would result in substantial deformity) and for which radiotherapy was unsuccessful or contraindicated. Metastatic BCC was defined as BCC that had spread to other parts of the body, including the lymph nodes, lung, bones and/or internal organs. The study was conducted at 31 sites in the United States, Australia and Europe. Study participants received 150 mg Erivedge orally, once daily until disease progression or intolerable toxicity. Tumor responses for metastatic BCC were measured by RECIST criteria. For locally advanced BCC, a novel composite endpoint was designed, which included reduction of size of lesions of at least 30% in longest dimension and/or complete resolution of locally advanced BCC ulceration.

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The study met its primary endpoint showing that Erivedge substantially shrank tumors or healed visible lesions, with observed response rates of 43% of patients in the locally advanced BCC cohort and 30% of patients in the metastatic BCC cohort as assessed by an independent review facility. The median duration of response by independent review was 7.6 months for both metastatic and locally advanced BCC patients. The median duration on treatment was 10 and 9.7 months for metastatic BCC and locally advanced BCC patients, respectively.

The most common adverse events observed in the study (observed in greater than 10% of patients) were muscle spasms, alopecia (hair loss), dysgeusia (altered taste sensation), weight loss, fatigue, nausea, diarrhea, decreased appetite, constipation, arthralgias (joint pain), vomiting, and ageusia (loss of taste). In addition, a total of 3 of 10 pre-menopausal women developed amenorrhea, which is the absence of a period, while receiving Erivedge. Treatment emergent grade 3 laboratory abnormalities included hyponatremia (low sodium) in 6 patients, hypokalemia (low potassium) in 2 patients and azotemia (elevation of blood urea nitrogen) in 3 patients. Previous animal studies have indicated that Erivedge is embryotoxic and teratogenic. The FDA-approved labeling thus carries a boxed warning stating that Erivedge can cause fetal harm when administered to pregnant women based on its mechanism of action and recommends the use of contraception during and after treatment.

Operable Basal Cell Carcinoma.    In October 2010, Genentech initiated a phase II clinical trial of Erivedge as a single-agent therapy for patients with operable BCC in which Genentech expects to evaluate Erivedge in approximately 50 patients with operable nodular BCC in a US-based, open label, two-cohort clinical trial. All patients will receive a 150 mg daily oral dose of Erivedge for 12 weeks. The primary outcome measure for the first cohort is the rate of complete histological clearance of target nodular BCC lesions at the time of tumor excision, which may occur up to 12 weeks following initiation of treatment, while the primary outcome measure for the second cohort is the rate of durable complete clearance of target nodular BCC lesions at the time of excision, which may occur up to 36 weeks following initiation of treatment.

Genentech has completed enrollment and data evaluation for patients treated in the first cohort of this study, and has submitted data from this cohort for presentation at a medical conference during the first half of 2012. Genentech has informed us that further study and analysis of Erivedge in operable BCC is required to determine a potential future development plan, including completing ongoing patient enrollment and treatment in the second cohort. We currently anticipate that the study will be completed during early 2013.

Other Erivedge Clinical Trials.    In addition to the ongoing clinical trials that Genentech and Roche are conducting, Genentech and the NCI entered into a collaborative relationship that allows the NCI to study Erivedge in additional potential cancer indications. Third party investigators are conducting several additional clinical trials with Erivedge under this collaboration, including in medulloblastoma, sarcoma and glioblastoma multiforme as well as in pancreatic, small cell lung, gastroesophageal junction/gastric, breast, and prostate cancers, among others. Furthermore, an investigator-sponsored study evaluating Erivedge in patients with basal cell nevus (Gorlin) syndrome has been initiated.

Interim data from an investigator-sponsored study in basal cell nevus syndrome, or BCNS, was presented in April 2011 at the American Association for Cancer Research 2011 annual meeting. This phase II double blind, randomized placebo-controlled, two arm multicenter clinical study of Erivedge enrolled 41 BCNS patients from September 2009 to January 2011. This study is designed to assess the safety and efficacy of a 150 mg dose of daily oral Erivedge versus a placebo. A Data Safety Monitoring Board, or DSMB, tasked with reviewing the unblinded results from an interim analysis of 29 patients who completed an average of six months of drug treatment, subsequently recommended to end the placebo arm of the trial due to statistically significant differences between the two groups, in order for all of the patients enrolled in the trial to receive Erivedge treatment. The DSMB’s analysis revealed that Erivedge reduced the rate of new BCCs from an average of 1.74 BCCs per month in the placebo group to 0.07 in the Erivedge group (p<0.0001). Erivedge also reduced the size of existing BCCs (-24 cm vs. 3 cm placebo, cumulative diameter, p=0.006). Observations related to Erivedge’s safety were similar to what has been reported in previous clinical studies, including grade 1-2 taste loss, muscle cramps, hair loss and weight loss when compared to placebo were common. There were two grade 3-4 adverse events observed, including one grade 3 muscle cramp and one grade 4 depression. Overall, 28% of patients taking Erivedge discontinued participation due to adverse events.

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Under the terms of our June 2003 collaborative research, development and license agreement with Genentech, we granted Genentech an exclusive, global, royalty-bearing license, with the right to sublicense, to make, use, sell and import small molecule and antibody Hedgehog pathway inhibitors for human therapeutic applications, including cancer therapy. We were responsible for performing certain funded preclinical research activities through December 2006. In November 2008, Genentech granted a sublicense to Roche for non-U.S. rights to Erivedge. Roche received this sublicense pursuant to an agreement between Genentech and Roche under which Genentech granted Roche an option to obtain a license to commercialize certain Genentech products in non-U.S. markets. In February 2010, we announced that Chugai Pharmaceutical Co., Ltd. had exercised its right of first refusal for the development and commercialization in Japan of Erivedge under an existing agreement with Roche.

Genentech and Roche have primary responsibility for worldwide clinical development, regulatory affairs, manufacturing and supply, formulation and sales and marketing. We are eligible to receive up to $115,000,000 in contingent cash payments for the development of Erivedge or another small molecule, assuming the successful achievement by Genentech and Roche of specified clinical development and regulatory objectives. We have received $42,000,000 of this amount including the $10,000,000 payment that we earned in January 2012. We are also eligible to receive royalties on sales of any Hedgehog pathway inhibitor products that are successfully commercialized by Genentech and Roche. For Erivedge, we are entitled to a mid-to-high single digit royalty, which escalates within this range with increasing product sales. In certain specified circumstances, the royalty rate applicable to Erivedge may be decreased to a low-to-mid single digit royalty.

Unless terminated earlier, the agreement will expire six months after the later of the expiration of Genentech’s obligation to pay royalties to us under the agreement or such time as no activities have occurred under the agreement for a period of twelve months. The agreement may be terminated earlier by either party for cause upon sixty days prior written notice. In addition, Genentech may terminate the agreement, either in whole or in part, without cause, upon six months prior written notice. In the event of any termination where specific license grants survive, we will continue to have the right to receive clinical development and regulatory approval milestones and royalties on product sales for such licensed compound, if any. If we terminate the agreement for cause or Genentech terminates the agreement without cause, all licenses granted to Genentech automatically terminate and revert to us. In addition, Genentech has agreed that it will no longer conduct any development or commercialization activities on any compounds identified during the course of the agreement for so long as such compounds continue to be covered by valid patent claims.

As a result of our licensing agreements with various universities, we are obligated to make payments to these university licensors totaling 5% of certain milestone and any royalty payments we receive from Genentech. From the inception of our Genentech collaboration through December 31, 2011, we have incurred expenses of $1,600,000 related to such payments. We incurred expenses of $500,000 upon receipt of the $10,000,000 payment from Genentech for FDA approval of Erivedge that occurred in January 2012, and we will also be obligated to pay a total of 5% of any royalties we receive upon the sale of Erivedge to these sublicensors.

Our Proprietary Network-Targeted Cancer Programs

Over the past several years, targeted cancer drugs have been considered by scientists and clinicians to be among the most promising cancer treatments for obtaining a therapeutic effect with less toxicity when compared with traditional chemotherapy, which, in addition to attacking cancerous cells, also tends to attack a broad range of healthy cells. A large body of published data shows cancers to have multiple, intersecting signaling pathways, or networks, that support survival, growth, and invasion. Targeting only one or two of these pathways has generally only led to modest improvements to existing standards-of-care and most cancer patients with solid tumors do not respond in a clinically meaningful manner. We believe that targeting the correct combination of critical signaling pathways within the network of cancer cell signaling pathways could provide a major improvement in outcomes for cancer patients.

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We are utilizing our medicinal chemistry and biological expertise to develop a series of proprietary network-targeted cancer drug programs. In these programs we are focusing on the development of proprietary, small molecule single-agent drug candidates that target one or more molecular components within the network of signaling pathways associated with certain cancers. Each proprietary compound is being designed to inhibit one or more validated cancer targets, including, among others, EGFR, Her2, Bcr-Abl tyrosine kinase and phosphatidylinositol-3-kinase, or PI3k, in combination with inhibition of HDAC, which is a validated non-kinase cancer target. We are also seeking to develop proprietary, differentiated, single-agent, single-target drug candidates for cancer indications, as exemplified by Debio 0932. This molecule was discovered by us and licensed in 2009 to Debiopharm for further development.

HDAC inhibition is a core component in a majority of our network-targeted inhibitors. We believe that HDAC is a very promising non-kinase target for cancer therapy, particularly when combined with simultaneous inhibition of certain other targets. There is substantial preclinical evidence of synergistic induction of cancer cell death when HDAC inhibitors are combined with a diverse range of other targeted therapies or standard chemotherapeutic agents, demonstrating that HDAC inhibition may be more broadly effective in the treatment of cancer when integrated with other inhibitory activities. Currently, there are two FDA-approved HDAC inhibitors and several other HDAC-targeted drug candidates in clinical trials for cancer, many in combination with other agents or modalities.

We have filed a number of patent applications including a broad omnibus patent application that covers the drug design concept that is the basis for our network-targeted cancer programs, as well as numerous species filings relating to specific classes of compounds which we believe will constitute novel compositions from a patentability standpoint. We expect that we will continue to file additional patent applications covering new compositions in the future.

CUDC-101.    CUDC-101 is the first compound we have selected as a drug candidate from our portfolio of network-targeted cancer programs. CUDC-101 is designed as a first-in-class single-agent therapeutic to simultaneously inhibit HDAC, EGFR and Her2. In preclinical studies, CUDC-101 demonstrated the potential to inhibit all three molecular targets resulting in the potent killing of a wide range of cancer cell lines that are representative of a variety of human cancer types, many of which have demonstrated resistance to various approved targeted agents.

Our data suggest that CUDC-101’s mechanism of action involves the increased sensitization of cancer cells to EGFR and Her2 inhibition through HDAC inhibition. CUDC-101 simultaneously inhibits both EGFR and Her2 at the receptor level while blocking downstream HDAC inhibition within the cancer cells. Despite the existence of other molecules that seek to inhibit multiple targets, CUDC-101 is unique in its choice of targets which we believe enables a synergistic attack on multiple nodes or points in the overall pathway network that are used by tumors to survive, grow, and invade surrounding tissue. Utilizing the same targeted strategy with other currently available drugs would require combining two or three separate agents, which typically have mismatched dosing schedules and may display additive dose limiting toxicities. In contrast, we believe that CUDC-101, as a single small molecule, has the potential to act in the same cancer cells at the same time with fewer toxic side effects and thus potentially represents an important advance in targeted agent cancer therapy.

In April 2010, we completed a dose escalation phase I clinical trial of this molecule. This phase I trial was designed as an open-label, dose escalation study of CUDC-101 in patients with advanced, refractory solid tumors in which the primary objectives were to evaluate the safety and tolerability of escalating doses of CUDC-101 and to establish the maximum tolerated dose and dose limiting toxicities. Secondary objectives included the assessment of efficacy. The study was conducted at two clinical sites within the United States and enrolled 25 patients across several dose-escalating cohorts. CUDC-101 demonstrated promising evidence of antitumor activity in this study at doses ranging from 150 milligrams per meter² to 275 milligrams per meter², including one confirmed partial response that was achieved in a gastric cancer patient at 275 milligrams per meter² and a stable disease of greater than three months observed in a refractory breast cancer patient at 150 milligrams per meter². Two head and neck cancer patients, including one patient with salivary gland adenocarcinoma and one

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patient with squamous cell carcinoma of the tongue, exhibited anti-tumor activity with a decrease of greater than 20% in their respective target lesions. We concluded dosing in this phase I dose escalation study in March 2010 and determined that 275 milligrams per meter² represented the maximum tolerated dose of CUDC-101. CUDC-101 also exhibited dose-proportionate increases in pharmacological parameters and what we believe to be a favorable safety profile. The most frequent adverse events were mild to moderate and included fatigue, vomiting, dyspnea (shortness of breath), pyrexia (fever), and dry skin.

In October 2011, we completed a phase Ib expansion trial to test CUDC-101 in 46 patients with specific tumor types, including breast, gastric, head and neck, liver and non-small cell lung cancers. The phase Ib expansion trial was designed as an open-label study in which these patients were treated with CUDC-101 at the maximum tolerated dose of 275 milligrams per meter² at seven study centers in the United States. The primary objectives of this study are to compare the safety and tolerability of CUDC-101 in subjects with specific advanced solid tumors when the drug is administered either on a five days per week schedule (one week on/one week off) or on a three days per week schedule (three weeks on/one week off). The secondary study objectives include evaluation of the pharmacokinetics and pharmacodynamic biomarkers following CUDC-101 administration and to assess the efficacy of CUDC-101 in this patient population. The safety profile observed to-date for both dosing schedules appears to be consistent with that observed in the phase I dose escalation study. In addition, we have observed stable disease in several patients in this study. Most notably, we have observed stable disease lasting more than 14 weeks in four patients: two patients with liver cancer and one patient each with head and neck and gastric cancer.

We presented the phase I dose escalation study data at the 22nd EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics, and anticipate that we will present data from the phase I expansion study at a medical conference during the first half of 2012.

During the third quarter of 2011, we treated the first patient in a phase I clinical trial of CUDC-101 in locally advanced head and neck cancer patients whose cancer is human papilloma virus, or HPV, negative. The primary objectives of this study are to evaluate the safety and tolerability of CUDC-101 when administered in combination with the current standard-of-care of cisplatin, a chemotherapeutic drug, and radiation. Upon determination of the maximum tolerated dose and assuming the otherwise successful completion of the phase I trial, we intend to conduct a randomized phase II two-arm clinical trial in which head and neck cancer patients will receive cisplatin and radiation plus or minus CUDC-101. The phase II study would seek to evaluate whether the addition of CUDC-101 can improve the efficacy and durability of cisplatin and radiation therapy in this patient population.

We selected head and neck cancer as our first indication for potential phase II testing of CUDC-101 for several reasons. First, CUDC-101 demonstrated biological activity in two patients with head and neck cancer in the phase I dose escalation study, including a mixed response in a head and neck cancer patient at 150 mg/m2 dose level and a tumor reduction of over 20% after just four weeks of study drug administration in a separate head and neck cancer patient at the 275 mg/m2 dosing level. Second, our research team generated strong in vitro and in vivo preclinical data in head and neck cancer, exemplified by data in seven head and neck cancer cell lines that includes some of the highest potency observed of the cell lines in which CUDC-101 was tested. Lastly, we believe that this internal data is supported by published literature demonstrating that both EGFR and Her2 are often implicated in head and neck cancers.

There are approximately 30,000 newly diagnosed advanced head and neck cancer patients in the U.S. annually, of which approximately 60-70% have tumors that are HPV negative. It has been shown that head and neck tumors overexpress EGFR in 80-100% of cases, and also overexpress Her2 in 20-40% of cases. CUDC-101 is designed to inhibit both EGFR and Her2, potentially providing an added benefit for patients. CUDC-101 is also designed to target HDAC, which has been demonstrated to provide synergistic effects when combined with radiation therapy. We believe that CUDC-101’s current intravenous formulation is suitable for this patient population because patients are required to receive daily radiation treatment for several weeks at their respective clinical centers.

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We are also working on an oral formulation of CUDC-101, which we believe has the potential to make CUDC-101 more competitive in certain cancers such as non-small cell lung cancer where patients are generally on therapy for several months and there are competing commercially available molecules that are orally administered. Pending the successful completion of ongoing formulation and preclinical development work, we intend to begin a phase I study of an oral formulation of CUDC-101 during 2012.

CUDC-907.    In January 2011, we selected development candidate CUDC-907, an orally bioavailable, network-targeted small molecule that is designed to inhibit HDAC and phosphatidylinositol-3-kinase, or PI3K.

Our scientists developed CUDC-907 based on published and internally generated data demonstrating that HDAC and PI3K inhibitors have synergistic interaction against cancer cells. In vitro mechanism of action studies demonstrate that CUDC-907 is able to inhibit Class I PI3Ks and upregulate molecules involved in cancer cell death. CUDC-907 has also demonstrated the ability to suppress multiple nodes of other survival pathways as a result of the epigenetic modification resulting from the inhibition of its non-kinase HDAC target. By contrast, we believe that the single-target PI3K inhibitors currently in clinical development only target the primary PI3K survival pathway and have been reported to have only limited effects on tumors with disregulation of other signaling pathways.

CUDC-907 displays high exposure and long half-life in tumor tissue after IV administration and is orally bioavailable in animals. CUDC-907 exhibits anti-proliferation activity against a broad range of cancer cell types in in vitro studies, including cell lines that exhibit reduced sensitivity to single-target PI3K inhibitors. CUDC-907’s anti-proliferation activity has been demonstrated to be up to 100-fold more potent than that of two leading PI3K inhibitors in development. CUDC-907 also inhibits tumor growth in preclinical xenograft models of hematology cancers and solid tumors with K-RAS mutations that exhibit reduced sensitivity to PI3K inhibitors, indicating that this compound may have broader activity than other leading PI3K inhibitors currently in clinical development. This compound also displays a favorable safety profile in our early safety evaluation. We believe that its synergistic mechanism of cancer signaling network disruption, efficacy in a number of preclinical xenograft models and favorable safety profile could provide rationale for further clinical development.

In November 2011, we entered into an agreement under which The Leukemia & Lymphoma Society, or LLS, will provide a portion of the funding for our ongoing development of CUDC-907 for patients with B-cell lymphoma and multiple myeloma if we succeed in advancing CUDC-907 into a clinical trial. We are currently conducting preclinical studies of CUDC-907 which are required to file an IND. We expect to file the IND and then will start patient enrollment in a phase Ia dose escalation clinical trial in the second half of 2012 in patients with B-cell lymphoma and multiple myeloma.

Other Network-Targeted Cancer Programs.    In addition to our development-stage programs, we continue to progress additional proprietary research programs and expect that we will select additional small molecule inhibitors from our preclinical portfolio in the future.

Debio 0932.    Heat shock protein 90, or Hsp90, is a member of a class of proteins called molecular chaperones that play a fundamental role in the folding, stabilization and degradation of other cellular proteins, or clients, under normal or stressful conditions. Hsp90, in particular, has become an attractive therapeutic target for the treatment of cancer because a majority of its client proteins are involved in cellular signaling transduction and have been identified as potential contributors to various aspects of cancer cell growth and survival. Inhibitors of Hsp90 activity may be of therapeutic value if they can prevent Hsp90 proteins from protecting the particular client proteins involved in cancer and allow them to be degraded, thereby inducing cancer cell death. In our preclinical studies, our lead candidate Debio 0932 demonstrated potent efficacy across a broad range of cancers in preclinical cancer models and exhibited promising pharmacological features in preclinical testing, particularly its high oral bioavailability, high tumor penetration and extended tumor retention. Tumor regression was also observed after treatment of Debio 0932 in mouse xenograft models of acute myelogenous leukemia, breast, non-small cell lung, gastric and colon cancers as well as in glioblastoma brain cancers. In our preclinical testing, the compound also demonstrated an ability to effectively cross the blood brain barrier and extend survival in preclinical intracranial glioblastoma and brain metastasis models.

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In August 2009, we granted a worldwide, exclusive royalty-bearing license to develop, manufacture, market and sell our Hsp90 inhibitor technology, including our preclinical development candidate, Debio 0932, to Debiopharm. Debiopharm has assumed all future development responsibility for Debio 0932 and Debiopharm or a Debiopharm licensee will incur all future costs related to the development, registration and commercialization of products under the agreement.

In April 2010, Debiopharm treated the first patient in a phase I clinical trial to evaluate the safety of Debio 0932 in patients suffering from advanced solid tumors. In 2011, Debiopharm successfully advanced Debio 0932 through the dose escalation portion of the phase I study. Debio 0932 was generally well tolerated, with no evidence of ocular or liver toxicity, both of which had been observed in previous clinical testing of certain other Hsp90 inhibitors. Debio 0932 also showed promising signs of efficacy in patients with advanced solid tumors in this study. Debiopharm has indicated that it expects to present phase I data from this phase I study at a medical conference during the first half of 2012.

Debiopharm advanced Debio 0932 into the phase Ib expansion portion of the study in the beginning of 2012. Debiopharm expects to treat approximately 30 patients in this phase Ib study, with the primary objectives of further assessing the safety profile, pharmacokinetics and pharmacodynamics of Debio 0932 at the recommended dose level of 1000mg daily that was established in the dose escalation portion of the Phase I clinical trial, and making a preliminary assessment of anti-tumor activity in patients with advanced solid tumors, including patients with non-small cell lung cancer.

Debiopharm has also indicated that it expects to initiate a combination Phase I/II study in non-small cell lung cancer patients in the second quarter of 2012. We are eligible for our next milestone payment under our license agreement if and when Debiopharm treats its fifth patient in a phase II clinical trial, assuming that Debiopharm advances Debio 0932 into phase II clinical testing. We currently anticipate that phase II testing could commence in the first half of 2013.

Debiopharm paid us an up-front license fee of $2,000,000 pursuant to the agreement. In addition, during 2010, we earned $11,000,000 in contingent payments upon Debiopharm’s successful achievement of clinical objectives, including the approval from French regulatory authorities of Debiopharm’s clinical trial application, or CTA, to begin phase I clinical trials and the treatment of the fifth patient in this trial. We are eligible to receive up to an additional $77,000,000 if specified clinical development and regulatory approval objectives are met. We are also eligible to receive royalties if any products under the license agreement are successfully developed and commercialized. For net sales of Debio 0932 that are made directly by Debiopharm, we are entitled to a high single digit to low double digit royalty, which escalates within this range with increasing product sales. In certain specified circumstances, the royalty rate applicable to Debio 0932 may be reduced. We believe that it is more likely that Debiopharm will sublicense Debio 0932 following its further development, and in this case we are entitled to a share of royalties that Debiopharm receives from such sublicensee.

The agreement is effective as of August 5, 2009, and unless terminated earlier will expire, on a country-by-country basis, on the later of (i) the expiration of the last-to-expire valid claim of the Curis patents and joint patents relating to the products, and (ii) the 10^th anniversary of the first commercial sale of the product in such country. Debiopharm may terminate the agreement prior to its expiration at any time for any scientific, technical, administrative or commercial reasons upon 90 days’ prior written notice to us. If Debiopharm is permanently enjoined from exercising its license under the agreement pursuant to a patent infringement action brought by a third party, or if neither Debiopharm nor we undertake the defense or settlement of a third party suit alleging infringement within the six-month period after notice of such suit, then Debiopharm may terminate the agreement in the country where such suit was filed upon thirty days’ prior written notice to us. If Debiopharm does not correct a failure to use reasonable commercial efforts as set forth in the agreement, we may terminate the agreement on thirty days’ written notice to Debiopharm unless Debiopharm cures such failure before the end of such thirty day period. Either party may terminate the agreement prior to its expiration subject to certain conditions, upon ninety days’ (or forty-five days’ in the case of failure to make payment of amounts due under

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the agreement) prior written notice to the other party in the event of the material breach of any term or condition of the agreement by the other party, unless the breaching party has cured such breach by the end of the applicable cure period; and immediately upon written notice to the other party if the other party or its affiliate directly, or through assistance granted to a third party, challenges, whether as a claim, a cross-claim, counterclaim, or defense, the validity or enforceability of any of such party’s patents before any court, arbitrator, or other tribunal or administrative agency in any jurisdiction.

Corporate Information

We were organized as a Delaware corporation in February 2000. We began our operations in July 2000 upon the completion of the merger of Creative BioMolecules, Inc., Ontogeny, Inc. and Reprogenesis, Inc. Our principal executive office is located at 4 Maguire Road, Lexington, MA 02421 and our telephone number is (617) 503-6500.

Curis™ is our trademark and Erivedge is a trademark of Genentech. This annual report on Form 10-K may also contain trademarks and trade names of others.

Website Access to Reports

We maintain a website with the address www.curis.com. We are not including the information contained in our website as part of, or incorporating it by reference into, this annual report on Form 10-K. Our website address is included in this annual report on Form 10-K as an inactive textual reference only. We make available free of charge through our website our annual reports on Form 10-K, our quarterly reports on Form 10-Q, current reports on Form 8-K and any such amendments to those reports as soon as reasonably practicable after we electronically file such material with, or furnish such material to, the Securities and Exchange Commission. The Securities and Exchange Commission maintains a website, www.sec.gov, that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC. The public may read and copy any materials we file with the Securities and Exchange Commission at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. In addition, we provide paper copies of our filings free of charge upon request. The public may obtain information on the operation of the public reference room by calling 1-800-SEC-0330. We also make available on our website our corporate governance guidelines, the charters for our audit committee, compensation committee and nominating and corporate governance committee, and our code of business conduct and ethics, and such information is available in print to any stockholder of Curis who requests it.

Intellectual Property

Our policy is to obtain and enforce the patents and proprietary technology rights that are key to our business. We intend to continue to file U.S. and foreign patent applications to protect technology, inventions and improvements that are considered important to the development of our business. We will be able to protect our proprietary technologies from unauthorized use by third parties only to the extent that our proprietary rights are covered by valid and enforceable patents or are effectively maintained as trade secrets.

In the U.S., we have 83 issued or allowed patents expiring on various dates between 2013 and 2028 as well as numerous pending patent applications. We have foreign counterpart patent filings for most of our U.S. issued patents and patent applications. These patents and patent applications are directed to various inventions including compositions of matter, methods of making and using these compositions for multiple applications, methods for drug screening and discovery, developmental biological processes, and patents which relate to our proprietary technologies.

Hedgehog Pathway.    We have 72 issued U.S. patents or allowed U.S. applications expiring on various dates between 2013 and 2028, which relate to the Hedgehog pathway. Our patents and patent applications cover proteins, nucleic acids, antibodies, and certain small molecule agonists and inhibitors of the Hedgehog pathway,

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drug screening and discovery methods, methods of protein manufacturing, as well as methods of using the aforementioned proteins, nucleic acids, antibodies or small molecules to activate or inhibit the Hedgehog pathway for a variety of therapeutic indications or diagnostic uses. In addition, we have filed foreign patent applications corresponding to many of the aforementioned U.S. filings that could provide additional patent protection for products that activate or inhibit the Hedgehog pathway.

Our academic and research institution collaborators have certain rights to publish data and information regarding their discoveries to which we have rights. While we believe that the prepublication access to the data developed by our collaborators pursuant to our collaboration agreements will be sufficient to permit us to apply for patent protection in the areas in which we are interested in pursuing further research, there is considerable pressure on such institutions to rapidly publish discoveries arising from their efforts. This may affect our ability to obtain patent protection in the areas in which we may have an interest. In addition, these collaboration agreements typically contain provisions that provide us with, at a minimum, an option to license the institution’s rights to intellectual property arising from the collaboration.

Network-Targeted Cancer Drug Development Platform.    We have eight issued or allowed U.S. patents which expire in 2027 and 2028 and several U.S. provisional patent applications and U.S. and foreign utility patent applications directed to our targeted inhibitor classes of novel small molecules, as well as U.S. and foreign patent applications which generically claim the platform concept itself. Our patents and patent applications cover compositions of matter, methods of manufacturing these molecules, formulations, and methods of using these molecules to treat a variety of therapeutic indications. We intend to continue to file additional U.S. and foreign applications as the programs progress.

We are party to various license agreements that give us rights to commercialize various technologies, particularly our Hedgehog pathway technologies, and to use technologies in our research and development processes. The consideration payable in exchange for these licenses includes up-front fees, issuances of shares of common stock, annual royalties, milestone payments and royalties on net sales by our sub-licensees and us. The licensors may terminate these agreements if we fail to meet certain diligence requirements, fail to make payments or otherwise commit a material breach that is not cured after notice.

In addition, we depend upon trade secrets, know-how and continuing technological advances to develop and maintain our competitive position. To maintain the confidentiality of trade secrets and proprietary information, we require our employees, scientific advisors, consultants and collaborators, upon commencement of a relationship with us, to execute confidentiality agreements and, in the case of parties other than our research and development collaborators, to agree to assign their inventions to us. These agreements are designed to protect our proprietary information and to grant us ownership of technologies that are developed in connection with their

Research and Development Program

We have a research group that seeks to identify and develop new therapeutic products and applications thereof for our existing proprietary portfolio and seeks to identify novel compounds able to modulate additional signaling pathways that may have therapeutic potential. As of December 31, 2011, our research and development group consists of 25 employees, consisting of molecular biologists, cell biologists, chemists, pharmacologists and other scientific disciplines. We have also engaged approximately 16 medicinal chemists on a contract basis at a contract research organization in China.

The estimated amounts spent on company-sponsored research and development activities for the years ended December 31, 2011, 2010 and 2009 were $13,693,000, $11,373,000 and $9,933,000, respectively. We had no collaborator-sponsored research and development expense for the years ended December 31, 2011, 2010 and 2009 as all research funding under collaborations concluded in 2008.

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Regulatory Matters

FDA Requirements for New Drug Compounds

Numerous governmental authorities in the U.S. and other countries extensively regulate, among other things, the research, testing, manufacture, import and export and marketing of drug products. In the U.S., drugs are subject to rigorous regulation by the FDA. The Federal Food, Drug, and Cosmetic Act, and other federal and state statutes and regulations, govern, among other things, the research, development, testing, manufacture, storage, recordkeeping, labeling, promotion, sampling and marketing and distribution of pharmaceutical products. Failure to comply with applicable regulatory requirements may subject a company to a variety of administrative or judicially imposed sanctions. These sanctions could include, among other things, the FDA’s refusal to approve pending applications, withdrawal of approvals, clinical holds, warning letters, product recalls, product seizures, total or partial suspension of our operations, injunctions, fines, civil penalties or criminal prosecution.

The steps ordinarily required before a new pharmaceutical product may be marketed in the U.S. include preclinical laboratory tests, animal tests and formulation studies under the FDA’s good laboratory practice, or GLP, regulations; the submission to the FDA of an investigational new drug application, or an IND, which must become effective before testing in humans, or clinical testing, may commence; approval by an independent institutional review board, or IRB, at each clinical site before each trial may be initiated; adequate and well-controlled clinical trials to establish the safety and effectiveness of the drug for each indication for which FDA approval is sought; submission to the FDA of a new drug application, or NDA, seeking approval to market the drug product; satisfactory completion of an FDA advisory committee review, if applicable; satisfactory completion of an FDA inspection of the manufacturing facility or facilities at which the product is produced to assess compliance with current good manufacturing practice, or cGMP, requirements; and FDA review and approval of the NDA. Satisfaction of FDA pre-market approval requirements typically takes years, and the actual time required may vary substantially based upon the type, complexity and novelty of the product or disease. Success in early stage clinical trials does not assure success in later stage clinical trials. Data obtained from clinical activities is not always conclusive and may be susceptible to varying interpretations that could delay, limit or prevent regulatory approval. Even if a product receives regulatory approval, later discovery of previously unknown problems with a product, including new safety risks, may result in restrictions on the product or even complete withdrawal of the product from the market.

Preclinical tests include laboratory evaluation of product chemistry and formulation, as well as animal trials to assess the potential safety and efficacy of the product. The conduct of the preclinical tests and formulation of compounds for testing must comply with federal regulations and requirements, including the FDA’s GLP regulations. Preclinical testing is highly uncertain and may not be completed successfully within any specified time period, if at all. Further, the successful completion of preclinical trials does not assure success in human clinical trials. The results of preclinical testing are submitted to the FDA as part of an IND application, together with manufacturing information, analytical and stability data of the drug formulation, and other information. The IND application must become effective before clinical trials can begin in the United States. An IND application becomes effective 30 days after receipt by the FDA unless before that time the FDA places a clinical hold on the trials. In that case, the IND application sponsor and the FDA must resolve any outstanding FDA concerns or questions before clinical trials can proceed. If these concerns or questions are unresolved, the FDA may not allow the clinical trials to commence.

Clinical trials involve the administration of the investigational drug to healthy human volunteers or patients under the supervision of a qualified investigator. Clinical trials must be conducted in compliance with federal regulations and requirements, including good clinical practices, under protocols detailing, among other things, the objectives of the trial, the parameters to be used in assessing safety and the effectiveness criteria to be evaluated. Each protocol involving testing on U.S. subjects must be submitted to the FDA as part of the IND application. In addition, an IRB at each institution participating in the clinical trial must review and approve the plan for any clinical trial before it commences at that institution, and the IRB must conduct continuing review. The IRB must review and approve, among other things, the study protocol and informed consent information to be provided to study subjects. An IRB must operate in compliance with FDA regulations.

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Clinical trials to support NDAs for marketing approval are typically conducted in three sequential phases, but the phases may overlap or be combined. In phase I, the initial introduction of the drug into human subjects, the drug is tested to assess metabolism, pharmacokinetics and pharmacological actions and safety, including side effects associated with increasing doses and, if possible, early evidence of effectiveness. Phase II usually involves trials in a limited patient population, to determine dosage tolerance and optimum dosage, identify possible adverse effects and safety risks, and provide preliminary support for the efficacy of the drug in the indication being studied. If a compound demonstrates evidence of effectiveness and an acceptable safety profile in phase II evaluations, phase III trials may be undertaken to further evaluate clinical efficacy and to further test for safety within an expanded patient population, typically at geographically dispersed clinical trial sites to establish the overall benefit-risk relationship of the drug and to provide adequate information for the labeling of the drug. Phase I, phase II or phase III testing of any drug candidates may not be completed successfully within any specified time period, if at all. The FDA closely monitors the progress of each of the three phases of clinical trials that are conducted in the U.S. The FDA may, at its discretion, reevaluate, alter, suspend or terminate the testing based upon the data accumulated to that point and the FDA’s assessment of the risk/benefit ratio to the subject. The FDA, an IRB, or a clinical trial sponsor may suspend or terminate clinical trials at any time for various reasons, including a finding that the subjects or patients are being exposed to an unacceptable health risk. The FDA can also request that additional clinical trials be conducted as a condition to product approval. Finally, sponsors are required to publicly disseminate information about ongoing and completed clinical trials on a government website administered by the National Institutes of Health, or NIH, and are subject to civil money penalties and other civil and criminal sanctions for failing to meet these obligations.

After successful completion of the required clinical testing, generally an NDA is prepared and submitted to the FDA. FDA approval of the NDA is required before marketing of the product may begin in the United States. The NDA must include the results of extensive preclinical and clinical testing, a compilation of data relating to the product’s pharmacology, chemistry, manufacture, and controls, and proposed labeling, among other things,. In most cases, a substantial user fee must accompany the NDA. The FDA conducts a preliminary review of all NDAs within the first 60 days after submission before accepting them for filing to determine whether they are sufficiently complete to permit substantive review. The FDA may request additional information rather than accept an NDA for filing. In this event, the application must be resubmitted with the additional information. The resubmitted application is also subject to review before the FDA accepts it for filing. Once the submission is accepted for filing, the FDA begins an in-depth substantive review. The FDA has agreed to specified performance goals regarding the timing of its review of NDAs, although the FDA does not always meet these goals. The FDA may also refer applications for novel drugs or products that present difficult questions of safety or efficacy to an advisory committee, typically a panel that includes clinicians and other experts, for review, evaluation and a recommendation as to whether the application should be approved. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions.

Before approving an NDA, the FDA typically will inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. In addition, before approving an NDA, the FDA will typically inspect one or more clinical sites to assure compliance with GCP and integrity of the clinical data submitted.

If the FDA’s evaluation of the NDA and inspection of the manufacturing facilities are favorable, the FDA may issue an approval letter, or, in some cases, a complete response letter. A complete response letter generally contains a statement of specific conditions that must be met in order to secure final approval of the NDA. If and when those conditions have been met to the FDA’s satisfaction, the FDA will typically issue an approval letter. An approval letter authorizes commercial marketing of the drug with specific prescribing information for specific indications. As a condition of NDA approval, the FDA may require post-approval testing, including phase IV trials, and surveillance to monitor the drug’s safety or efficacy and may impose other conditions, including labeling restrictions and restrictions on distribution and use of the drug, which can materially impact the potential market and profitability of the drug. Once granted, product approvals may be withdrawn if compliance with regulatory standards is not maintained or problems are identified following initial marketing.

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Once the NDA is approved, a product will be subject to certain post-approval requirements, including requirements for adverse event reporting, submission of periodic reports, and drug sampling and distribution requirements. If new safety issues arise after approval, the FDA may require the company to conduct additional post-market studies to assess the risk, change the labeling to address the risk, or impose distribution and use restrictions under a Risk Evaluation and Mitigation Strategy, or REMS. Additionally, the FDA strictly regulates the promotional claims that may be made about prescription drug products. In particular, a drug may not be promoted for uses that are not approved by the FDA as reflected in the drug’s approved labeling. Moreover, the Department of Justice can bring civil or criminal actions against companies that promote drugs for unapproved uses, based on the Federal Food, Drug, and Cosmetic Act, the False Claims Act and other federal laws governing reimbursement for drugs under the Medicare and Medicaid laws. Monetary penalties in such cases have often been in excess of $100 million and in some cases have exceeded $1 billion. In addition, the FDA requires substantiation of any claims of superiority of one product over another including, in many cases, requirements that such claims be proven by adequate and well-controlled head-to-head clinical trials. After approval, some types of changes to the approved product, such as adding new indications, manufacturing changes and additional labeling claims, are subject to FDA review and approval of a new NDA or NDA supplement before the change can be implemented. Manufacturing operations must continue to conform to cGMPs after approval. Drug manufacturers are required to register their facilities with the FDA and are subject to periodic unannounced inspections by the FDA to assess compliance with cGMPs. Accordingly, manufacturers must continue to expend time, money and effort in the area of production and quality control to maintain compliance with cGMPs and other aspects of regulatory compliance.

If the FDA’s evaluation of the NDA submission or manufacturing facilities is not favorable, the FDA may refuse to approve the NDA or issue a complete response letter. The complete response letter outlines the deficiencies in the submission and may require additional testing or information in order for the FDA to reconsider the application. Even with submission of this additional information, the FDA ultimately may decide that the application does not satisfy the regulatory criteria for approval. With limited exceptions, the FDA may withhold approval of a NDA regardless of prior advice it may have provided or commitments it may have made to the sponsor.

Foreign Regulation of New Drug Compounds

Approval of a drug product by comparable regulatory authorities will be necessary in foreign countries prior to the commencement of marketing of the product in those countries, whether or not FDA approval has been obtained. While clinical data generated in the U.S. may be accepted in many foreign jurisdictions in lieu of early stage clinical trials (phase I), the approval procedure varies among countries and can involve requirements for additional testing equivalent to phases II and III. The time required may differ from that required for FDA approval and may be longer than that required to obtain FDA approval. There can be substantial delays in obtaining required approvals from foreign regulatory authorities after the relevant applications are filed.

In Europe, marketing authorizations may be submitted under a centralized or decentralized procedure. The centralized procedure is mandatory for the approval of biotechnology products and many pharmaceutical products, and provides for the grant of a single marketing authorization, which is valid in all European Union member states. The decentralized procedure is a mutual recognition procedure that is available at the request of the applicant for medicinal products that are not subject to the centralized procedure.

Hazardous Materials

Our research and development processes involve the controlled use of hazardous materials, chemicals and radioactive materials and produce waste products. We are subject to federal, state and local laws and regulations governing the use, manufacture, storage, handling and disposal of hazardous materials and waste products.

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Competition

Our drug candidates, if approved, will compete with existing and new products being developed by others for treatment of the same indications. Competition in the development of human therapeutics and, in particular, human therapeutics that target signaling pathways to treat cancers, is intense. Our competitors include large pharmaceutical and biopharmaceutical companies, as well as specialized biotechnology firms, that are developing cancer therapies in the same indications as we are.

Hedgehog Pathway Inhibitor Program.    We are aware of several biotechnology and pharmaceutical companies that have drug development programs relating to compounds that modulate the Hedgehog pathway. We believe that there are currently at least five other companies that have progressed Hedgehog pathway inhibitors into clinical development: Infinity Pharmaceuticals, Inc.; Exelixis, Inc. (in co-development with the Bristol-Myers Squibb Company); Pfizer Inc.; Novartis International AG; and Millennium Pharmaceuticals.

Network-Targeted Cancer Programs.    There are several companies developing drug candidates that target the same cancer pathways that we are also targeting or that are testing drug candidates in the same cancer indications that we are testing through our proprietary network-targeted cancer programs. We believe that our competitive advantage over these companies is our strategy of developing drug candidates that target unique combinations of these cancer pathways to achieve synergistic effect. For example, several companies are investigating Hsp90 inhibitors in clinical testing, including, among others Bristol-Myers Squibb Company, Novartis International AG, Pfizer Inc., Astex Therapeutics Ltd., Myriad Pharmaceuticals Inc., Kyowa Hakko Kirin Co, Ltd., Daiichi Sankyo, and Synta Pharmaceuticals Corp. There are commercially-available drugs that individually target either HDAC or EGFR as well as a drug that targets EGFR/Her2. There are also several drug candidates in clinical testing that are designed to inhibit one or more of these targets. However, we are not aware of other molecules in clinical testing that are designed to simultaneously target HDAC, EGFR and Her2 simultaneously.

Many of the companies competing against us have financial, marketing and human resource capacities that are substantially greater than our own, which may provide these competitors with significant competitive advantages over us. Others have extensive experience in undertaking clinical trials, in obtaining regulatory approval to market products, in manufacturing products on a large scale and in effectively promoting products to healthcare providers, health plans and consumers which may enhance their competitive position relative to ours. In addition to competing with pharmaceutical and biotechnology companies, the products we are developing would also compete with those being developed by academic and research institutions, government agencies and other public organizations. Any of these organizations may discover new therapies, seek patent protection or establish collaborative arrangements for products and technologies that are competitive with our products and technologies.

The technologies underlying the development of human therapeutic products are expected to continue to undergo rapid and significant advancement and unpredictable changes. Accordingly, our technological and commercial success will be based, among other things, on our ability to develop proprietary positions in key scientific areas and efficiently evaluate potential product opportunities.

The timing of a product’s introduction may be a major factor in determining eventual commercial success and profitability. Early entry may have important advantages in gaining product acceptance and market share. Accordingly, we believe the relative speed with which we or any current or future collaborator can complete preclinical and clinical testing, obtain regulatory approvals, and supply commercial quantities of a product will have an important impact on our competitive position, both in the U.S. and abroad. Other companies may succeed in developing similar products that are introduced earlier, are more effective, or are produced and marketed more effectively, or at a minimum obtain a portion of the market share. For example, our competitors may discover, characterize and develop important targeted cancer molecules before we do, which could have a material adverse effect on any of our related research programs. If research and development by others renders any of our products obsolete or noncompetitive, then our potential for success and profitability may be adversely affected.

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For certain of our programs, we rely on, or intend to rely on, strategic collaborators for support in our research programs and for preclinical evaluation and clinical development of our potential products and manufacturing and marketing of any products. Our strategic collaborators may conduct multiple product development efforts within each disease area that is the subject of our strategic collaboration with them. Our strategic collaboration agreements may not restrict the strategic collaborator from pursuing competing internal development efforts. Any of our drug candidates, therefore, may be subject to competition with a drug candidate under development by a strategic collaborator.

Manufacturing

We have no experience or capabilities in manufacturing. We currently rely on collaborators or subcontractors, and we have no plans to develop our own manufacturing capability. Instead, we plan to continue to rely on corporate collaborators or subcontractors to manufacture products. If any of our current or planned collaborators or subcontractors encounters regulatory compliance problems or enforcement actions for their own or a collaborative product, it could have a material adverse effect on our business prospects.

Sales and Marketing

We have no sales, marketing or distribution experience or infrastructure and we have no current plans to develop sales, marketing and distribution capabilities. We currently plan to rely on corporate collaborators for product sales, marketing and distribution.

Employees

As of December 31, 2011, we had 35 full-time employees, of whom 11 hold a Ph.D. or other advanced degree. Of our employees, 25 are currently involved in research and development. None of our employees is a party to a collective bargaining agreement, and we consider our relations with our employees to be good.

Clinical and Scientific Advisory Board

We have established a clinical and scientific advisory board that is comprised of physicians in the field of cancer research and drug development. Members of this board consult with us on matters relating to our research and development programs, including clinical trial design, new technologies relevant to our research and development programs and other scientific and technical issues relevant to our business. In addition to these permanent committee members, the clinical and scientific advisory board from time-to-time engages outside experts, including, for example key opinion leaders in specific cancers targeted by our drug candidates.

The current members of our clinical and scientific advisory board are as follows:

Kenneth J. Pienta, M.D. (Chairman)

Kenneth J. Pienta, M.D., professor of medicine and urology, is the Director of Experimental Therapeutics for the Michigan Center for Translational Pathology. In this role, he oversees the implementation of precision medicine to the care of patients suffering from cancer. He also serves as director for the Specialized Program of Research Excellence (SPORE) grant in prostate cancer at the University of Michigan Comprehensive Cancer Center. As the principal investigator of the $12,000,000 National Cancer Institute grant, Dr. Pienta is responsible for overseeing multidisciplinary efforts to prevent, diagnose and treat prostate cancer.

Dr. Pienta’s research interests include understanding the ecology of the tumor microenvironment. His laboratory focuses on understanding the process of prostate cancer metastasis to bone and discovering novel drug combinations to treat prostate cancer.

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Dr. Pienta joined the University of Michigan Comprehensive Cancer Center in 1994. Previously, he was assistant professor at Wayne State University School of Medicine and deputy director of the Urologic Oncology Program at the Meyer L. Prentis Comprehensive Cancer Center in Detroit. He received his medical degree and was a postdoctoral fellow at Johns Hopkins University in Baltimore.

Philip A. Philip, M.D., Ph.D., F.R.C.P.

Philip A. Philip, M.D., Ph.D., F.R.C.P., is a Professor of Oncology at Wayne State University School of Medicine and the Barbara Ann Karmanos Cancer Institute in Detroit, Michigan. He directs the gastrointestinal cancer program. He is certified by the American Board of Internal Medicine in both Internal Medicine and Medical Oncology. He is also a fellow of the Royal College of Medicine in the United Kingdom. Dr. Philip’s primary research focus is in the clinical trials of novel therapeutic agents and therapeutic combinations on patients with pancreatic, gastro-esophageal, hepatobiliary, neuroendocrine and colorectal cancer. He is actively involved in phase I-III clinical trials with experience as a principal investigator in many trials. He is an active researcher at the national level in the cooperative group mechanism. He has also served on steering committees and data safety monitoring committees of several global studies. He belongs to numerous national and international professional and scientific organizations including the American pancreatic Association, Southwest Oncology Group, International Liver Cancer Association and the American Society of Clinical Oncology.

Dr. Philip serves on the Editorial Board of several cancer journals and reviews for multiple high impact factor impact, including the Journal of Clinical Oncology and the European Journal of Cancer. He has authored over 130 articles in peer-reviewed journals, seven book chapters and many invited review articles. He has also written several invited editorials and co-edited a book on pancreas cancer.

Dr. Philip received his B.A. from the American Jesuits Fathers College in Baghdad, Iraq, M.D. from the University of Baghdad College of Medicine and Ph.D. in Clinical Pharmacology and Pharmacogenetics from the University of London, UK. He trained in oncology at the University of London, the University of Oxford, UK and the MD Anderson Cancer Center in Houston.

Samir E. Witta, M.D., Ph.D.

Samir E. Witta, M.D., Ph.D., launched the Mountain Blue Cancer Care Center in 2009. Dr. Witta specializes in medical oncology and practices at the Mountain Blue Cancer Care Center. He is a Clinical Assistant Professor at the University of Colorado where he is involved in translational research. Dr. Witta received his M.D. from the First Faculty of Medicine, Charles University in Prague. Dr. Witta earned his Ph.D. in genetics and developmental biology from the First Faculty of Medicine, Charles University and from the National Institutes of Health in Bethesda, Maryland. Dr. Witta completed his residency in internal medicine at The Northeastern Pennsylvania Affiliated Residency Program. He then did a fellowship in hematology and medical oncology at the University of Colorado Health Sciences Center in Denver. Dr. Witta is a member of the American Society of Clinical Oncology and the president of the Rocky Mountain Oncology Society.

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Executive Officers of the Registrant

Our executive officers are as follows:

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RISKS RELATING TO THE DEVELOPMENT AND COMMERCIALIZATION OF OUR PRODUCTS

We are reliant on Genentech for the successful development and commercialization of Erivedge. If Genentech does not successfully commercialize Erivedge for advanced BCC, or develop Erivedge for other indications, our future prospects and our ability to finance our operations may be substantially harmed.

In January 2012, Erivedge was approved by the FDA as the first and only FDA-approved medicine for people with advanced forms of BCC. Genentech has also filed and had accepted an MAA with the EMA seeking regulatory approval of Erivedge in the EU for this same indication. Genentech and Roche are also conducting a phase II clinical trial of Erivedge in operable nodular BCC and Erivedge is currently being tested in other cancers under collaborative agreements between Genentech and either third-party investigators or the NCI. Our near-term prospects substantially depend upon Genentech’s ability to successfully develop and commercialize Erivedge in one or more indications and to demonstrate its safety and efficacy, as well as its superiority over existing therapies and standards of care. Moreover, our ability to finance our company and to generate revenues will depend heavily on the ability of Genentech and Roche to: (i) derive meaningful royalties from the commercial sale of Erivedge for advanced BCC, (ii) successfully file regulatory submissions for, and obtain approval to sell, Erivedge in Europe and/or other territories for advanced BCC, and (iii) obtain favorable results in ongoing and planned clinical trials of Erivedge in other indications, including the ongoing clinical trial in operable BCC. The development and commercialization of Erivedge could be unsuccessful if:

The therapeutic efficacy of drug candidates being developed in our network-targeted cancer programs is unproven in humans, and we may not be able to successfully develop and commercialize CUDC-101 or any other future drug candidates that we may select from these programs.

Our drug candidates in our network-targeted cancer program, including CUDC-101, Debio 0932 and CUDC-907, are novel compounds and their potential benefit as therapeutic cancer drugs is unproven. These drug candidates may not prove to be effective inhibitors of the validated cancer targets they are being designed to act against and

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may not demonstrate in patients any or all of the pharmacological benefits that we believe they may possess or that may have been demonstrated in preclinical studies. Moreover, there is a risk that these drug candidates may interact with human biological systems in unforeseen, ineffective or harmful ways. As a result of these and other risks described herein that are inherent in the development of novel therapeutic agents, we may never successfully develop, enter into or maintain third party licensing or collaboration transactions with respect to, or successfully commercialize CUDC-101, CUDC-907 or Debio 0932, or any other drug candidates from our network-targeted cancer programs, in which case we will not achieve profitability and the value of our stock will decline.

We depend on third parties for the development of certain of our programs. If one or more of our collaborators fails or delays in developing or commercializing drug candidates based upon our technologies, our business prospects and operating results would suffer and our stock price would likely decline.

We currently have a collaboration with Genentech pursuant to which we have granted to Genentech exclusive rights to develop and commercialize products based upon our Hedgehog pathway technologies. Genentech recently obtained FDA approval to commercialize Erivedge, the sole compound being developed under this collaboration, in advanced BCC. Genentech is also seeking to obtain regulatory approval for this same indication in the EU, and is also conducting, both alone and in collaboration, further studies of Erivedge for other indications. In addition, we entered into a license agreement with Debiopharm pursuant to which Debiopharm is testing Debio 0932 in a phase Ib clinical trial in advanced solid tumors. Our collaboration agreement with Genentech and our license agreement with Debiopharm are our most significant collaborations, and these collaborations may not be scientifically or commercially successful due to a number of factors, including the following:

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If Genentech or Debiopharm fails to successfully develop and commercialize our drug candidates under collaboration, we may not be able to develop and commercialize these candidates independently or successfully enter into one or more alternative collaborations, in which event our financial condition, results of operations and stock price may be adversely affected.

For a further discussion of risks relating specifically to our dependence on Genentech for the successful development and commercialization of Erivedge, see: “We are reliant on Genentech for the successful development and commercialization of Erivedge. If Genentech does not successfully commercialize Erivedge for advanced BCC, or develop Erivedge for other indications, our future prospects and our ability to finance our operations will be substantially harmed.”

We may not be successful in establishing additional strategic collaborations, which could adversely affect our ability to develop and commercialize products.

Our current strategy is to seek corporate collaborators or licensees for the further development and commercialization of one or more drug candidates under our network-targeted cancer drug programs, generally following our completion of at least phase I clinical testing. For example, while we are not presently seeking to enter into corporate collaborations for CUDC-101, we are likely to seek to partner CUDC-101, CUDC-907 as well as other drug candidates from these programs in the future. We do not currently have the experience, resources or capacity to advance these programs into later stage clinical development (i.e., phase III) or commercialization. As such, our success will depend, in part, on our ability to enter into one or more such

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collaborations. We face significant competition in seeking appropriate collaborators and the negotiation process is time-consuming and complex. Moreover, we may not be successful in our efforts to establish a collaboration or other alternative arrangements for CUDC-101, CUDC-907 or any future programs because our research and development pipeline may be insufficient, our programs may be deemed to be at too early of a stage of development for collaborative effort and/or third parties may not view our drug candidates and programs as having the requisite potential to demonstrate safety and efficacy or sufficient differentiability compared to existing or emerging treatments. Even if we are successful in our efforts to establish new collaborations, the terms that we agree upon may not be favorable to us.

Moreover, if we fail to establish and maintain additional strategic partnerships related to our product candidates:

If preclinical studies and clinical trials of our drug candidates are not successful then our future profitability and success could be adversely affected.

In order to obtain regulatory approval for the commercial sale of our drug candidates, we and any current or potential future collaborators will be required to complete extensive preclinical studies as well as clinical trials in humans to demonstrate to the FDA and foreign regulatory authorities that our drug candidates are safe and effective for each indication for which approval is sought.

Development, including preclinical and clinical testing, is a long, expensive and uncertain process. Preclinical testing and clinical trials of our drug candidates may not be successful. We and our collaborators could experience delays or failures in preclinical testing or clinical trials of any of our drug candidates for a number of reasons including, for example:

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If the preclinical studies and/or clinical trials for any of our drug candidates that we and any collaborators pursue are not successful, then our ability to successfully develop and commercialize products on the basis of the respective technologies will be materially adversely affected, our reputation and our ability to raise additional capital will be materially impaired and our stock price is likely to decline.

We expect to rely in part on third parties to conduct clinical trials of our internally-developed product candidates, and if such third parties perform inadequately then we will not be able to successfully develop and commercialize drug candidates and grow our business.

We have a limited internal group for overseeing our clinical trials, currently comprised of our chief medical and development officer, our director of development and our clinical operations manager. In the near term, we expect to rely in part on third parties such as consultants, contract research organizations and other similar entities to complete IND-enabling preclinical studies, assist us in creating and submitting IND applications, enroll qualified subjects, conduct our clinical trials and provide services in connection with such clinical trials. Our reliance on these third parties for clinical development activities will reduce our control over these activities. These third parties may not complete activities on schedule, or at all, or may not conduct our clinical trials in accordance with the clinical trial protocol or design. In addition, the FDA and its foreign equivalents require us to comply with certain standards, referred to as good clinical practices, and applicable regulatory requirements, for conducting, recording and reporting the results of clinical trials to assure that data and reported results are credible and accurate and that the rights, integrity and confidentiality of trial participants are protected. Our reliance on third parties that we do not control does not relieve us of these responsibilities and requirements. If any of the third party contractors on whom we rely do not comply with good clinical practices or other applicable regulatory requirements, we may not be able to use the data and reported results from the applicable trial. Any failure by a third party to conduct our clinical trials as planned or in accordance with regulatory requirements could delay or otherwise adversely affect our efforts to obtain regulatory approvals for and commercialize our drug candidates.

If we and our collaborative partners do not obtain necessary regulatory approvals, then our business will be unsuccessful and the market price of our common stock could substantially decline.

We and our collaborators will be required to obtain regulatory approval in order to successfully advance drug candidates through the clinic and prior to marketing and selling such products. The process of obtaining required regulatory approvals is expensive and the time required for these approvals is uncertain and typically takes a number of years, depending on the type, complexity and novelty of the product. With respect to our internal programs, we have limited experience in filing and prosecuting applications to obtain marketing approval.

Any regulatory approval to market a product may be subject to limitations on the approved indicated uses for which we or our collaborative partners may market the product or to distribution and use restrictions or other requirements under a Risk Evaluation and Mitigation Strategy, or REMS. These limitations may restrict the size of the market for the product and affect reimbursement by third-party payors. In addition, regulatory agencies may not grant approvals on a timely basis or may revoke or significantly modify previously granted approvals.

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We and our collaborators are subject to numerous foreign regulatory requirements governing the manufacturing and marketing of potential future products outside of the United States. The approval procedure varies among countries, additional testing may be required in some jurisdictions, and the time required to obtain foreign approvals often differs from that required to obtain FDA approvals. Moreover, approval by the FDA or a foreign equivalent does not ensure approval by regulatory authorities in other countries, and vice versa.

In addition, regulatory agencies may change existing requirements or adopt new requirements or policies. We and any collaborative partners may be slow to adapt or may not be able to adapt to these changes or new requirements.

As a result of these factors, we and any collaborators may not successfully begin or complete clinical trials and/or obtain regulatory approval to market and sell drug candidates in the time periods estimated, if at all. Moreover, if we or any collaborators incur costs and delays in development programs or fail to successfully develop and commercialize products based upon our technologies, we may not become profitable and our stock price could decline.

Even if marketing approval is obtained, any products we or any collaborators develop will be subject to ongoing regulatory oversight, which may affect the successful commercialization of such products.

Even if we or any collaborators obtain regulatory approval of a drug candidate, the approval may be subject to limitations on the approved indicated uses for which the product can be marketed, impose restrictions on how the product can be distributed and used pursuant to a REMS, or require costly post-marketing follow-up studies. After marketing approval for any product is obtained, the manufacturer and the manufacturing facilities for that product will be subject to continual review and periodic inspections by the FDA, or foreign equivalent, and other regulatory agencies. The subsequent discovery of previously unknown problems with the product, or with the manufacturer or facility, or a failure to comply with regulatory requirements, may result in restrictions on the product or manufacturer, including withdrawal of the product from the market, fines, refusal to approve pending applications or supplements, suspension or withdrawal of regulatory approvals, product recalls, seizure of products, operating restrictions, refusal to permit the import or export of our products or those of our collaborators, and criminal prosecution.

The FDA’s policies may change and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our or our collaborators’ product candidates. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in the United States or abroad. If we or our collaborators are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we or they may lose any marketing approvals that have been obtained, which would adversely affect the amount of revenue generated from such products and adversely affect our ability to achieve or sustain profitability.

We and our current collaborators are, and any potential future collaborators will be, subject to governmental regulations in connection with the research, development and commercialization of our drug candidates. We and our collaborators may not be able to comply with these regulations, which could subject us or such collaborators to penalties and result in the imposition of limitations on our or such collaborators’ operations.

In addition to regulations imposed by the FDA or foreign equivalents, we and our current collaborators are, and any potential future collaborators will be, subject to regulation under, among other laws, the Occupational Safety and Health Act, the Environmental Protection Act, the Toxic Substances Control Act, the Research Conservation and Recovery Act, as well as regulations administered by the Nuclear Regulatory Commission, national restrictions on technology transfer, import, export and customs regulations and certain other local, state or federal regulations. From time to time, other federal agencies and congressional committees have indicated an

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interest in implementing further regulation of pharmaceutical and biotechnology companies. We are not able to predict whether any such regulations will be adopted or whether, if adopted, such regulations will apply to our business, or whether we or any collaborators would be able to comply with any applicable regulations.

Our business involves the use of hazardous materials and we must comply with environmental laws and regulations, which can be expensive and restrict how we do business.

Our research and development activities involve the controlled use of hazardous materials and chemicals. Although we believe that our safety procedures for handling and disposing of such materials comply with all applicable laws and regulations, we cannot completely eliminate the risk of accidental contamination or injury caused by these materials. Violation of these laws and regulations could lead to substantial fines and penalties. In the event of an accident, state or federal authorities may curtail our use of these materials and interrupt our business operations. In addition, we could become subject to potentially material liabilities relating to the investigation and cleanup of any contamination, whether currently unknown or caused by future releases.

Our business and operations would suffer in the event of system failures.

Despite the implementation of security measures, our internal computer systems are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. Any system failure, accident or security breach that causes interruptions in our operations could result in a material disruption of our product development programs. To the extent that any disruption or security breach results in a loss or damage to our data or applications, or inappropriate disclosure of confidential or proprietary information, we may incur liability and the further development of our product candidates may be delayed.

If we or any of our collaborators fail to achieve market acceptance for any approved products, our future revenue and ability to achieve profitability may be adversely affected.

Our future products, including those developed under collaborations with third parties, may not gain commercial acceptance among physicians, patients and third-party payors, even if necessary marketing approvals have been obtained. We believe that recommendations and endorsements by physicians will be essential for market acceptance of any products we or our collaborators successfully develop. If we or our collaborators are not able to obtain market acceptance for such products, our expected revenues from sales of these products would be adversely affected and our business may not be successful.

RISKS RELATING TO OUR FINANCIAL RESULTS AND NEED FOR FINANCING

We have incurred substantial losses, expect to continue to incur substantial losses for the foreseeable future and may never generate significant revenue or achieve profitability.

As of December 31, 2011, we had an accumulated deficit of approximately $732,088,000. We have incurred net losses of $9,859,000, $4,435,000 and $9,823,000 for the years ended December 31, 2011, 2010, and 2009, respectively. Other than Erivedge, which was approved by the FDA in January 2012 for the treatment of advanced forms of basal cell carcinoma, we have not successfully commercialized any products to date, either alone or in collaboration with others. We are entitled to royalties on net sales of Erivedge by Genentech. If these royalties are not meaningful or we are not able to successfully commercialize any products, we will not achieve profitability. All of our drug candidates other than Erivedge are in early stages of development. For the foreseeable future, we will need to spend significant capital in an effort to develop and commercialize products and we expect to incur substantial operating losses. Our failure to become and remain profitable would, among other things, depress the market price of our common stock and could impair our ability to raise capital, expand our business, diversify our research and development programs or continue our operations.

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We will require substantial additional capital, which is likely to be difficult to obtain.

We will require substantial funds to continue our research and development programs and to fulfill our planned operating goals. In particular, our currently planned operating and capital requirements include the need for substantial working capital to support our research and development activities for CUDC-101, CUDC-907 and other small molecules that we are seeking to develop from our pipeline of network-targeted cancer programs, and to fund our general and administrative costs and expenses.

We have historically derived a substantial portion of our operating cash flow from the research funding portion of collaboration agreements with third parties. However, we have no current research funding revenue under collaboration agreements. Our only potential source of cash flows from operations for the foreseeable future is contingent payments that we could receive under existing or new collaborations as follows:

We may not be able to successfully enter into or continue any corporate collaborations and the timing, amount and likelihood of us receiving payments under such collaborations is highly uncertain. As a result, we cannot assure you that we will attain adequate future operating capital, if any, from collaborations or licensing arrangements.

We anticipate that existing cash, cash equivalents, marketable securities and working capital at December 31, 2011 should enable us to maintain current and planned operations into the second half of 2013. Our future capital requirements, however, may vary from what we currently expect. There are a number of factors that may affect our planned future capital requirements and accelerate our need for additional working capital, many of which are outside our control, including the following:

Additional funds may not be available when we need them, on terms that are acceptable to us, or at all. If adequate funds are not available to us on a timely basis, we may be required to:

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Raising additional capital may cause dilution to our existing stockholders, restrict our operations or require us to relinquish rights to our technologies or product candidates.

We may seek additional funding through public or private financings of debt or equity. For example, in June 2011 we entered into an agreement with McNicoll, Lewis & Vlak, LLC, or MLV, pursuant to which, from time to time, we may offer and sell up to $20 million of common stock through MLV pursuant to one or more “at the market” offerings. In addition, with our prior written approval, MLV may also sell these shares of common stock by any other method permitted by law, including in privately negotiated transactions. The market for emerging life science stocks in general, and the market for our common stock in particular, are highly volatile. Due to this and various other factors, including adverse general market conditions and the early-stage status of our development pipeline, additional funding may not be available to us on acceptable terms, if at all, and we may not be able to sell additional shares under the arrangement with MLV at favorable prices, if at all. In addition, the terms of any financing may be dilutive or otherwise adversely affect other rights of our stockholders. We also expect to seek additional funds through arrangements with collaborators, licensees or other third parties. These arrangements would generally require us to relinquish or encumber rights to some of our technologies or drug candidates. Moreover, we may not be able to enter into such arrangements on acceptable terms, if at all. If we are unable to obtain additional funding on a timely basis, whether through sales of debt or equity or through third party collaboration or license arrangements, we may be required to curtail or terminate some or all of our development programs.

We may face fluctuations in our operating results from period to period, which may result in a decline in our stock price.

Our operating results have fluctuated significantly from period to period in the past and may rise or fall significantly from period to period in the future as a result of many factors, including:

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Due to fluctuations in our operating results, quarterly comparisons of our financial results may not necessarily be meaningful, and investors should not rely upon such results as an indication of our future performance. In addition, investors may react adversely if our reported operating results are less favorable than in a prior period or are less favorable than those anticipated by investors or the financial community, which may result in a decline in our stock price.

Unstable market and economic conditions may have serious adverse consequences on our business, financial condition and stock price.

Our general business strategy and prospects may be adversely affected by the unfavorable economic conditions, volatile business environment and continued unpredictable and unstable market conditions, both domestically and abroad. If equity and credit markets are unfavorable, it may make future debt or equity financing more difficult, more costly, and more dilutive. Failure to secure any necessary financing in a timely manner and on favorable terms could have a material adverse effect on our growth strategy, financial performance and stock price and could require us to delay or abandon research and development plans. In addition, there is a risk that one or more of our current service providers, manufacturers and other partners may not survive these difficult economic times, which could directly affect our ability to attain our operating goals on schedule and on budget.

At December 31, 2011, we had $37,718,000 of cash, cash equivalents and marketable securities consisting of cash, money market, commercial paper, corporate debt securities, and government obligations. While as of the date of this filing, we are not aware of any downgrades, material losses, or other significant deterioration in the fair value of our cash equivalents or marketable securities since December 31, 2011, no assurance can be given that further deterioration in conditions of the global credit and financial markets would not negatively impact our current portfolio of cash equivalents or marketable securities or our ability to meet our financing objectives. Further dislocations in the credit market may adversely impact the value and liquidity of marketable securities owned by us.

There is a possibility that our stock price may decline due to the volatility of the stock market and the general economic downturn.

RISKS RELATED TO OUR BUSINESS, INDUSTRY, STRATEGY AND OPERATIONS

We and our collaborators may not achieve projected research and development goals in the time frames that we or they announce, which could have an adverse impact on our business and could cause our stock price to decline.

We set goals for, and make public statements regarding, the timing of certain accomplishments, such as the commencement and completion of preclinical studies, initiation and completion of clinical trials, and other developments and milestones under our proprietary programs and those programs being developed under collaboration agreements. Genentech has also made public statements regarding its expectations for the clinical development and potential filing of additional regulatory submissions for approval of Erivedge, and may in the future make additional statements about its goals and expectations for this collaboration with us. The actual timing of these events can vary dramatically due to a number of factors including without limitation delays or failures in our and our current and potential future collaborators’ preclinical studies or clinical trials, the amount of time, effort and resources committed to our programs by us and our current and potential future collaborators and the uncertainties inherent in the regulatory approval process. As a result, we can not assure you that our or our current and potential future collaborators’ preclinical studies and clinical trials will advance or be completed in the time frames we or they announce or expect, that we or our current and potential future collaborators will make regulatory submissions or receive regulatory approvals as planned or that we or our current and potential future collaborators will be able to adhere to our current schedule for the achievement of key milestones under any of our internal or collaborative programs. If we or any collaborators fail to achieve one or more of these milestones as planned, our business could be materially adversely affected and the price of our common stock could decline.

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We face substantial competition, which may result in our competitors discovering, developing or commercializing products before or more successfully than we do.

Our drug candidates face competition from existing and new technologies and products being developed by biotechnology, medical device and pharmaceutical companies, as well as universities and other research institutions. For example, there are several Hedgehog pathway inhibitors presently in clinical development by companies including Bristol-Myers Squibb, Infinity Pharmaceuticals, Millenium Pharmaceuticals, Novartis and Pfizer that may compete with Erivedge. We currently believe that the nearest competitive molecule to Erivedge in clinical development is in Phase II clinical testing in locally advanced and metastatic basal cell carcinoma . We are developing Hedgehog-based therapies under our collaborations with Genentech in the field of cancer. Competitors may discover, characterize and develop Hedgehog pathway inhibitor drug candidates before we do or may compete with us in the same market sector.

In addition, our small molecule network-targeted cancer drug development candidates, which are focused primarily on validated cancer targets, face significant competition from marketed drugs and drugs under development that seek to inhibit the same targets as our drug candidates. We expect competition to intensify in cancer generally and, specifically, in targeted approaches to develop potential cancer therapies as technical advances in the field are made and become more widely known.

Many of our competitors have substantially greater capital resources, research and development staffs and facilities, and more extensive experience than we have. As a result, efforts by other life science, medical device and pharmaceutical companies could render our programs or products uneconomical or result in therapies superior to those that we develop alone or with a collaborator.

For those programs that we have selected for internal development, we face competition from companies that are more experienced in product development and commercialization, obtaining regulatory approvals and product manufacturing. Other smaller companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. As a result, any of these companies may be more successful in obtaining collaboration agreements or other monetary support, approval and commercialization of their products and/or may develop competing products more rapidly and/or at a lower cost. For those programs that are subject to a collaboration agreement, competitors may have greater expertise in discovery, research and development, manufacturing, preclinical and clinical testing, obtaining regulatory approvals and marketing than our collaborators and, consequently, may discover, develop and commercialize products that render our products non-competitive or obsolete.

If we are not able to compete effectively, then we may not be able, either alone or with others, to advance the development and commercialization of our drug candidates, which would adversely affect our ability to grow our business and become profitable.

The trend towards consolidation in the pharmaceutical and biotechnology industries may adversely affect us.

There is a trend towards consolidation in the pharmaceutical and biotechnology industries. This consolidation trend may result in the remaining companies in these industries having greater financial resources and technological capabilities, thus intensifying competition in these industries. This trend may also result in fewer potential collaborators or licensees for our therapeutic drug candidates. Also, if a consolidating company is already doing business with our competitors, we may lose existing licensees or collaborators as a result of such consolidation. This trend may adversely affect our ability to enter into agreements for the development and commercialization of our drug candidates, and as a result may harm our business.

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We could be exposed to significant monetary damages and business harm if we are unable to obtain or maintain adequate product liability insurance at acceptable costs or otherwise protect ourselves against potential product liability claims.

Product liability claims are inherent in the process of researching, developing and commercializing human health care products could expose us to significant liabilities and prevent or interfere with the development or commercialization of our drug candidates. Regardless of their merit or eventual outcome, product liability claims would require us to spend significant time, money and other resources to defend such claims, could result in decreased demand for our future products or result in reputational harm and could result in the payment of a significant damage award.

Although we currently have product liability insurance for our clinical trials, this insurance is subject to deductibles and coverage limitations and may not be adequate in scope to protect us in the event of a successful product liability claim. If any of our drug candidates advance in clinical trials and/or are approved for marketing, we may seek additional insurance coverage. Product liability insurance is expensive and may be difficult to procure. As such, it is possible that we will not be able to obtain product liability insurance on acceptable terms, if at all, or that our product liability insurance coverage will prove to be inadequate to protect us from all potential claims, which may harm our business.

If we are not able to attract and retain key management and scientific personnel and advisors, we may not successfully develop our drug candidates or achieve our other business objectives.

We depend upon our senior management, including Daniel R. Passeri, our President and Chief Executive Officer, Maurizio Voi, our Chief Medical and Chief Development Officer, and Michael P. Gray, our Chief Operating Officer and Chief Financial Officer. The loss of the service of any of the key members of our senior management may significantly delay or prevent the achievement of product development and other business objectives. Our officers all serve pursuant to “at will” employment arrangements and can terminate their employment with us at any time. We do not maintain key man life insurance on any of these officers. Replacing key employees may be difficult and may take an extended period of time because of the limited number of individuals in our industry with the breadth of skills and experience required to research, develop and successfully commercialize products in our areas of core competency.

Our ability to operate successfully will depend on our ability to attract and retain qualified personnel, consultants and advisors. We face intense competition for qualified individuals from numerous pharmaceutical and biotechnology companies, universities, governmental entities and other research institutions. We may be unable to attract and retain these individuals, and our failure to do so would have an adverse effect on our business.

We may seek to acquire complementary businesses and technologies or otherwise seek to expand our operations to grow our business, which may divert management resources and adversely affect our financial condition and operating results.

We may seek to expand our operations, including without limitation through internal growth and/or the acquisition of businesses and technologies that we believe are a strategic complement to our business model. We may not be able to identify suitable acquisition candidates or expansion strategies and successfully complete such acquisitions or successfully execute any such other expansion strategies. We may never realize the anticipated benefits of any efforts to expand our business. Furthermore, the expansion of our business, either through internal growth or through acquisitions, poses significant risks to our existing operations, financial condition and operating results, including:

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Any business that we conduct in China will expose us to risks resulting from adverse changes in political, legal and economic policies of the Chinese government, which could impede our preclinical efforts in China and materially and adversely affect the development of our network-targeted cancer programs.

We currently engage approximately 16 medicinal chemists in China pursuant to a contract research agreement with a medicinal chemistry provider in China. In addition, we have a subsidiary in China, Curis Shanghai, which is currently licensed to conduct business but is not operational.

Conducting business in China exposes us to a variety of risks and uncertainties that are unique to China. The economy of China has been transitioning from a planned economy to a more market-oriented economy. Although in recent years the Chinese government has implemented measures emphasizing the utilization of market forces for economic reform, the reduction of state ownership of productive assets and the establishment of sound corporate governance in business enterprises, a substantial portion of productive assets in China is still owned by the Chinese government. In addition, the Chinese government continues to play a significant role in regulating industrial development. It also exercises significant control over China’s economic growth through the allocation of resources, controlling payment of foreign currency-denominated obligations, setting monetary policy and providing preferential treatment to particular industries or companies. Efforts by the Chinese government to slow the pace of growth of the Chinese economy could result in interruptions of our development efforts in China. If our research and development efforts in China are delayed due to such interruptions, we may not realize the reductions in costs anticipated from doing business in China. We would also have to consider moving our chemistry and/or biology research that is currently conducted in China to U.S. or European providers, thereby potentially either increasing our overall costs for such services or reducing the total number of chemists and or/biologists that we could engage.

In addition, the Chinese legal system is a civil law system based on written statutes. Unlike common law systems, it is a system in which decided legal cases have little precedential value. In 1979, the Chinese government began to promulgate a comprehensive system of laws and regulations governing economic matters in general. Accordingly, we cannot predict the effect of future developments in the Chinese legal system, including the promulgation of new laws, changes to existing laws or the interpretation or enforcement thereof, or the preemption of local regulations by national laws. Our business could be materially harmed by any changes in the political, legal or economic climate in China or the inability to enforce applicable Chinese laws and regulations.

If the estimates we make and the assumptions on which we rely in preparing our financial statements prove inaccurate, our actual results may vary significantly.

Our financial statements have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of our assets, liabilities, revenues and expenses, the amounts of charges taken by us and related disclosure. Such estimates and judgments include the carrying value of our property, equipment and intangible assets, revenue recognition, the value of certain liabilities, including the fair value of our warrant liability, and stock-based compensation expense. We base our estimates and judgments on historical experience and on various other assumptions that we believe to be reasonable under the circumstances. However, these estimates and judgments, or the assumptions underlying them, may change over time. Accordingly, our actual financial results may vary significantly from the estimates contained in our financial statements.

For a further discussion of the estimates and judgments that we make and the critical accounting policies that affect these estimates and judgments, see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Estimates” elsewhere in this Annual Report on Form 10-K.

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Our employees may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements and insider trading.

We are exposed to the risk of employee fraud or other misconduct. Misconduct by employees could include intentional 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 laws and regulations, to report financial information or data accurately or to disclose unauthorized activities to us. Employee misconduct could also involve the improper use of information obtained in the course of clinical trials, which could result in regulatory sanctions and serious harm to our reputation. We have adopted a Code of Business Conduct and Ethics, but it is not always possible to identify and deter employee misconduct, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to be in compliance with such laws or regulations.

If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business, including the imposition of significant fines or other sanctions. 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. Despite our adoption of an Insider Trading Policy, 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 from other tasks important to the success of our business.

RISKS RELATING TO OUR INTELLECTUAL PROPERTY

We may not be able to obtain patent protection for our technologies and the patent protection we do obtain may not be sufficient to stop our competitors from using similar technology.

The long-term success of our business depends in significant part on our ability to:

The patent positions of pharmaceutical and life science companies, including ours, are generally uncertain and involve complex legal, scientific and factual questions. The laws, procedures and standards that the United States Patent and Trademark Office and various foreign intellectual property offices use to grant patents, and the standards that courts use to interpret patents, are not always applied predictably or uniformly and have changed in significant ways and are expected to continue to change. Consequently, the level of protection, if any, that will be obtained and provided by our patents if we attempt to enforce them, and they are challenged, is uncertain.

Patents may not issue from any of the patent applications that we own or license. If patents do issue, the type and extent of patent claims issued to us may not be sufficient to protect our technology from exploitation by our competitors. In addition, issued patents that we own or license may be challenged, invalidated or circumvented. Our patents also may not afford us protection against competitors with similar technology. Because patent applications in the United States and in many countries abroad are maintained in secrecy until 18 months after filing, it is possible that third parties have filed or maintained patent applications for technology used by us or covered by our pending patent applications without our knowledge. The U.S. Congress recently

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passed the Leahy-Smith America Invents Act, or the America Invents Act, which was signed into law in September 2011. The America Invents Act reforms United States patent law in part by changing the standard for patent approval from a “first to invent” standard to a “first to file” standard and developing a post-grant review system. This new legislation changes United States patent law in a way that may weaken our ability to obtain or maintain patent protection for future inventions in the United States.

We may not have rights under patents that may cover one or more of our drug candidates. In some cases, these patents may be owned or controlled by third-party competitors and may prevent or impair our ability to exploit our technology. As a result, we or our current or potential future collaborative partners may be required to obtain licenses under third-party patents to develop and commercialize some of our drug candidates. If we are unable to secure licenses to such patented technology on acceptable terms, we or our collaborative partners may not be able to develop and commercialize the affected drug candidate or candidates.

We may become involved in expensive and unpredictable patent litigation or other intellectual property proceedings, which could result in liability for damages or require us to cease our development and commercialization efforts.

There are substantial litigation and other adversarial opposition proceedings regarding patent and other intellectual property rights in the pharmaceutical and life science industries. We may become a party to patent litigation or other proceedings regarding intellectual property rights.

Situations that may give rise to patent litigation or other disputes over the use of our intellectual property include:

The costs associated with any patent litigation or other proceeding, even if resolved favorably, will likely be substantial and a distraction to management. Some of our competitors may be able to sustain the cost of such litigation or other proceedings more effectively than we can because of their substantially greater financial resources. If a patent litigation or other intellectual property proceeding is resolved unfavorably, we or any collaborative partners may be enjoined from manufacturing or selling our future products without a license from the other party and be held liable for significant damages. Moreover, we may not be able to obtain required licenses on commercially acceptable terms or any terms at all. In addition, we could be held liable for lost profits if we are found to have infringed a valid patent, or liable for treble damages if we are found to have willfully infringed a valid patent. Litigation results are highly unpredictable and we or any collaborative partner may not prevail in any patent litigation or other proceeding in which we may become involved. Any changes in, or unexpected interpretations of the patent laws may adversely affect our ability to enforce our patent position. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could damage our ability to compete in the marketplace.

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We face risks relating to the enforcement of our intellectual property rights in China that could adversely affect our business.

Pursuant to our contract research agreement with a medicinal chemistry provider in China, we currently engage approximately 16 medicinal chemists in China to perform drug discovery research. We seek to protect our intellectual property rights under this arrangement through, among other things, non-disclosure and assignment of invention covenants. Implementation and enforcement of Chinese intellectual property-related laws has historically been inconsistent and damages assessed may fail to reflect the true value of the infringed technology and its market. Accordingly, intellectual property rights and confidentiality protections in China may not be as effective as in the United States or other countries. Policing unauthorized use of proprietary technology is difficult and expensive, and we might need to resort to litigation to enforce or defend patents issued to us or to determine the enforceability, scope and validity of our proprietary rights or those of others. The experience and capabilities of Chinese courts in handling intellectual property litigation varies, and outcomes are unpredictable. Further, such litigation may require significant expenditure of cash and management efforts and could harm our business, financial condition and results of operations. An adverse determination in any such litigation will impair our intellectual property rights and may harm our business, prospects and reputation.

If we are unable to keep our trade secrets confidential, our technology and proprietary information may be used by others to compete against us.

We rely significantly upon proprietary technology, information, processes and know-how that are not subject to patent protection. We seek to protect this information through confidentiality and intellectual property license or assignment provisions in agreements with our employees, consultants and other third-party contractors, including our contract research agreement with a medicinal chemistry provider in China, as well as through other security measures. The confidentiality and intellectual property provisions of our agreements and security measures may be breached, and we may not have adequate remedies for any such breach. In addition, our trade secrets may otherwise become known or be independently developed by competitors.

If we fail to comply with our obligations in the agreements under which we license rights to technology from third parties, we could lose license rights that are important to our business.

We are party to agreements that provide for licenses to us of intellectual property or sharing of rights to intellectual property that is important to our business, and we may enter into additional agreements in the future that provide licenses to us of valuable technology. These licenses impose, and future licenses may impose, various commercialization, milestone and other obligations on us, including the obligation to terminate our use of patented subject matter under certain contingencies. If a licensor becomes entitled to, and exercises, termination rights under a license, we would lose valuable rights and could lose our ability to develop our products. We may need to license other intellectual property to commercialize future products. Our business may suffer if any current or future licenses terminate, if the licensors fail to abide by the terms of the license or fail to prevent infringement by third parties, if the licensed patents or other rights are found to be invalid or if we are unable to enter into necessary licenses on acceptable terms.

We may be subject to claims that our employees have wrongfully used or disclosed alleged trade secrets of their former employers.

As is common in the biotechnology and pharmaceutical industry, we employ individuals who were previously employed at other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Although no claims against us are currently pending, 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. 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.

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RISKS RELATING TO MANUFACTURING AND SALES

We will depend on our collaborators and third-party manufacturers to produce most, if not all, of our products under development, and if these third parties do not successfully formulate or manufacture these products, our business will be harmed.

We have no manufacturing experience or manufacturing capabilities. In order to continue to develop drug candidates, apply for regulatory approvals, and commercialize our products under development, we or any collaborators must be able to manufacture products in adequate clinical and commercial quantities, in compliance with regulatory requirements, including those related to quality control and quality assurance, at acceptable costs and in a timely manner. The manufacture of our drug candidates may be complex, difficult to accomplish and difficult to scale-up when large-scale production is required. Manufacture may be subject to delays, inefficiencies and poor or low yields of quality products. The cost of manufacturing some of our product candidates may make them prohibitively expensive.

To the extent that we or any collaborators seek to enter into manufacturing arrangements with third parties, we and such collaborators will depend upon these third parties to perform their obligations in a timely and effective manner and in accordance with government regulations. Contract manufacturers may breach their manufacturing agreements because of factors beyond our and our collaborators’ control or may terminate or fail to renew a manufacturing agreement based on their own business priorities at a time that is costly or inconvenient for us and our collaborators.

Any contract manufacturers with whom we or our collaborators enter into manufacturing arrangements will be subject to ongoing periodic, unannounced inspection by the FDA and corresponding state and foreign agencies or their designees to ensure strict compliance with current good manufacturing practices and other governmental regulations and corresponding foreign standards. Any failure by our or our collaborators’ contract manufacturers, any collaborators, or us to comply with applicable regulations could result in sanctions being imposed, including fines, injunctions, civil penalties, failure of regulatory authorities to grant marketing approval of drug candidates, delays, suspension or withdrawal of approvals, seizures or recalls of drug candidates, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect our business. If we or a collaborator need to change manufacturers, the FDA and corresponding foreign regulatory agencies must approve any new manufacturers in advance. This would involve testing and pre-approval inspections to ensure compliance with FDA and foreign regulations and standards.

If third-party manufacturers fail to perform their obligations, our competitive position and ability to generate revenue may be adversely affected in a number of ways, including;

Because we rely on a limited number of suppliers for the raw materials used in our product candidates, any delay or interruption in the supply of such raw materials could lead to delays in the manufacture and supply of our product candidates.

We rely on third parties to supply certain raw materials necessary to produce our drug candidates, including CUDC-101, for preclinical studies and clinical trials. There are a small number of suppliers for certain raw materials that we use to manufacture our drug candidates. Such suppliers may not sell these raw materials to us at the times we need them or on commercially reasonable terms, or delivery of these raw materials may be delayed or interrupted. Although we generally do not begin a preclinical study or clinical trial unless we believe we have a sufficient supply of a drug candidate to complete such study or trial, any significant delay in the supply of raw

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materials for our drug candidates for an ongoing clinical trial due to the need to replace a third-party supplier could considerably delay completion of certain preclinical studies and/or clinical trials. Moreover, if we were unable to purchase raw materials after regulatory approval had been obtained for our drug candidates, the commercial launch of our drug candidates would be delayed or there would be a shortage in supply, which would impair our ability to generate revenues from the sale of our drug candidates.

We have no sales or marketing experience and, as such, plan to depend significantly on third parties who may not successfully market and sell any products we develop.

We have no sales, marketing or product distribution experience. If we receive required regulatory approvals, we plan to rely primarily on sales, marketing and distribution arrangements with third parties, including our collaborative partners. For example, as part of our agreements with Genentech and Debiopharm, we have granted Genentech and Debiopharm the exclusive rights to distribute certain products resulting from such collaborations, if any are ever successfully developed. We may have to enter into additional marketing arrangements in the future and we may not be able to enter into these additional arrangements on terms that are favorable to us, if at all. In addition, we may have limited or no control over the sales, marketing and distribution activities of these third parties and sales through these third parties could be less profitable to us than direct sales. These third parties could sell competing products and may devote insufficient sales efforts to our products. Our future revenues will be materially dependent upon the success of the efforts of these third parties.

We may seek to independently market products that are not already subject to marketing agreements with other parties. If we determine to perform sales, marketing and distribution functions ourselves, we could face a number of additional risks, including:

Even if we successfully commercialize any products under development, either alone or in collaboration, we face uncertainty with respect to pricing, third-party reimbursement and healthcare reform, all of which could adversely affect the commercial success of our product candidates.

Our ability to collect significant revenues from sales of our products, if commercialized successfully, may depend on our ability, and the ability of any current or potential future collaboration partners or customers, to obtain adequate levels of coverage and reimbursement for such products from third-party payers such as:

Third party payers are increasingly challenging the prices charged for medical products and services. For example, third-party payers may deny coverage or offer inadequate levels of reimbursement if they determine that a prescribed product has not received appropriate clearances from the FDA, or foreign equivalent, or other government regulators, is not used in accordance with cost-effective treatment methods as determined by the third-party payer, or is experimental, unnecessary or inappropriate. Prices could also be driven down by health maintenance organizations that control or significantly influence purchases of healthcare services and products. If third-party payers deny coverage or offer inadequate levels of reimbursement, we or any collaborators may not be able to market our products effectively or we may be required to offer our products at prices lower than anticipated.

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In both the U.S. and some foreign jurisdictions, there have been a number of legislative and regulatory proposals and initiatives to change the health care system in ways that could affect our ability to sell our products profitably. Some of these proposed and implemented reforms could result in reduced reimbursement rates for our potential products, which would adversely affect our business strategy, operations and financial results. For example, in March 2010, President Obama signed into law a legislative overhaul of the U.S. healthcare system, known as the Patient Protection and Affordable Care Act of 2010, as amended by the Healthcare and Education Affordability Reconciliation Act of 2010, which we refer to as the PPACA. This legislation may have far reaching consequences for life science companies like us. As a result of this new legislation, substantial changes could be made to the current system for paying for healthcare in the United States, including changes made in order to extend medical benefits to those who currently lack insurance coverage. Extending coverage to a large population could substantially change the structure of the health insurance system and the methodology for reimbursing medical services, drugs and devices. These structural changes could entail modifications to the existing system of private payors and government programs, such as Medicare and Medicaid, creation of a government-sponsored healthcare insurance source, or some combination of both, as well as other changes. Restructuring the coverage of medical care in the United States could impact the reimbursement for prescribed drugs, biopharmaceuticals and medical devices. If reimbursement for our approved product candidates, if any, is substantially less that we expect in the future, or rebate obligations associated with them are substantially increased, our business could be materially and adversely impacted. A number of states have challenged the constitutionality of certain provisions of the Health Care Reform Law, and many of these court challenges are still pending final adjudication. Congress has also proposed a number of legislative initiatives, including possible repeal of the PPACA. At this time, it remains unclear whether there will be any changes made to the PPACA, whether to certain provisions or its entirety. In addition, some details regarding the implementation of the PPACA are yet to be determined, and at this time, the full effect that the PPACA would have on our business remains unclear. In addition, the Medicare Prescription Drug Improvement and Modernization Act of 2003, or MPDIMA, reformed the way Medicare will cover and reimburse for pharmaceutical products. This legislation could also decrease the coverage and price that we may receive for our approved product candidates, if any.

The cost-containment measures that healthcare providers are instituting and the results of healthcare reforms such as the PPACA and the MPDIMA may prevent us from maintaining prices for our approved product candidates that are sufficient for us to realize profits and may otherwise significantly harm our business, financial condition and operating results. In addition, to the extent that our approved product candidates, if any, are marketed outside of the United States, foreign government pricing controls and other regulations may prevent us from maintaining prices for such products that are sufficient for us to realize profits and may otherwise significantly harm our business, financial condition and operating results.

RISKS RELATED TO OUR COMMON STOCK

Our stock price may fluctuate significantly and the market price of our common stock could drop below the price paid.

The trading price of our common stock has been volatile and is likely to continue to be volatile in the future. For example, our stock traded within a range of a high price of $5.65 and a low price of $1.97 per share for the period January 1, 2011 through February 24, 2012. The stock market, particularly in recent years, has experienced significant volatility with respect to pharmaceutical and biotechnology company stocks. Prices for our stock will be determined in the marketplace and may be influenced by many factors, including:

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While we cannot predict the individual effect that these factors may have on the price of our common stock, these factors, either individually or in the aggregate, could result in significant variations in price during any given period of time.

In the past, securities class action litigation has often been instituted against companies following periods of volatility in their stock price. This type of litigation could result in substantial costs and divert our management’s attention and resources.

The limited liquidity for our common stock could affect an investor’s ability to sell our shares at a satisfactory price and makes the trading price of our common stock more volatile.

Our common stock is relatively illiquid. As of December 31, 2011, we had approximately 77.1 million shares of common stock outstanding. The average daily trading volume in our common stock during the prior 90 trading days ending on December 31, 2011 was approximately 383,000 shares. A more active public market for our common stock may not develop, which would continue to adversely affect the trading price and liquidity of our common stock. Moreover, common stock with a thin trading market may experience greater price fluctuation than the stock market as a whole. Without a large float, our common stock is less liquid than the stock of companies with broader public ownership and, as a result, the trading prices of our common stock may be more volatile.

Future sales of shares of our common stock, including shares issued upon the exercise of currently outstanding options and warrants or pursuant to our universal shelf registration statement could result in dilution to our stockholders and negatively affect our stock price.

Most of our outstanding common stock can be traded without restriction at any time. As such, sales of a substantial number of shares of our common stock in the public market could occur at any time. These sales, or the perception in the market that the holders of a large number of shares intend to sell such shares, could reduce the market price of our common stock. In addition, we have a significant number of shares that are subject to outstanding options and warrants and in the future we may issue additional options, warrants or other derivative securities convertible into our common stock. The exercise of any such options, warrants or other derivative securities, and the subsequent sale of the underlying common stock could cause a further decline in our stock price. These sales also might make it difficult for us to sell equity securities in the future at a time and at a price that we deem appropriate.

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Furthermore, as of December 31, 2011, we have outstanding warrants to purchase 1,610,818 shares of our common stock that contain antidilution adjustment provisions that will result in a decrease in the price and an increase in the number of shares of common stock issuable upon exercise of such warrants in the event of certain issuances of common stock by us at prices below $3.55 per share. For example, assuming that we issued and sold shares of common stock in a public offering at $3.00 per share, these warrants would become exercisable for an aggregate of 1,630,532 shares of our common stock, at an exercise price of $3.51 per share, which is equal to an aggregate of additional 19,714 shares as a result of the adjustment. To the extent that we are required to adjust the price and number of shares underlying these warrants as a result of this antidilution clause, and thereafter such warrants are exercised, additional shares of our common stock will be issued that will be eligible for resale in the public market, which could result in added dilution to our security holders and could also have an adverse effect on the market price of our common stock.

We currently have on file with the SEC a “universal” shelf registration statement which allows us to offer and sell registered common stock, preferred stock and warrants from time to time pursuant to one or more offerings at prices and terms to be determined at the time of sale. For example, in June 2011 we entered into an agreement with MLV pursuant to which, from time to time, we may offer and sell up to $20 million of the common stock that was registered on this shelf registration statement through MLV pursuant to one or more “at the market” offerings. In addition, with our prior written approval, MLV may also sell these shares of common stock by any other method permitted by law, including in privately negotiated transactions. Sales of substantial amounts of shares of our common stock or other securities under this registration statement could lower the market price of our common stock and impair our ability to raise capital through the sale of equity securities.

Compliance with Section 404 of the Sarbanes-Oxley Act of 2002 requires our management to devote substantial time to compliance initiatives, and if our independent registered public accounting firm is required to provide an attestation report on our internal controls but is unable to provide an unqualified attestation report, our stock price could be adversely affected.

Pursuant to Section 404 of the Sarbanes-Oxley Act of 2002, or Section 404, we are required to furnish a report by our management on the effectiveness of our internal control over financial reporting. The internal control report must contain (i) a statement of management’s responsibility for establishing and maintaining adequate internal control over financial reporting, (ii) a statement identifying the framework used by management to conduct the required evaluation of the effectiveness of our internal control over financial reporting and (iii) management’s assessment of the effectiveness of our internal control over financial reporting as of the end of our most recent fiscal year, including a statement as to whether or not internal control over financial reporting is effective.

To achieve compliance with Section 404 within the prescribed period, we will be engaged in a process to document and evaluate our internal control over financial reporting, which is both costly and challenging. In this regard, we will need to continue to dedicate internal resources, hire additional employees for our finance and audit functions, potentially engage outside consultants and adopt a detailed work plan to (i) assess and document the adequacy of internal control over financial reporting, (ii) continue steps to improve control processes where appropriate, (iii) validate through testing that controls are functioning as documented, and (iv) implement a continuous reporting and improvement process for internal control over financial reporting. In addition, in connection with the attestation process by our independent registered public accounting firm, if required, we may encounter problems or delays in completing the implementation of any requested improvements and receiving a favorable attestation. If we cannot favorably assess the effectiveness of our internal control over financial reporting, or if our independent registered public accounting firm is unable to provide an unqualified attestation report on our internal controls, investors could lose confidence in our financial information and our stock price could decline.

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If securities or industry analysts do not publish research or reports or publish unfavorable research or reports about our business, our stock price and trading volume could decline.

The trading market for our common stock will depend in part on the research and reports that securities or industry analysts publish about us, our business, our market or our competitors. There are currently nine research analysts that publish research coverage related to Curis. These securities and industry analysts may not maintain such coverage or we may fail to obtain research coverage by additional securities and industry analysts. If we do not maintain such existing coverage, and additional securities or industry analysts do not commence coverage of our company, the trading price for our stock may be negatively impacted. If one or more of the analysts who covers us downgrades our stock, our stock price would likely decline. If one or more of these analysts ceases to cover us or fails to regularly publish reports on us, interest in our stock could decrease, which could cause our stock price or trading volume to decline.

We do not intend to pay dividends on our common stock, and any return to investors will come, if at all, only from potential increases in the price of our common stock.

At the present time, we intend to use available funds to finance our operations. Accordingly, while payment of dividends rests within the discretion of our board of directors, no common stock dividends have been declared or paid by us and we have no intention of paying any common stock dividends in the foreseeable future.

Insiders have substantial influence over us and could delay or prevent a change in corporate control.

As of December 31, 2011, we believe that our directors, executive officers and principal stockholders, together with their affiliates, owned, in the aggregate, approximately 31% of our outstanding common stock. As a result, these stockholders, if acting together, will be able to exert influence over the management and affairs of our company and over matters requiring stockholder approval, including the election of directors and approval of significant corporate transactions. This concentration of ownership could harm the market price of our common stock by:

We have anti-takeover defenses that could delay or prevent an acquisition that our stockholders may consider favorable and the market price of our common stock may be lower as a result.

Provisions of our certificate of incorporation, our bylaws and Delaware law may have the effect of deterring unsolicited takeovers or delaying or preventing changes in control of our management, including transactions in which our stockholders might otherwise receive a premium for their shares over then current market prices. In addition, these provisions may limit the ability of stockholders to approve transactions that they may deem to be in their best interest. For example, we have divided our board of directors into three classes that serve staggered three-year terms, we may issue shares of our authorized “blank check” preferred stock and our stockholders are limited in their ability to call special stockholder meetings.

In addition, we are subject to the anti-takeover provisions of Section 203 of the Delaware General Corporation Law, which prohibits a publicly-held Delaware corporation from engaging in a business combination with an interested stockholder, generally a person which together with its affiliates owns, or within the last three years has owned, 15% of our voting stock, for a period of three years after the date of the transaction in which the person became an interested stockholder, unless the business combination is approved in a prescribed manner. These provisions could discourage, delay or prevent a change in control transaction.

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None.

We currently lease a facility for our administrative, research and development requirements located at 4 Maguire Road in Lexington, Massachusetts consisting of 24,529 square feet pursuant to a lease that expires February 2018. We believe that our existing facility will be suitable and adequate to meet our needs for the foreseeable future.

We are currently not a party to any material legal proceedings.

Not applicable.

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PART II

(a) Market Information.    Our common stock is traded on the NASDAQ Global Market under the trading symbol “CRIS.” The following table sets forth, for the fiscal periods indicated, the high and low sales prices per share of our common stock as reported on the NASDAQ Global Market:

(b) Holders.    On February 24, 2012, the last reported sale price of our common stock on the NASDAQ Global Market was $4.50 and there were 268 holders of record of our common stock. The number of record holders may not be representative of the number of beneficial owners because many of the shares of our common stock are held by depositories, brokers or other nominees.

(c) Dividends.    We have never declared or paid any cash dividends on our common stock. We currently intend to retain earnings, if any, to support our business strategy and do not anticipate paying cash dividends in the foreseeable future. Payment of future dividends, if any, will be at the sole discretion of our board of directors after taking into account various factors, including our financial condition, operating results, capital requirements and any plans for expansion.

(d) Issuer Purchases of Equity Securities.    We did not make any purchases of our shares of common stock in 2011.

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(e) Performance Graph.    The graph below compares the cumulative total stockholder return on our common stock for the period from December 31, 2006 through December 31, 2011, with the cumulative total return on (i) NASDAQ Pharmaceutical Index , (ii) NASDAQ Composite Index and (iii) NASDAQ Biotechnology Index. The comparison assumes investment of $100 on December 31, 2006 in our common stock and in each of the indices and, in each case, assumes reinvestment of all dividends.

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The selected consolidated financial data set forth below have been derived from our consolidated financial statements. These historical results are not necessarily indicative of results to be expected for any future period. You should read the data set forth below in conjunction with “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the consolidated financial statements and related notes included elsewhere in this report.

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The following discussion and analysis of financial condition and results of operations should be read together with “Selected Financial Data,” and our financial statements and accompanying notes appearing elsewhere in this annual report on Form 10-K. This discussion contains forward-looking statements, based on current expectations and related to future events and our future financial performance, that involve risks and uncertainties. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of many important factors, including those set forth under Item 1A, “Risk Factors” and elsewhere in this report.

Overview

We are a drug discovery and development company that is committed to leveraging our innovative signaling pathway drug technologies in seeking to develop next generation network-targeted cancer therapies. We are building upon our experience in modulating signaling pathways, including the Hedgehog signaling pathway, in our effort to develop network-targeted cancer therapies. We conduct our research and development programs both internally and through strategic collaborations.

Hedgehog Pathway Inhibitor Program (Erivedge™)

Erivedge™ (vismodegib) capsule. Our most advanced program is our Hedgehog pathway inhibitor program under collaboration with Genentech, Inc., a member of the Roche Group. The lead drug candidate being developed under this program is Erivedge, a first-in-class orally-administered small molecule Hedgehog pathway inhibitor, which is also referred to as vismodegib, GDC-0449 and RG3616. Erivedge is designed to selectively inhibit signaling in the Hedgehog pathway by targeting a protein called Smoothened. The Hedgehog signaling pathway plays an important role in regulating proper growth and development in the early stages of life and becomes less active in adults. However, mutations in the pathway that reactivate Hedgehog signaling are seen in certain cancers, including basal cell carcinoma, or BCC. Abnormal signaling in the Hedgehog pathway is implicated in over 90% of BCC cases.

In January 2012, Erivedge was approved by the U.S. Food and Drug Administration, or FDA, as the first and only FDA-approved medicine for adults with advanced forms of basal cell carcinoma that has spread to other parts of the body or that has come back after surgery or that their healthcare provider decides cannot be treated with surgery or radiation. It is not known if Erivedge is safe and effective in children. We earned a $10,000,000 milestone payment from Genentech as a result of the FDA’s approval of Erivedge in this indication and we are also entitled to receive royalties on future sales of the product. During the fourth quarter of 2011, we received a total of $14,000,000 in milestone payments from Genentech relating to the FDA’s acceptance of Genentech’s New Drug Application, or NDA, for Erivedge and the European Medicines Agency’s, or EMA’s, acceptance for review of a Marketing Authorization Application, or MAA for Erivedge, that was submitted by Roche in December 2011. The Genentech NDA and Roche MAA applications were based on positive clinical data from ERIVANCE BCC/SHH4476g, a pivotal phase II study of Erivedge in patients with advanced BCC. We will receive an additional milestone payment if Erivedge also receives EMA marketing authorization, as well as royalties on any future sales in this territory.

Genentech is also conducting a separate phase II clinical trial of Erivedge in patients with operable nodular basal cell carcinoma, which is a less severe form of the disease and accounts for a significant percentage of the approximately two million BCCs diagnosed annually in the United States. We anticipate that the study will be completed during early 2013.

In addition to the BCC clinical trials being conducted directly by Genentech and Roche, Erivedge is also currently being tested in other cancers in trials under collaborative agreements between Genentech and either third-party investigators or the U.S. National Cancer Institute, or NCI.

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Network-Targeted Cancer Programs

Our internal drug development efforts are focused on our network-targeted cancer programs, in which we are seeking to design single novel small molecule drug candidates that inhibit multiple signaling pathways that are believed to play roles in cancer cell proliferation. We refer to this approach as cancer network disruption. We believe that our approach of targeting multiple nodes in cancer signaling pathway networks may provide a better therapeutic effect than many of the cancer drugs currently marketed or in development since our drug candidates are being designed to disrupt multiple targets in the cancer network environment as compared to most other cancer drugs which are designed to disrupt only one target.

CUDC-101.    Our lead candidate from these programs is CUDC-101, a first-in-class small molecule compound designed to simultaneously target histone deacetylase, or HDAC, epidermal growth factor receptor, or EGFR, and human epidermal growth factor receptor 2, or HER2, all of which are validated cancer targets. A significant amount of our capital resources are focused on the ongoing clinical development of this molecule. To date, we have completed a phase I dose escalation clinical trial of CUDC-101 in 25 patients with advanced, refractory solid tumors and we have completed enrollment in a phase I expansion trial to test CUDC-101 in 46 patients with specific tumor types, including breast, gastric, head and neck, liver and non-small cell lung cancers. The phase I expansion trial is designed as an open-label study in which patients are treated with CUDC-101 at the maximum tolerated dose, which was determined in the phase I dose escalation study to be 275 milligrams per meter². The primary objectives of this study are to compare the safety and tolerability of CUDC-101 in subjects with these specific advanced solid tumors when the drug is administered via one-hour intravenous infusion either on a five days per week schedule (one week on/one week off) or on a three days per week schedule (three weeks on/one week off).

During the second quarter of 2011, we initiated a phase I clinical trial of CUDC-101 in locally advanced head and neck cancer patients whose cancer is human papilloma virus, or HPV, negative. We have treated four patients in this trial as of February 24, 2012. The primary objectives of this study are to evaluate the safety and tolerability of CUDC-101 when administered in combination with the current standard-of-care of cisplatin, a chemotherapeutic drug, and radiation. Upon determination of the maximum tolerated dose and assuming the otherwise successful completion of the phase I trial, we intend to conduct a randomized phase II two-arm clinical trial in which head and neck cancer patients will receive cisplatin and radiation plus or minus CUDC-101. The phase II study would seek to evaluate whether the addition of CUDC-101 can improve the efficacy of cisplatin and radiation therapy in this patient population. We currently estimate initiating this phase II study in the first half of 2013.

We are also working on an oral formulation of CUDC-101, which we believe has the potential to make CUDC-101 more competitive in certain cancers such as non-small cell lung cancer or in other cancers where there are investigational or competing commercially available molecules that are orally administered. Pending the successful completion of ongoing formulation and preclinical development work, we intend to begin a phase I study of an oral formulation of CUDC-101 in the second half of 2012.

CUDC-907.    In January 2011, we selected development candidate CUDC-907, an orally bioavailable, network-targeted small molecule that is designed to inhibit HDAC and phosphatidylinositol-3-kinase, or PI3K. Our scientists are developing CUDC-907 based on published and internally generated data demonstrating that HDAC and PI3K inhibitors have synergistic interaction in certain preclinical cancer models. We believe that this synergistic mechanism of cancer signaling network disruption, which demonstrated efficacy and a favorable safety profile in a number of preclinical xenograft models, could translate into clinical advantages over single agents.

In November 2011, we entered into an agreement under which The Leukemia & Lymphoma Society, or LLS, will provide a portion of the funding of the development of CUDC-907 if we succeed in advancing this development candidate into a clinical trial for patients with B-cell lymphoma and multiple myeloma. Pending the successful completion of ongoing formulation and preclinical development work, we expect to file an IND with the FDA to test an oral formulation of CUDC-907 during the second half of 2012.

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In addition to our development-stage programs, we continue to progress additional proprietary preclinical research programs and expect that we will select additional small molecule inhibitors from our preclinical portfolio in the future.

Hsp90 Program

Debio 0932.    Our heat shock protein 90, or Hsp90, program is being developed by Debiopharm, a Swiss pharmaceutical development company, under an August 2009 license agreement between Curis and Debiopharm. The lead molecule under this license collaboration was designated Debio 0932 by Debiopharm. In April 2010, Debiopharm treated the first patient in a phase I clinical trial to evaluate the safety of Debio 0932 in patients suffering from advanced solid tumors. In 2011, Debiopharm successfully advanced Debio 0932 through the dose escalation portion of the phase I study. Debio 0932 was generally well tolerated, with no evidence of ocular or liver toxicity, and showed promising signs of efficacy in patients with advanced solid tumors in this study. Debiopharm has indicated that it expects to present phase I data from this phase I study at a medical conference during the first half of 2012.

Debiopharm advanced Debio 0932 into the phase Ib expansion portion of the study in the beginning of 2012. Debiopharm expects to treat approximately 30 patients in this study, with the primary objectives of the phase Ib study, an expansion cohort of solid tumor patients, will be to further assess the safety profile, pharmacokinetics and pharmacodynamics of Debio 0932 at the recommended dose level of 1000mg daily that was established in the dose escalation portion of the Phase I clinical trial, and to make a preliminary assessment of anti-tumor activity in patients with advanced solid tumors, including patients with non-small cell lung cancer.

Debiopharm has also indicated that it expects to initiate a combination Phase I/II study in non-small cell lung cancer patients in the second quarter of 2012. We are eligible for our next milestone payment under our license agreement if and when Debiopharm treats its fifth patient in a phase II clinical trial, assuming that Debiopharm advances Debio 0932 into phase II clinical testing. We currently anticipate that phase II testing could commence in the first half of 2013.

Liquidity

Since our inception, we have funded our operations primarily through license fees, contingent cash payments, research and development funding from our corporate collaborators, the private and public placement of our equity securities, debt financings and the monetization of certain royalty rights. We have never been profitable and have an accumulated deficit of $732,088,000 as of December 31, 2011. We expect to incur significant operating losses for the next several years as we devote substantially all of our resources to our research and development programs. We will need to generate significant revenues to achieve profitability and do not expect to achieve profitability in the foreseeable future, if at all. We anticipate that existing capital resources as of December 31, 2011 should enable us to maintain current and planned operations into the second half of 2013. We believe that near term key drivers to our success will include:

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In the longer term, a key driver to our success will be our ability, and the ability of any current or future collaborator or licensee, to successfully commercialize drugs based upon our proprietary technologies.

Collaboration Agreements

We are currently a party to a June 2003 collaboration with Genentech relating to our Hedgehog pathway inhibitor technologies, and an August 2009 license agreement with Debiopharm relating to our Hsp90 inhibitor technology. Our past and current collaborations have generally provided for research, development and commercialization programs to be wholly or majority-funded by our collaborators and provide us with the opportunity to receive additional contingent cash payments if specified development and regulatory approval objectives are achieved, as well as royalty payments upon the successful commercialization of any products based upon the collaborations. We are currently not receiving any research funding and we do not expect to receive such funding in the future from Genentech or Debiopharm under our current agreements with these parties. Under our collaborations with Genentech, we currently expect to incur only costs related to the maintenance of licenses, including sublicense payments due upon milestone payments and any royalties we receive, as well as patent-related expenses. As a result of our licensing agreements with various universities, we are also obligated to make payments to these university licensors when we receive certain payments from Genentech. As of December 31, 2011, we have incurred an aggregate of approximately $1,640,000 related to ongoing agreements, of which $1,600,000 relates to payments that we received from Genentech. As we receive additional milestone payments from Genentech upon FDA approval of Erivedge obtained in January 2012, and EMA approval, if achieved, we will be obligated to pay 5% in additional sublicense fees to these licensors, as well as a total of 5% of any royalties received from the sale of Erivedge. We do not expect to incur any material costs related to our Hsp90 technologies under development by Debiopharm under our August 2009 license agreement with Debiopharm.

Our current collaboration agreements are summarized as follows:

Genentech Hedgehog Pathway Inhibitor Collaboration.    Under the terms of the June 2003 agreement with Genentech, we granted Genentech an exclusive, global, royalty-bearing license, with the right to sublicense, to make, use, sell and import small molecule and antibody Hedgehog pathway inhibitors. In November 2008, Genentech granted a sublicense to F. Hoffmann-LaRoche, Ltd (Roche) for non-U.S. rights to GDC-0449. Roche received this sublicense pursuant to an agreement between Genentech and Roche under which Genentech granted Roche an option to obtain a license to commercialize certain Genentech products in non-U.S. markets. In February 2010, we announced that Chugai Pharmaceutical Co., Ltd. had exercised its right of first refusal for the development and commercialization in Japan of GDC-0449 under an existing agreement with Roche. Genentech and Roche have primary responsibility for worldwide clinical development, regulatory affairs, manufacturing and supply, formulation and sales and marketing. We are not a party to this agreement between Genentech and Roche but we are eligible to receive cash payments for regulatory filing and approval objectives achieved and future royalties on products developed outside of the U.S., if any, under our June 2003 collaboration agreement with Genentech.

The lead drug candidate being developed under this program is Erivedge, a first-in-class orally-administered small molecule Hedgehog pathway inhibitor that is the first and only FDA-approved medicine for adults with advanced forms of basal cell carcinoma. Genentech and Roche are responsible for worldwide clinical development, regulatory affairs, manufacturing and supply, formulation and sales and marketing of Erivedge. We are eligible to receive cash payments for regulatory filing and approval objectives achieved and future royalties on products developed outside of the U.S., if any, under our June 2003 collaboration agreement with Genentech. We are eligible to receive up to $115,000,000 in contingent cash payments under the terms of our June 2003 collaboration for the development of Erivedge or another small molecule, assuming the successful achievement by Genentech and Roche of specified clinical development and regulatory objectives. We have received $42,000,000 of this amount including the $10,000,000 payment that we earned in January 2012. We are also eligible to receive royalties on sales of any Hedgehog pathway inhibitor products that are successfully

commercialized by Genentech and Roche. For Erivedge, we are entitled to a mid-to-high single digit royalty, which escalates within this range with increasing product sales. In certain specified circumstances, the royalty rate applicable to Erivedge may be decreased to a low-to-mid single digit royalty.

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Debiopharm Hsp90 Collaboration.    In August 2009, we granted a worldwide, exclusive royalty-bearing license to our Hsp90 inhibitor technology to Debiopharm, a Swiss pharmaceutical development company. The lead molecule under this license collaboration was designated Debio 0932 by Debiopharm. Debiopharm has assumed all future development responsibility and costs related to the development, registration and commercialization of products under the agreement. As part of the consideration under the agreement, Debiopharm paid us an up-front license fee of $2,000,000, and we received $11,000,000 during 2010 in contingent payments upon Debiopharm’s successful achievement of clinical objectives, including the approval from French regulatory authorities of Debiopharm’s clinical trial application, or CTA, to begin phase I clinical trials and the treatment of the fifth patient in this trial. We are also eligible to receive royalties if any products under the license agreement are successfully developed and commercialized. For net sales of Debio 0932 that are made directly by Debiopharm, we are entitled to a high single digit to low double digit royalty, which escalates within this range with increasing product sales. In certain specified circumstances, the royalty rate applicable to Debio 0932 may be reduced. We believe that it is more likely that Debiopharm will sublicense Debio 0932 following its further development, and in this case we are entitled to a share of royalties that Debiopharm receives from such sublicensee.

Financial Operations Overview

General.    Our future operating results will largely depend on the magnitude of payments from our current and potential future corporate collaborators and the progress of drug candidates currently in our research and development pipeline. The results of our operations will vary significantly from year to year and quarter to quarter and depend on, among other factors, the timing of our entry into new collaborations, if any, the timing of the receipt of payments, if any, from new or existing collaborators and the cost and outcome of any preclinical development or clinical trials then being conducted. We anticipate that existing capital resources as of December 31, 2011 should enable us to maintain current and planned operations into the second half of 2013. Our ability to continue funding our planned operations into and beyond the second half of 2013 is dependent on future contingent payments that we may receive from Debiopharm, Genentech, or the LLS upon the achievement of development and regulatory approval objectives, our ability to manage our expenses and our ability to raise additional funds through additional corporate collaborations, equity or debt financings, or from other sources of financing.

We expect to end 2012 with cash, cash equivalents and marketable securities of $23 million to $27 million, excluding any potential payments from existing or new collaborators. We expect that our expenses associated with the clinical development of CUDC-101 will increase as we continue to treat patients in our phase I trial in head and neck cancers and initiation of additional trials for CUDC-101 and CUDC-907, resulting in an increase in our research and development expenses for future periods as compared to prior years. We expect that research and development expenses for the year ended December 31, 2012 will be $16 million to $20 million and that general and administrative expenses will be $10 million to $12 million. These expense estimates include $800,000 and $2.5 million of stock-based compensation expense for research and development and general and administrative expense, respectively, which includes employee and director equity grants issued in January 2012. Actual stock-based compensation expense for fiscal 2012 may be higher as the result of our issuance of additional awards as part of our planned compensation programs, consistent with past practices.

Revenue.    We do not expect to generate any revenue from our direct sale of products for several years, if ever. Substantially all of our revenues to date have been derived from license fees, research and development payments, and other amounts that we have received from our strategic collaborators and licensees. For the year ended December 31, 2011, Genentech accounted for $14,388,000, or 97%, of our total revenue. We have not recognized any royalty revenue to date but we expect that we will recognize royalties attributed to the sale of Erivedge in 2012.

We could receive additional milestone payments from our collaborators Genentech and Debiopharm, provided the respective programs meet contractually-specified development and regulatory objectives. For example, we earned a $10,000,000 milestone payment from Genentech in January 2012 upon FDA approval of Erivedge. In addition, Erivedge is currently being reviewed for potential marketing approval by the EMA in European territories. We are eligible to receive additional milestone revenue should Erivedge receive approval by the EMA, and we are also eligible to receive royalties on net sales of Erivedge.

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We currently receive no research funding for our programs under our collaborations with Genentech and Debiopharm and we do not expect to receive such funding in the future under these collaborations. Accordingly, our only source of revenues and/or cash flows from operations for the foreseeable future will be up-front license payments and funded research and development that we may receive under new collaboration agreements, if any, contingent cash payments for the achievement of clinical development and regulatory objectives, if any are met, under new collaborations or our existing collaborations with Genentech and Debiopharm and royalty payments that are contingent upon the successful commercialization of any products based upon these collaborations. Our ability to enter into new collaborations and our receipt of additional payments under our existing collaborations with Genentech and Debiopharm cannot be assured, nor can we predict the timing of any such arrangements or payments, as the case may be.

Research and Development.    Research and development expense consists of costs incurred to discover, research and develop our drug candidates. These expenses consist primarily of: (1) salaries and related expenses for personnel including stock-based compensation expense; (2) outside service costs including clinical research organizations, medicinal chemistry and sublicense payments; and (3) the costs of supplies and reagents, consulting, and occupancy and depreciation charges. We expense research and development costs as incurred. We are currently incurring only nominal research and development expenses under our Hedgehog pathway inhibitor collaboration with Genentech related to the maintenance of third-party licenses to certain background technologies. For each contingent payment, if any, received under the Hedgehog pathway inhibitor collaboration, we would be obligated to make payments to certain third-party licensors and recognize the related expense.

Our research and development programs, both internal and under collaboration, are summarized in the following table:

In the chart above, “FDA approval” means that Genentech’s NDA was approved by the FDA for commercialization of Erivedge in the United States. “MAA review” means that Roche has filed an MAA with the EMA, and the EMA has accepted and is currently reviewing the application for potential approval to commercialize Erivedge in Europe. “Phase II” means that Genentech is currently treating human patients in a phase II clinical trial, the primary objective of which is a therapeutic response in the patient population. “Phase I expansion” means that we are currently treating human patients with specific tumor types in an extension of our phase I dose escalation trial, at the maximum tolerated dose from such trial, the principal purpose of which is to evaluate the safety and tolerability of the compound being tested. “Phase Ib” means that Debiopharm is further assessing the safety profile, pharmacokinetics and pharmacodynamics of Debio 0932 at the recommended phase II dose level, and seeking to make a preliminary assessment of anti-tumor activity in patients with advanced solid tumors. “Phase I” means that we are currently treating human patients in separate phase I clinical trials with CUDC-101, the principal purpose of which is to evaluate the safety and tolerability of the compound being tested. “Development candidate” means that we have selected a single lead candidate for potential future clinical

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development and are seeking to complete the relevant safety, toxicology, and other studies required to submit an IND application with the FDA seeking to commence a phase I clinical trial based on our testing in several preclinical models of human disease of various compounds from a particular compound class. “Preclinical” means that we are seeking to obtain evidence of therapeutic efficacy and safety in preclinical models of human disease of one or more compounds within a particular class of drug candidates.

Because of the early stages of development of these programs, our ability and that of our collaborators and licensees to successfully complete preclinical studies and clinical trials of these drug candidates, and the timing of completion of such programs, is highly uncertain. There are numerous risks and uncertainties associated with developing drugs which may affect our and our collaborators’ future results, including:

We cannot reasonably estimate or know the nature, timing and estimated costs of the efforts necessary to complete the development of, or the period in which material net cash inflows are expected to commence from any of our drug candidates. Any failure to complete the development of our drug candidates in a timely manner could have a material adverse effect on our operations, financial position and liquidity.

A further discussion of some of the risks and uncertainties associated with completing our research and development programs on schedule, or at all, and some consequences of failing to do so, are set forth above in “Part I, Item 1A—Risk Factors.”

General and Administrative.    General and administrative expense consists primarily of salaries, stock-based compensation expense and other related costs for personnel in executive, finance, accounting, business development, legal, information technology, corporate communications and human resource functions. Other costs include facility costs not otherwise included in research and development expense, insurance, and professional fees for legal, patent and accounting services. Patent costs include certain patents covered under collaborations, a portion of which is reimbursed by collaborators and a portion of which is borne by us. We expect that our general and administration expenses will increase in future periods as patent costs related to our Hedgehog pathway inhibitor collaboration with Genentech increase as well as an increase in our non-cash stock-based compensation expense in 2012 as compared to prior periods.

Critical Accounting Policies and Estimates

The preparation of our consolidated financial statements in conformity with accounting principles generally accepted in the United States requires that we make estimates and assumptions that affect the reported amounts and disclosure of certain assets and liabilities at our balance sheet date. Such estimates and judgments include the carrying value of property and equipment and intangible assets, revenue recognition, the value of certain liabilities, including our warrant liability, and stock-based compensation. We base our estimates on historical experience and on various other factors that we believe to be appropriate under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

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While our significant accounting policies are more fully described in our consolidated financial statements, we believe that the following accounting policies are critical to understanding the judgments and estimates we use in preparing our financial statements:

Revenue Recognition

Our business strategy includes entering into collaborative license and development agreements with biotechnology and pharmaceutical companies for the development and commercialization of our product candidates. The terms of the agreements typically include non-refundable license fees, funding of research and development, payments based upon achievement of clinical development milestones and royalties on product sales. We follow the provisions of the Financial Accounting Standards Board, or FASB, Codification Topic 605, Revenue Recognition.

License Fees and Multiple Element Arrangements.

In January 2010, we adopted a new U.S. GAAP accounting standard which amends existing revenue recognition accounting guidance to provide accounting principles and application guidance on whether multiple deliverables exist, how the arrangement should be separated, and the consideration allocated. This new guidance eliminates the requirement to establish objective evidence of fair value of undelivered products and services and instead provides for separate revenue recognition based upon management’s estimate of the selling price for an undelivered item when there is no vendor-specific objective evidence or third-party evidence to determine the fair value of that undelivered item. Because we did not enter into any new multiple element arrangements or modify our existing collaborations during the year ended December 31, 2011, recognition models used to derive our revenues for the year ended December 31, 2011 reflect the superseded guidance and the adoption of the new standard will be implemented on a prospective basis for new or materially modified arrangements.

For multiple element arrangements, including license agreements, entered into prior to January 1, 2010, guidance required that the fair value of the undelivered item be the price of the item either sold in a separate transaction between unrelated third parties or the price charged for each item when the item is sold separately by the vendor. This was difficult to determine when the product was not individually sold because of its unique features. Under this guidance, if the fair value of all of the undelivered elements in the arrangement was not determinable, then revenue was deferred until all of the items were delivered or fair value was determined.

Non-refundable license fees are recognized as revenue when we have a contractual right to receive such payment, the contract price is fixed or determinable, the collection of the resulting receivable is reasonably assured and we have no further performance obligations under the license agreement. Multiple element arrangements, such as license and development arrangements are analyzed to determine whether the deliverables, which often include a license and performance obligations such as research and steering committee services, can be separated or whether they must be accounted for as a single unit of accounting in accordance with U.S. generally accepted accounting principles, or GAAP. We recognize up-front license payments as revenue upon delivery of the license only if the license has stand-alone value and the fair value of the undelivered performance obligations, typically including research and/or steering committee services, can be determined. If the fair value of the undelivered performance obligations can be determined, such obligations would then be accounted for separately as performed. If the license is considered to either (i) not have stand-alone value or (ii) have stand-alone value but the fair value of any of the undelivered performance obligations cannot be determined, the arrangement would then be accounted for as a single unit of accounting and the license payments and payments for performance obligations are recognized as revenue over the estimated period of when the performance obligations are performed.

Whenever we determine that an arrangement should be accounted for as a single unit of accounting, we must determine the period over which the performance obligations will be performed and revenue will be recognized. Revenue will be recognized using either a relative performance or straight-line method. We recognize revenue using the relative performance method provided that we can reasonably estimate the level of

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effort required to complete our performance obligations under an arrangement and such performance obligations are provided on a best-efforts basis. Direct labor hours or full-time equivalents are typically used as the measure of performance. Revenue recognized under the relative performance method would be determined by multiplying the total payments under the contract, excluding royalties and payments contingent upon achievement of substantive milestones, by the ratio of level of effort incurred to date to estimated total level of effort required to complete our performance obligations under the arrangement. Revenue is limited to the lesser of the cumulative amount of payments received or the cumulative amount of revenue earned, as determined using the relative performance method, as of each reporting period.

If we cannot reasonably estimate the level of effort required to complete our performance obligations under an arrangement, the performance obligations are provided on a best-efforts basis and we can reasonably estimate when the performance obligation ceases or becomes inconsequential, then the total payments under the arrangement, excluding royalties and payments contingent upon achievement of substantive milestones, would be recognized as revenue on a straight-line basis over the period we expect to complete our performance obligations. Revenue is limited to the lesser of the cumulative amount of payments received or the cumulative amount of revenue earned, as determined using the straight-line basis, as of the period ending date.

If we cannot reasonably estimate when our performance obligation either ceases or becomes inconsequential and perfunctory, then revenue is deferred until we can reasonably estimate when the performance obligation ceases or becomes inconsequential and perfunctory. Revenue is then recognized over the remaining estimated period of performance.

In addition, if we are involved in a steering committee as part of a multiple element arrangement that is accounted for as a single unit of accounting, we assess whether our involvement constitutes a performance obligation or a right to participate. Steering committee services that are not inconsequential or perfunctory and that are determined to be performance obligations are combined with other research services or performance obligations required under an arrangement, if any, in determining the level of effort required in an arrangement and the period over which we expect to complete our aggregate performance obligations.

Substantive Milestone Payments.    Our collaboration agreements may also contain substantive milestone payments. Collaboration agreements that contain substantive milestone payments are recognized upon achievement of the milestone only if the milestone meets all of the following criteria:

Determination as to whether a payment meets the aforementioned conditions involves management’s judgment. If any of these conditions are not met, the resulting payment would not be considered a substantive milestone, and the resulting payment would be considered part of the consideration for the single unit of accounting and be recognized as revenue as such performance obligations are performed under either the relative performance or straight-line methods, as applicable, and in accordance with these policies as described above. In addition, the determination that one such payment was not a substantive milestone could prevent us from concluding that subsequent milestone payments were substantive milestones and, as a result, any additional milestone payments could also be considered part of the consideration for the single unit of accounting and

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would be recognized as revenue as such performance obligations are performed under either the relative performance or straight-line methods, as applicable. Milestones that are tied to regulatory approval are not considered probable of being achieved until such approval is received. Milestones tied to counter-party performance are not included in our revenue model until the performance conditions are met.

Reimbursement of Costs.    Reimbursement of research and development costs by third party collaborators has been historically recognized as revenue provided the provisions of FASB Codification Topic 605-45, Revenue Recognition, Principal Agent Consideration, are met, the amounts are determinable, and collection of the related receivable is reasonably assured.

Royalty Revenue.    We expect to recognize royalty revenue upon the sale of the related products, provided that the royalty amounts are fixed or determinable, collection of the related receivable is reasonably assured and we have no remaining performance obligations under the arrangement. If royalties are received when we have remaining performance obligations, we expect to attribute the royalty payments to the services being provided under the arrangement and therefore recognize such royalty payments as such performance obligations are performed under either the relative performance or straight line methods, as applicable, and in accordance with these policies as described above. We have not recognized any royalty revenue to date but we expect that we will recognize royalties attributed to the sale of Erivedge in 2012.

Deferred Revenue.    Amounts received prior to satisfying the above revenue recognition criteria are recorded as deferred revenue in the accompanying consolidated balance sheets. Significant judgments are required in the application of revenue recognition guidance. For example, in connection with our existing and former collaboration agreements, we have historically recorded on our balance sheet short- and long-term deferred revenue based on our best estimate of when such revenue would be recognized. Short-term deferred revenue would consist of amounts that are expected to be recognized as revenue, or applied against future co-development costs, within the next fiscal year. Amounts that we expect will not be recognized in the next fiscal year would be classified as long-term deferred revenue. However, this estimate would be based on our operating plan as of the balance sheet date and on our estimated performance periods under the collaboration in which we have recorded deferred revenues. If our operating plan or our estimated performance period would change, we could recognize a different amount of deferred revenue over the reporting period.

With respect to each of the foregoing areas of revenue recognition, we exercise significant judgment in determining whether an arrangement contains multiple elements, and, if so, how much revenue is allocable to each element. In addition, we exercise our judgment in determining when our significant obligations have been met under such agreements and the specific time periods over which we recognized revenue, such as non-refundable, up-front license fees. To the extent that actual facts and circumstances differ from our initial judgments, our revenue recognition with respect to such transactions would change accordingly and any such change could affect our reported operating results. To the extent that actual facts and circumstances differ from our initial judgments, our revenue recognition with respect to such arrangement would change accordingly and any such change could affect our reported financial results.

Stock-based Compensation

Effective January 1, 2006, we adopted Statement of Financial Accounting Standards, or SFAS, No. 123 (revised 2004), Share-Based Payment, which generally requires that such transactions be accounted for using a fair-value-based method and is now referred to as FASB Codification Topic 718, Compensation – Stock Compensation.

We have recorded employee and director stock-based compensation expense of $1,642,000, $1,979,000 and $1,750,000 for the years ended December 31, 2011, 2010 and 2009, respectively. We estimate that we will record approximately $3,300,000, in stock-based compensation expense in 2012. We have granted and expect that we may grant additional options in 2012 that could increase the amount of stock-based compensation ultimately

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recognized. The amount of the incremental employee stock-based compensation expense attributable to 2012 employee stock options to be granted will depend primarily on the number of stock options granted, the fair market value of our common stock at the respective grant dates, and the specific terms of the stock options.

We measure compensation cost for share-based compensation at fair value, including estimated forfeitures, and recognize the expense as compensation expense over the period that the recipient is required to provide service in exchange for the award, which generally is the vesting period. We use the Black-Scholes option pricing model to measure the fair value of stock options. This model requires significant estimates related to the award’s expected life and future stock price volatility of the underlying equity security. In determining the amount of expense to be recorded, we also are required to estimate forfeiture rates for awards, based on the probability that employees will complete the required service period. We estimate the forfeiture rate based on historical experience. If actual forfeitures differ significantly from our estimates, additional adjustments to compensation expense may be required in future periods. Ultimately, the actual expense recognized over the vesting period will only be for those shares that vest.

Fair Value Measurements

Effective January 1, 2008, we adopted the provisions of SFAS No. 157, Fair Value Measurements for our financial assets and financial liabilities, which is now referred to as FASB Codification Topic 820, Fair Value Measurements and Disclosures. Topic 820 provides a framework for measuring fair value under GAAP and requires expanded disclosures regarding fair value measurements. GAAP defines fair value 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. Market participants are buyers and sellers in the principal market that are (i) independent, (ii) knowledgeable, (iii) able to transact, and (iv) willing to transact.

GAAP requires the use of valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets and liabilities. The income approach uses valuation techniques to convert future amounts, such as cash flows or earnings, to a single present amount on a discounted basis. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset (replacement cost). Valuation techniques should be consistently applied. GAAP also establishes a fair value hierarchy which requires an entity to maximize the use of observable inputs, where available, and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value:

Our cash equivalents and marketable securities have been classified as either Level 1 or Level 2 assets. We do not hold any asset-backed or auction rate securities. Short-term accounts receivable and accounts payable are reflected in the consolidated financial statements at net realizable value, which approximates fair value due to the short-term nature of these instruments.

In 2010, we completed a registered direct offering in which we issued warrants to purchase shares of our common stock. The warrants include certain protective features for the benefit of the warrantholder, including an exercise price adjustment clause and a possible cash-settlement option in the event of a change of control until the later to occur of (i) two years from the date of original issuance of the warrant, or January 27, 2012 and

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(ii) the date upon which Genentech or Roche submits a new drug application (NDA) for GDC-0449 (Erivedge) which occurred in September 2010. Due to these terms, the warrants were deemed to be a liability. We estimate the fair value of the warrants using a Black-Scholes option pricing model under various probability-weighted outcomes which take into consideration the protective, but limited, cash-settlement feature of the warrants. In using this model, the fair value is determined by applying Level 3 inputs, which have included assumptions around the estimated future stock price of our common stock and varying probabilities that certain events will occur. Significant increases or decreases in any of these assumptions would materially impact the fair value of the warrants and our financial statements. The warrants will be revalued each reporting period with updated assumptions, and the resulting change in fair value of the warrant liability will be recognized in our financial statements.

While we believe our valuation methodologies are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date.

Long-lived Assets

Long-lived assets consist primarily of property and equipment and goodwill. Property and equipment is stated at cost and depreciated over the estimated useful lives of the related assets using the straight-line method. Determining the economic lives of property and equipment requires us to make significant judgments that can materially impact our operating results. If it were determined that the carrying value of our other long-lived assets might not be recoverable based upon the existence of one or more indicators of impairment, we would measure an impairment based on application of FASB Codification Topic 360-10-05, Impairment or Disposal of Long-Lived Assets.

We evaluate our goodwill for impairment at least annually or more frequently if an indicator of potential impairment exists. In performing our evaluations of impairment, we determine fair value using widely accepted valuation techniques, including discounted cash flows. These calculations contain uncertainties as they require us to make assumptions related to future cash flows, projected useful lives of assets and the appropriate discount rate to reflect the risk inherent in future cash flows. We must also make assumptions regarding industry economic factors and the profitability of future business strategies. If actual results are not consistent with our estimates and assumptions used in estimating future cash flows and asset fair values, we may be exposed to a material impairment charge. As a single reporting unit, we completed our annual goodwill impairment tests in December 2011, 2010 and 2009, and determined that as of those dates our fair value exceeded the carrying value of our net assets. Accordingly, no goodwill impairment was recognized in 2011, 2010 and 2009.

Our discussion of our critical accounting policies is not intended to be a comprehensive discussion of all of our accounting policies. In many cases, the accounting treatment of a particular transaction is specifically dictated by generally accepted accounting principles, with no need for management’s judgment in their application. There are also areas in which management’s judgment in selecting any available alternative would not produce a materially different result.

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Results of Operations (all amounts rounded to the nearest thousand)

Years Ended December 31, 2011 and 2010

Revenues

Total revenues are summarized as follows:

Total revenues decreased by $1,237,000, or 8%, for the year ended December 31, 2011 as compared to the prior year, primarily related to a decrease in our license fee revenues of $1,356,000. During the year ended December 31, 2011, we recognized $14,000,000 in license revenue for the achievement of FDA and EMA acceptances of Genentech’s NDA and MAA filings, respectively, related to Erivedge which is under collaboration with Genentech. During the year ended December 31, 2010, we recorded license fee revenues of $15,656,000, primarily comprised of an $11,000,000 contingent payment from Debiopharm upon the achievement of development milestones under our license agreement with Debiopharm as well as settlement proceeds of $4,000,000 that we received from Micromet pursuant to a settlement, mutual release and termination agreement that we entered into with Micromet in February 2010.

All potential future contingent payments under our Genentech and Debiopharm agreements are tied to clinical and regulatory objective milestones. Erivedge received FDA approval in January 2012 for which we earned a $10,000,000 contingent payment and will receive royalties on any sales. If Erivedge receives EMA marketing authorization, we will be entitled to receive an additional milestone payment as well as royalties on any future net sales. Because the settlement with Micromet discharged and terminated all future payment obligations that would have arisen under the June 2001 agreement, we do not expect to receive any additional revenues from Micromet.

Research and development revenues increased by $119,000, or 35%, for the year ended December 31, 2011 as compared to the prior year. Research and development revenues are limited to expenses that we incur under our collaborations, primarily Genentech, for which our collaborators are obligated to reimburse us.

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Operating Expenses

Research and development expenses are summarized as follows:

Our research and development expenses increased by $2,320,000, or 20%, for the year ended December 31, 2011, as compared to the prior year. The increase in research and development expenses is the result of a $962,000 increase in spending related to our CUDC-101 program, which primarily relates to outside services and clinical costs associated with several of our programs for CUDC-101, including our phase I expansion trial for which we completed patient dosing in October 2011, costs related to our phase I trial in locally advanced HPV- head and neck cancers and manufacturing and toxicology costs related to an oral formulation of CUDC-101. In addition, spending related to our CUDC-907 program increased $3,201,000 over the prior year period as a result of shifting resources from our other network-targeted cancer programs. Our 2011 spending on our other network-targeted cancer programs decreased by $2,633,000 when compared to 2010. CUDC-907 was selected as a development candidate in January 2011. During the year ended December 31, 2011, we also incurred expenses of $700,000 in sublicense payments that we made as a result of receiving $14,000,000 from Genentech during 2011 for the achievement of regulatory objectives related to Erivedge under our Hedgehog pathway inhibitor program. No such expenses were incurred under the Genentech collaboration during the year ended December 31, 2010.

We expect that a majority of our research and development expenses for the foreseeable future will be incurred in support of our efforts to advance CUDC-101, CUDC-907 and our other targeted cancer programs. In addition, we will be obligated to pay additional sublicense fees for milestone payments received upon achievement of certain regulatory objectives and royalty payments on net sales of Erivedge in the U.S. that we receive from Genentech.

General and administrative expenses are summarized as follows:

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General and administrative expenses decreased by $1,993,000, or 19%, for the year ended December 31, 2011, as compared to the prior year. This decrease was related to a reduction in spending in several areas, primarily for legal services. During the year ended December 31, 2010, we incurred approximately $1,526,000 in expenses related to an arbitration proceeding that we filed against our former collaborator that we did not incur in the current period. In addition, legal costs associated with various matters decreased $212,000 from the prior year period. Offsetting these decreases in legal spending, our patent-related costs increased $323,000 in the year ended December 31, 2011 as compared to the prior year period primarily related to fees for foreign patent, opposition and interference filings. Consulting and professional services decreased $238,000 for the year ended December 31, 2011, as compared to the prior year. During the year ended December 31, 2010, we incurred consulting and professional services specifically related to business development efforts used to facilitate the licensing agreement with Debiopharm due upon receipt of the milestone payments we received in 2010 that were not incurred in 2011.

Personnel costs decreased $176,000 primarily resulting from discretionary bonuses to our executive officers, the majority of which was paid upon receipt of contingent payments received from Debiopharm in 2010. Stock-based compensation also decreased $256,000 from the prior year primarily related to vesting of certain performance-based stock options in the first quarter of 2010 that did not occur during 2011. Offsetting these decreases, our allocated occupancy costs increased $79,000 for the year ended December 31, 2011.

Change in fair value of warrant liability.    In connection with our January 2010 registered direct offering, we issued warrants to purchase an aggregate of 1,612,322 shares of common stock which became exercisable as of the closing of the transaction. The warrants have an initial exercise price of $3.55 per share and have a five year term, and the fair value of the warrants was recorded as a long-term liability. The fair value of the warrants was estimated at $2,181,000 on the January 2010 issuance date, and $1,605,000 as of December 31, 2010, using a Black-Scholes option pricing model under various probability-weighted outcomes which take into consideration the protective, but limited, cash-settlement feature for the benefit of the warrantholder that includes a possible cash-settlement option in the event of a change of control until the later to occur of (i) two years from the date of original issuance of the warrant, or January 27, 2012, and (ii) the date upon which Genentech or Roche submits an NDA for Erivedge (vismodegib) which occurred in September 2011. The warrants will be revalued each reporting period, with the resulting gains and losses recorded as the change in fair value of warrant liability in the income statement. We estimated that the fair value of the warrants at December 31, 2010 was $1,605,000 using this same model with the following assumptions assigned to the varying outcomes: expected volatilities of 77.1% and 91.5%, risk free interest rates ranging from 1.0% to 1.6%, expected lives of three to four years and no dividends. Expected volatility in both models was based on our historical volatility commensurate with the term of the warrants. We estimated that the fair value of the warrants at December 31, 2011 was $4,361,000 using this same model with the following assumptions assigned to the varying outcomes: expected volatility of 78%, a risk free interest rate of 0.4%, expected life of three years and no dividends. We recorded a charge of $2,756,000 and a gain of $576,000 for the years ended December 31, 2011 and 2010, respectively, as a result of the increase in the fair value of the warrant liability from December 31, 2010 and issuance, primarily related to the increase in our stock price during this period.

Other Income

For the year ended December 31, 2011, interest and other income was $100,000 as compared to $627,000 for the year ended December 31, 2010, a decrease of $527,000, or 84%. The decrease relates to federal tax grants totaling $489,000 that we received in the fourth quarter of 2010 under the Patient Protection and Affordable Care Act of 2010 that we did not receive in 2011. In addition, interest income decreased $38,000 from the prior year period due to lower investment balances throughout 2011 as compared to 2010.

Net Loss Applicable to Common Stockholders

As a result of the foregoing, we incurred a net loss applicable to common stockholders of $9,859,000 for the year ended December 31, 2011, as compared to $4,435,000 for the year ended December 31, 2010.

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Years Ended December 31, 2010 and 2009

Revenues

Total revenues are summarized as follows: