FENNEC PHARMACEUTICALS INC. - Annual Report: 2007 (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, 2007

OR

For the transition period from              to             

Commission File Number: 001-32295

ADHEREX TECHNOLOGIES INC.

(Exact Name of Registrant as Specified in Its Charter)

(919) 484-8484

(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.    YES  x    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.  x

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. (Check one):

(Do not check if a smaller reporting company)

Indicated by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    YES  ¨    NO  x

The aggregate market value of the voting stock held by non-affiliates of the Registrant, computed by reference to the closing sales price of the Common Shares as reported by The American Stock Exchange on June 30, 2007, (the last business day of the Registrant’s most recently completed second fiscal quarter) was $45,226,358 based upon a total of 83,752,514 shares held as of June 30, 2007 by persons believed to be non-affiliates of the Registrant. (For purposes of this calculation, all of the Registrant’s officers, directors and 10% owners known to the Company are deemed to be affiliates of the Registrant.)

As of March 17, 2008, there were 128,226,787 shares of common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Registrant’s definitive Proxy Statement to be filed for its 2008 Annual Meeting of Stockholders currently scheduled to be held May 14, 2008 are incorporated into Part III of this report.

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ADHEREX TECHNOLOGIES INC.

2007 FORM 10-K ANNUAL REPORT

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NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains forward-looking statements that involve significant risks and uncertainties. Our actual results, performance or achievements may be materially different from any results, performance or achievements expressed or implied by such forward-looking statements. Words such as “may,” “will,” “expect,” “believe,” “anticipate,” “intend,” “could,” “estimate,” “project,” “plan,” and other similar words are one way to identify such forward-looking statements. Forward-looking statements in this Annual Report include, but are not limited to, statements with respect to (1) our anticipated commencement dates, completion dates and results of clinical trials; (2) our anticipated progress and costs of our clinical and preclinical research and development programs; (3) our corporate and development strategies; (4) our expected results of operations; (5) our anticipated levels of expenditures; (6) our ability to protect our intellectual property; (7i) the anticipated applications and efficacy of our drug candidates; (8) our ability to attract and retain key employees; (9) our efforts to pursue collaborations with the government, industry groups or other companies; (10) the nature and scope of potential markets for our drug candidates and (11) our anticipated sources and uses of cash, cash equivalents and short-term investments. All statements, other than statements of historical fact, included in this Annual Report that address activities, events or developments that we expect or anticipate will or may occur in the future are forward-looking statements. We include forward-looking statements because we believe that it is important to communicate our expectations to our investors. However, all forward-looking statements are based on management’s current expectations of future events and are subject to a number of risks and uncertainties, including those discussed below in Item 1.A., “Risk Factors.” Although we believe the expectations reflected in the forward-looking statements are based upon reasonable assumptions, we can give no assurance that our expectations will be attained, and we caution you not to place undue reliance on such statements.

Overview

We are a biopharmaceutical company focused on cancer therapeutics with preclinical and clinical product candidates. The following product candidates are in the clinical stage of development:

Our preclinical portfolio includes: (i) backup peptides and small chemical molecule successors to ADH-1; (ii) peptides and small molecules targeted to inhibiting the metastatic spread of some cancers; and (iii) peptides that combine both angiolytic and antiangiogenic properties. We have synthesized small chemical molecules and peptide antagonists and agonists for a wide array of cadherin adhesion molecules, with drug candidates available to move into future clinical development, particularly in the following areas:

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In addition to our current development efforts, we continue to pursue collaborations with other pharmaceutical companies, governmental agencies or corporate collaborators with respect to these and other cadherin molecules. Our drug discovery and development efforts are supported by more than 50 issued U.S. patents and more than 50 issued and pending patents worldwide that we either own or have exclusively licensed.

Adherex Technologies Inc. is incorporated under the Canada Business Corporations Act and has three wholly-owned subsidiaries: Oxiquant, Inc. and Adherex, Inc., both Delaware corporations, and Cadherin Biomedical Inc., a Canadian company.

Eniluracil

Eniluracil was previously under development by GSK for the treatment of cancer and is being developed by Adherex to enhance the therapeutic value and effectiveness of 5-FU, one of the world’s most widely used oncology agents. 5-FU is currently used as the first or second line therapy for colorectal, breast, gastric, head and neck, ovarian and basal cell cancer of the skin, among others. Eniluracil is expected to make 5-FU more effective by increasing its half-life, reducing its side effects and making it orally available.

Normally, 5-FU is rapidly broken down in the body by an enzyme known as dihydropyrimidine dehydrogenase, or DPD. Eniluracil irreversibly inhibits DPD, thereby substantially slowing the breakdown of 5-FU and prolonging exposure of the tumor cells to the drug.

While 5-FU is a current mainstay of contemporary oncology treatment, it has some therapeutic drawbacks:

When eniluracil is properly used in combination with 5-FU, it may resolve many of the therapeutic drawbacks of 5-FU noted above. For instance, combining eniluracil and 5-FU is expected to have the following benefits:

Thus, the use of eniluracil in combination with 5-FU has the potential to make 5-FU more effective, better tolerated and orally active.

The combination of eniluracil and 5-FU may also expand the range of cancers that currently respond to 5-FU. Some tumors, such as liver, prostate and lung cancers, have inherently high levels of DPD that result in resistance to 5-FU. Eniluracil may eliminate these high levels of DPD activity in the tumor, thereby potentially expanding the use of 5-FU to new cancer indications.

GSK’s clinical development program for the combination of 5-FU and eniluracil met with success in early development. However, three Phase III trials failed, and development was stopped. We believe new scientific data obtained by Adherex subsequent to those Phase III trials may account for the early suboptimal efficacy and provide a basis for enhancing the effectiveness of the combination. This proprietary data formed the basis of a patent application by Adherex, which claims that the combination of eniluracil and 5-FU has the potential to be more effective than 5-FU alone when used in accordance with Adherex’s proprietary methods.

Adherex’s initial development plan for eniluracil is focused on two indications: 1) liver (hepatocellular) cancer, and 2) taxane- and anthracycline-resistant breast cancer. Several other potential cancer indications are also being evaluated.

Liver cancer is one of the most common cancers in the world. In the U.S., there are approximately 19,000 new cases per year. Adherex has received orphan drug designation from the U.S. Food and Drug Administration, or FDA, for the use of eniluracil in combination with fluoropyrimidines (including 5-FU) to treat liver cancer. The rationale for targeting liver cancer is: 1) liver cancer has intrinsically high levels of DPD, making it resistant to treatment with 5-FU. Eniluracil inhibits DPD and therefore, may make liver cancer more susceptible to therapy with 5-FU, and 2) two Phase II studies conducted by GSK in liver cancer showed extended periods of stable disease and survival, even though these studies were conducted using what now appears to be a suboptimal dose and schedule.

Our second development strategy is in taxane- and anthracycline-resistant breast cancer. Capecitabine (Xeloda^®) is currently approved for this indication, yet therapy with capecitabine often results in a painful side effect known as hand-foot syndrome (reported to occur in up to 60% of patients), frequently requiring dose reduction or cessation of therapy. A breakdown product of 5-FU known as F-BAL is thought to be responsible for this side effect. Eniluracil irreversibly inhibits DPD, the enzyme responsible for the breakdown of 5-FU to metabolites such as F-BAL. In GSK’s earlier studies with eniluracil in combination with 5-FU, the incidence of hand-foot syndrome was less than 2%. Adherex may, therefore, be able to seek approval for eniluracil through either a reduced toxicity profile in comparison to capecitabine or an enhanced efficacy profile, or both.

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To optimize our proprietary method of administration for the combination of eniluracil and 5-FU, we commenced a Phase I dose escalation study in patients with solid tumors in 2007. As of February 28, 2008, we had not reached the Maximum Tolerated Dose, or MTD, for eniluracil. Upon completion of this study, we plan to commence a Phase II trial in breast cancer. In the fourth quarter of 2006, we also commenced a Phase I/II clinical trial in liver cancer in Asia. Once we obtain the MTD for eniluracil in the Phase I arm of this trial, we will immediately commence the Phase II portion of the trial and expect that it will take approximately six month to complete patient accruals in the Phase II portion of the trial. Together, these two studies are intended to define the optimal dose of eniluracil, the optimal dose ratio and schedule of eniluracil in combination with 5-FU, and the clinical response rate to our proprietary combination of these two drugs.

ADH-1

ADH-1 is a small peptide that selectively targets N-cadherin present on certain tumor cells and the established blood vessels that supply blood to the tumor. Pursuant to a general collaboration agreement, McGill granted us an exclusive worldwide license to certain intellectual property rights relating to ADH-1 and uses thereof. N-cadherin is found throughout the body and, like other cadherins, is important in cell-to-cell binding and in maintaining the structural integrity of cells. ADH-1 appears to inhibit the binding of the N-cadherin protein molecules to each other. Within tumors, the N-cadherin protein can be found on the tumor cells themselves and on the blood vessels that supply blood to the tumor. Therefore, N-cadherin is a single target where antagonizing N-cadherin binding with ADH-1 could have a dual effect; both on the tumor cells directly and on the tumor blood vessels. In our Phase I single-agent studies, radiologic changes consistent with areas of cell death (by either apoptosis or necrosis) were observed following administration of ADH-1.

In 2006, we began conducting preclinical studies of ADH-1 in combination with various chemotherapy agents. In preclinical melanoma studies, significant synergistic anti-tumor activity was observed when systemic ADH-1 was given in combination with regionally-infused melphalan (a generic chemotherapy typically used in this setting), where all of the animals on study achieved complete remission of their tumors, and the tumors remained in complete remission during the entire two-month timeframe of the studies. A similar study was conducted in a melanoma animal model that was resistant to treatment with melphalan. The combination of melphalan and ADH-1 in the melphalan-resistant models also produced striking synergistic effects, with significant tumor growth delay being observed compared to the untreated and melphalan-alone control groups.

Based on this preclinical data, we initiated a clinical program of ADH-1 in combination with various chemotherapeutic agents. In October 2006, we initiated a Phase I study intended to define the dose limiting toxicities and maximum tolerated dose of ADH-1 in combination with three separate chemotherapies: ADH-1 + docetaxel (Taxotere^®), ADH-1 + carboplatin (a generically available agent), and ADH-1 + capecitabine (Xeloda^®). We have completed patient enrollment in the docetaxel and capecitabine arms and expect to complete patient enrolment in the carboplatin arm shortly. In March 2007, we also initiated a Phase I study combining systemic ADH-1 in combination with regionally-infused melphalan for the treatment of melanoma at Duke University.

In January 2008, we announced the completion of patient enrollment in our Phase I study combining systemic ADH-1 with regionally-infused melphalan for the treatment of melanoma and commenced a Phase IIb expansion of the study. We expect to enroll up to 25 additional patients in the Phase IIb portion of the study. To gain multi-institutional experience, we have also added the M.D. Anderson Cancer Center in Houston, Texas, the Lehigh Valley Hospital in Pennsylvania and the H. Lee Moffitt Cancer Center in Tampa, Florida as participating clinical trial sites. This Phase IIb expansion trial is anticipated to complete patient accruals by approximately mid-2008.

STS

STS is currently approved by the FDA for use in humans as part of a treatment for cyanide poisoning. We have licensed from OHSU intellectual property rights for the use of STS as a chemoprotectant, and are developing STS as a protectant against the hearing loss often caused by platinum-based anti-cancer agents, in both children and adults. Preclinical and clinical studies conducted by OHSU and others have indicated that STS can effectively reduced the incidence of hearing loss caused by platinum-based anti-cancer agents. We have received Orphan Drug Designation in the United States for the use of STS in the prevention of platinum-induced ototoxicity in pediatric patients. The Company is also considering a trial with STS to study hearing loss in adult patients taking cisplatin-based chemotherapy.

Hearing loss among children receiving platinum-based chemotherapy is frequent, permanent and often severely disabling. The incidence of hearing loss in these children depends upon the dose and duration of chemotherapy, and many of these children require lifelong hearing aids. There is currently no established preventive agent for this hearing loss and only expensive, technically difficult and sub-optimal cochlear (inner ear) implants have been shown to provide some relief. In addition, adults undergoing chemotherapy for several common malignancies, including ovarian cancer, testicular cancer, and particularly head and neck cancer and brain cancer, receive intensive platinum-based therapy and may experience severe, irreversible hearing loss, particularly in the high frequencies.

Investigators at OHSU have conducted Phase I and Phase II studies which have shown STS reduces the hearing loss associated with platinum-based chemotherapy. In one study at OHSU, the need for hearing aids to correct high frequency hearing loss was reduced from about 50% to less than 5%.

In October 2007, we announced that our collaborative partner, the International Childhood Liver Tumour Strategy Group (known as SIOPEL), a multi-disciplinary group of specialists under the umbrella of the International Society of Pediatric Oncology, had launched a randomized Phase III clinical trial to investigate whether STS reduces hearing loss in children receiving cisplatin, a platinum-based chemotherapy often used in children. The study initially opened in the United Kingdom and will include SIOPEL centers in up to 33 further countries. The clinical trial is expected to enroll approximately 100 children with liver (hepatoblastoma) cancer. Patients will receive either cisplatin or cisplatin plus STS. The study, which is being coordinated through the Children’s Cancer and Leukemia Group in the United Kingdom, is intended to compare the level of hearing loss associated with cisplatin alone versus the combination of cisplatin plus STS, as well as the safety, tolerability and anti-tumor activity in both arms of the study. Under the terms of our agreement, SIOPEL will conduct and fund the clinical activity and we will provide drug and drug distribution for the study.

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On March 26, 2008, we announced the activation of a Phase III trial with STS to prevent hearing loss in children receiving cisplatin-based chemotherapy in collaboration with the Children’s Oncology Group, or COG. The goal of this Phase III study is to evaluate in a multi-centered, randomized trial whether STS is an effective and safe means of preventing hearing loss in children receiving cisplatin-based chemotherapy for newly diagnosed germ cell, liver (hepatoblastoma), brain (medulloblastoma), nerve tissue (neuroblastoma) or bone (osteosarcoma) cancers. Eligible children will be one to eighteen years of age who are to receive cisplatin according to their disease-specific regimen and, upon enrollment onto this study, will be randomized to receive STS or not. Efficacy of STS will be determined through comparison of hearing sensitivity at follow-up relative to baseline measurements using standard audiometric techniques. The trial is expected to enroll up to 120 patients over approximately three years in up to 230 COG centers in the United States, Canada, Australia and Europe. COG will fund the clinical activities for the study and we will be responsible for providing the drug and drug distribution for the study.

Preclinical Portfolio

Our product candidates are in the early stages of clinical development, so we strive to maintain a robust preclinical portfolio to hedge against unavoidable development risks and to provide possible new product candidates for the future. In considering our product candidates, note that we are subject to the risks of failure that are inherent in the development of therapeutic products based on innovative technologies as described in Item 1A, “Risk Factors.”

Our preclinical portfolio includes: (i) backup peptides and small chemical molecule successors to ADH-1; (ii) peptides and small molecules targeted to inhibiting the metastatic spread of some cancers; and (iii) peptides that combine both angiolytic and antiangiogenic properties. We have synthesized small chemical molecules and peptide antagonists and agonists for a wide array of cadherin adhesion molecules, with drug candidates available to move into future clinical development, particularly in the following areas:

In addition to our own development efforts, we intend to continue to pursue collaborations with other pharmaceutical companies, government entities or corporate collaborators with respect to our most promising agents. In 2005, we received approval from the Drug Development Group, or DDG, of the National Cancer Institute’s, or NCI, Division of Cancer Treatment and Diagnosis for a Level III collaboration for the clinical development of our lead biotechnology compound, ADH-1. As part of that collaboration, we executed a Clinical Trial Agreement, or CTA, with the NCI’s Cancer Therapy Evaluation Program and Developmental Therapeutics Program to support additional preclinical studies of ADH-1 in preparation for future NCI-sponsored clinical trials to further evaluate the anti-cancer and vascular targeting effects of ADH-1 both as a single agent and in combination with other anti-cancer agents. We also entered into a standard form screening agreement with the NCI in 2003, under which NCI continues to screen and test select Adherex compounds from our preclinical pipeline for their anti-cancer properties in various preclinical anti-cancer assays and tumor models. The NCI has no obligation to sponsor future clinical trials of ADH-1 or to continue to perform preclinical or screening work for us and may terminate the CTA or screening agreement at any time, as may we.

Intellectual Property

Our general policy is to seek patent protection in the United States, major European countries, Japan, Canada and other jurisdictions as appropriate for our compounds and methods. Our cadherin-based patent portfolio currently includes patents with respect to our unique composition of matter, broad claims with respect to modulating cell adhesion, specific claims for the use of these compounds in various diseases and pharmaceutical formulations of these compounds. We have also sought patent protection with respect to alternate “sites” of cell adhesion activity as well as related compounds, screening methods and antibodies. With respect to the intellectual property licensed from GSK, McGill and OHSU, we work closely with these institutions to continually strengthen and expand our worldwide patent protection.

Currently, we own or have licensed more than 50 issued U.S. patents and more than 50 issued and pending patents worldwide. ADH-1 is currently protected under issued composition of matter patents in the United States that we exclusively licensed from McGill that expire in 2017. Eniluracil is currently protected under issued composition of matter and method patents that we exclusively licensed from GSK that expire in 2014 and 2015 (in combination with 5-fluorouracil). STS is currently protected by method of use patents that we exclusively licensed from OHSU that expire in Europe in 2021 and are currently pending in the United States. None of the above expiry dates take into consideration additional pending patent applications for ADH-1 and eniluracil that, if issued, could provide additional patent protection nor possible patent term extensions or periods of data exclusivity that may be available upon marketing approval in the various countries worldwide. In addition, periods of marketing exclusivity for ADH-1 and STS may also be possible in the United States under orphan drug status. We obtained U.S. Orphan Drug Designation for the use of STS in the prevention of platinum-induced ototoxicity in pediatric patients in 2004 and for the use of ADH-1 in conjunction with melphalan for the treatment of Stage IIB/C, III, and IV malignant melanoma in 2008, and as a result, if approved, will have seven years of exclusivity in the United States from the approval date.

Our success is significantly dependent on our ability to obtain and maintain patent protection for our product candidates, both in the United States and abroad. The patent position of biotechnology and pharmaceutical companies, in general, is highly uncertain and involves complex legal

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and factual questions, which often results in apparent inconsistencies regarding the breadth of claims allowed and general uncertainty as to their legal interpretation and enforceability. Further, some of our principal candidates, including STS, are based on previously known compounds, and candidates or products that we develop in the future may include or be based on the same or other compounds owned or produced by other parties, some or all of which may not be subject to effective patent protection. In addition, regimens that we may develop for the administration of pharmaceuticals, such as specifications for the frequency, timing and amount of dosages, may not be patentable. Accordingly, our patent applications may not result in patents being issued and issued patents may not afford effective protection. In addition, products or processes that we develop may turn out to be covered by third party patents, in which case we may require a license under such patents if we intend to continue the development of those products or processes.

Corporate Relationships

General Collaboration Agreement with McGill University

In February 2001, we entered into a general collaboration agreement with McGill University. Pursuant to the terms of the agreement, McGill granted us a 27-year exclusive worldwide license to develop, use and market certain cell adhesion technology and compounds. In particular, McGill granted us an exclusive worldwide license to U.S. Patent 6,031,072 covering specific compounds including ADH-1 (composition of matter), U.S. Patent 6,551,994 covering alpha-catenin and beta-catenin inhibiting compounds, related international filings under the Patent Cooperation Treaty (“PCT”), continuations and certain other patents and patent applications.

In consideration, we issued 508,416 shares of our common stock to McGill. We also agreed to pay to McGill future royalties of 2% of any gross revenues from the use of the technology and compounds. In addition, we agreed to fund research at McGill over a period of 10 years totaling CAD$3.3 million. Annual funding commenced in 2001, the first year of the agreement, for a total of CAD$200,000, and increases annually by 10% through 2010, when the required annual funding reaches CAD$500,000. This research commitment can be deferred in any given year if it would exceed 5% of our cash and cash equivalents. To date, there have been no deferrals and we have paid out approximately CAD$1.5 million in research and development milestone funding to McGill pursuant to this agreement and other research-related payments. Pursuant to the terms of the agreement, we are entitled to certain intellectual property rights that result from this research.

The term of the general collaboration agreement expires on September 23, 2028, unless earlier terminated by operation of law or as provided in the agreement. The agreement is terminable by either Adherex or McGill in the event of an uncured breach by either party after 60 days prior written notice. We also have the right to terminate the agreement at any time after September 2006 upon 60 days prior written notice to McGill.

License Agreement with Oregon Health & Science University

In November 2002, we acquired an exclusive license agreement with OHSU through our acquisition of Oxiquant, which had entered into the license agreement with OHSU in September 2002. Pursuant to the license agreement, OHSU granted us an exclusive worldwide license to intellectual property directed to thiol-based compounds including STS and their use in oncology. In consideration, OHSU was issued 250,250 shares of common stock of Oxiquant that were subsequently converted upon the acquisition of Oxiquant into 382,514 shares of Adherex common stock and warrants to purchase shares of Adherex common stock that expired in 2007. In addition, we are required to make the following milestone payments: (i) $50,000 upon completion of Phase I clinical trials, (ii) $200,000 upon completion of Phase II clinical trials, (iii) $500,000 upon completion of Phase III clinical trials, and (iv) $250,000 upon the first commercial sale for any licensed product. We are also required to pay OHSU a 2.5% royalty on net sales of any licensed products and a 15% royalty on any consideration received from sublicensing of the licensed technology.

The term of the license agreement expires on the date of the last to expire claim(s) covered in the patents licensed to us, unless earlier terminated as provided in the agreement. The agreement is terminable by OHSU in the event of a material breach of the agreement by us or our sublicensees after 60 days prior written notice from OHSU. We have the right to terminate the agreement at any time upon 60 days prior written notice and payment of all fees due to OHSU under the agreement.

Development and License Agreement with GlaxoSmithKline

In July 2005, Adherex licensed eniluracil from GlaxoSmithKline, or GSK. Under the original terms of the Development and License Agreement, Adherex received an exclusive license for eniluracil for all indications, and GSK retained options to buy back the compound at various points in time during its development in return for milestone payments and sales royalties to Adherex. GSK made a concurrent equity investment of $3.0 million to assist in its further development.

In March 2007, Adherex purchased all of GSK’s remaining options to buy back eniluracil under the agreement for a $1.0 million fee. Adherex now has full control over the development of eniluracil and is required to pay GSK development and sales milestone payments and sales royalties. Specifically, if we file a New Drug Application with the FDA, we will be obligated to pay GSK development milestones of $5.0 million. Depending upon the commercial success of eniluracil, we may also be required to pay GSK up to an additional $70.0 million in development and sales milestones, plus double-digit royalties based on our annual net sales. If we pursue other indications, we may be required to pay up to an additional $15.0 million to GSK for each indication approved by the FDA.

Competition

Competition in the biotechnology and pharmaceutical industries is intense. We expect that if any of our product candidates achieve regulatory approval for sale, they will compete on the basis of drug efficacy, safety, patient convenience, reliability, ease of manufacture, price, marketing, distribution and patent protection, among other variables. Our competitors may develop technologies or drugs that are more effective, safer or affordable than any we may develop.

There are a number of different approaches to the development of therapeutics for the treatment of cancer that are currently being used and studied. These approaches include: (i) surgery to excise the cancerous tissue; (ii) radiation therapy, which attacks cancerous cells but does not easily distinguish between healthy and diseased cells; (iii) chemotherapy, which works by preventing a cancerous cell from dividing or by killing cells that

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quickly divide; (iv) immunotherapy, which stimulates the body’s immune system to respond to the disease; and (v) hormone therapy, which may slow the growth of cancer cells or even kill them.

We are aware of a number of companies engaged in the research, development and testing of new cancer therapies or means of increasing the effectiveness of existing therapies, including, among many others, Abbott Laboratories, Amgen, Antisoma, AstraZeneca, Bayer, Bristol-Myers Squibb, EntreMed, Genentech, Merck & Co., NeoPharm, Novartis, Johnson & Johnson, OSI Pharmaceuticals, Onyx, OXiGENE, Peregrine Pharmaceuticals, Pfizer, Roche, Taiho and Sanofi-Aventis. Some of these companies have products that have already received, or are in the process of receiving, regulatory approval or are in later stages of clinical development than our products. Many of them have greater financial resources than we do. Many of these companies have marketed drugs or are developing targeted cancer therapeutics which, depending upon the mechanism of action of such agents, could be viewed as competitors. However, we are not aware of any other N-cadherin targeted compounds in clinical trials. Because cancer treatment often consists of using different drug combinations, it is possible that agents that are either marketed (e.g., Taxotere^®) or investigational could be combined with ADH-1 (after achievement of applicable regulatory requirements and approvals) in an effort to improve the efficacy in comparison to the agents used alone. In other words, while a drug with a similar mechanism of action, or with anti-tumor activity in a disease where ADH-1 is also shown to be active, could be viewed as a potential competitor when both drugs are used alone, the combination could prove to be superior to the current standard of care.

We are aware of at least four companies, AstraZeneca, Aventis, OXiGENE and Roche that are clinically developing cancer angiolytics. Their product candidates are tubulin depolymerizing agents that destroy the scaffold-like structure that supports the lining cells (endothelial cells) of blood vessels, causing the endothelial cells to round and cut off blood flow through the blood vessel. They cut off a tumor’s blood supply and lead to tumor cell death. Some other angiolytic agents are known to us to be in preclinical development, including antibodies to tumor blood vessel wall components and agents linked with liposomal cytotoxic agents, but little information about these agents is publicly available at this time. These competing angiolytics work in a very different manner than ADH-1 and, to our knowledge, we are the only company approaching tumor angiolysis from the perspective of peptide-based cadherin antagonism. Tumor angiolysis is an emerging field, and our competitors’ tubulin depolymerizing agents, like our drug candidates, are still in clinical development. OXiGENE has initiated a Phase III study with its angiolytic agent in the United Kingdom. To our knowledge, no other angiolytic compounds have entered late-stage development. Accordingly, it is premature to speculate on the potential advantages and disadvantages of different angiolytic agents because the efficacy and tolerability profiles of these agents are not yet publicly available.

Anti-angiogenic compounds, which aim to prevent the growth of new tumor vessels, may compete with angiolytic compounds like ADH-1, but they may also be complementary. For instance, it may be useful to consider the use of an anti-angiogenic agent in sequential therapy with an angiolytic agent as a way to initially destroy existing tumor vessels and subsequently prevent new tumor blood vessel growth.

Programmed cell death or apoptosis has a critical role in the maintenance of healthy tissues. It has been increasingly recognized that defects in apoptotic mechanisms and pathways commonly occur to allow cancer cells to survive and flourish. In fact, the defects in the apoptotic pathways are fundamental properties of cancer biology. In recent years, the molecular underpinning of apoptosis pathways has received considerable attention and provides another opportunity for potential therapeutic intervention by inducing apoptosis in tumor cells. ADH-1 is thought to trigger apoptosis in cancer cells. Many other such apoptosis inducers are in preclinical and clinical development as oncology therapeutics candidates with companies that include Sanofi-Aventis, Abbott Laboratories, Novartis, Pfizer and Merck & Co.

There are several potential therapies that may be competitive to our eniluracil, including capecitabine (Xeloda^®) which is an oral pro-drug of 5-FU marketed by Roche that is converted to 5-FU following absorption from the gastrointestinal tract. Capecitabine is approved by the FDA and many other regulatory agencies worldwide for use in breast and colorectal cancer. UFT, marketed by Merck KGaA, is another oral 5-FU pro-drug that has not been approved by the FDA, but which is marketed in Japan and several European countries.

5-FU is normally rapidly metabolized and broken down by the enzyme DPD. Eniluracil is an irreversible inhibitor of DPD and its use with 5-FU leads to prolonged and elevated levels of 5-FU. Uracil is a competitive inhibitor of DPD. Although not FDA approved as a therapeutic agent, uracil has been used with 5-FU and tegafur, a reversible DPD inhibitor (5-chloro-2, 4-dihydrozypyidine, or CDHP) for the treatment of certain cancers. UFT is an orally active combination of uracil and tegafur that is available in some international markets through Merck KGaA.

S-1, which is marketed by Taiho in Japan and under development by Sanofi-Aventis elsewhere in the world, is an orally active combination of tegafur and oxonic acid, an inhibitor of phosphoribosyl pyrophosphate transferase, an enzyme that reduces the incorporation of 5-FU into RNA. Other reversible DPD inhibitors are in development, including a Roche molecule, Ro 09-4889, which has completed a Phase I clinical study. To our knowledge, no other irreversible DPD inhibitors are currently in development.

We are not aware of any commercially available agents that reduce the incidence of hearing loss associated with the use of platinum-based anti-cancer agents, for which purpose we are developing STS. We are aware of one company, Sound Pharmaceuticals, that is developing agents for noise, age related hearing loss and the side effects of chemotherapy. We are also aware of research relating to the use of high doses of amifostine (another thiol-based drug used to control some of the side effects of chemotherapy and radiation therapy) for the protection of hearing in connection with platinum-based chemotherapy, but such research has generally shown it to be less effective than STS for this purpose. Cochlear implants, which are small electronic devices that are surgically placed in the inner ear to assist with certain types of deafness, are utilized to offer some relief but are often suboptimal.

Many chemotherapeutic agents are currently available and numerous others are being developed. Any chemotherapeutic products that we develop may not be able to compete effectively with existing or future chemotherapeutic agents. Our competitors might obtain regulatory approval for their drug candidates sooner than we do, or their drugs may prove to be more effective than ours are. However, cancer as a disease is not currently controlled by any one anti-cancer agent, and there is typically a need for several agents at any one time and over time.

Many of our existing or potential competitors have substantially greater financial, technical and human resources than we do and may be better equipped to develop, manufacture and market products. In addition, many of these competitors have extensive experience with preclinical testing and human clinical trials and in obtaining regulatory approvals. In addition, many of the smaller companies that compete with us have formed

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collaborative relationships with large, established companies to support the research, development, clinical trials and commercialization of any products that they may develop. We may rely on third parties to commercialize the products we develop, and our success will depend in large part on the efforts and competitive merit of these collaborative partners. Academic institutions, government agencies and other public and private research organizations may also conduct research, seek patent protection and establish collaborative arrangements for research, clinical development and marketing of products similar to those we seek to develop. These companies and institutions compete with us in recruiting and retaining qualified scientific and management personnel as well as in acquiring technologies complementary to our projects. The existence of competitive products, including products or treatments of which we are not aware, or products or treatments that may be developed in the future, may adversely affect the marketability of any products that we may develop.

Government Regulation

The production and manufacture of our product candidates and our research and development activities are subject to significant regulation for safety, efficacy and quality by various governmental authorities around the world.

In Canada, these activities are subject to regulation by Health Canada’s Therapeutic Products Directorate, or TPD, and the rules and regulations promulgated under the Food and Drug Act. In the United States, drugs and biological products are subject to regulation by the FDA. The FDA requires licensing of manufacturing and contract research facilities, carefully controlled research and testing of products, governmental review and approval of results prior to marketing therapeutic products. Additionally, the FDA requires adherence to “Good Laboratory Practices” as well as “Good Clinical Practices” during clinical testing and “Good Manufacturing Practices” and adherence to labeling and supply controls. The systems of new drug approvals in Canada and the United States are substantially similar, and are generally considered to be among the most rigorous in the world.

Generally, the steps required for drug approval in Canada and the United States, specifically in cancer related therapies, include:

Preclinical Studies: Preclinical studies, also known as non-clinical studies, primarily involve evaluations of pharmacology, toxic effects, pharmacokinetics and metabolism of a drug in animals to provide evidence of the relative safety and bioavailability of the drug prior to its administration to humans in clinical studies. A typical program of preclinical studies takes 18 to 24 months to complete. The results of the preclinical studies as well as information related to the chemistry and comprehensive descriptions of proposed human clinical studies are then submitted as part of the Investigational New Drug, or IND, application to the FDA, a Clinical Trial Application to the TPD, or similar submission to other foreign regulatory bodies. This is necessary in Canada, the United States and most other countries prior to undertaking clinical studies. Additional preclinical studies are conducted during clinical development to further characterize the toxic effects of a drug prior to submitting a marketing application.

Phase I Clinical Trials: Most Phase I clinical trials take approximately one year to complete and are usually conducted on a small number of healthy human subjects to evaluate the drug’s safety, tolerability and pharmacokinetics. In some cases, such as cancer indications, Phase I clinical trials are conducted in patients rather than healthy volunteers.

Phase II Clinical Trials: Phase II clinical trials typically take one to two years to complete and are generally carried out on a relatively small number of patients (generally between 15 and 50 patients) in a specific setting of targeted disease or medical condition, in order to provide an estimate of the drug’s effectiveness in that specific setting. This phase also provides additional safety data and serves to identify possible common short-term side effects and risks in a somewhat larger group of patients. Phase II testing frequently relates to a specific disease, such as breast or lung cancer. Some contemporary methods of developing drugs, particularly molecularly targeted therapies, do not require broad testing in specific diseases, and instead permit testing in subsets of patients expressing the particular marker. In some cases, such as cancer indications, the company sponsoring the new drug may submit a marketing application to seek accelerated approval of the drug based on evidence of the drug’s effect on a “surrogate endpoint” from Phase II clinical trials. A surrogate endpoint is a laboratory finding or physical sign that may not be a direct measurement of how a patient feels, functions or survives, but is still considered likely to predict therapeutic benefit for the patient. If accelerated approval is received, the company sponsoring the new drug must continue testing to demonstrate that the drug indeed provides therapeutic benefit to the patient.

Phase III Clinical Trials: Phase III clinical trials typically take two to four years to complete and involve tests on a much larger population of patients suffering from the targeted condition or disease. These studies involve conducting controlled testing and/or uncontrolled testing in an expanded patient population (several hundred to several thousand patients) at separate test sites (multi-center trials) to establish clinical safety and effectiveness. These trials also generate information from which the overall benefit-risk relationship relating to the drug can be determined and provide a basis for drug labeling. Phase III trials are generally the most time consuming and expensive part of a clinical trial program. In some instances, governmental authorities (such as the FDA) will allow a single Phase III clinical trial to serve as a pivotal efficacy trial to support a Marketing Application.

Marketing Application: Upon completion of Phase III clinical trials, the pharmaceutical company sponsoring the new drug assembles all the chemistry, preclinical and clinical data and submits it to the TPD or the FDA as part of a New Drug Submission in Canada or a New Drug Application in the United States. The marketing application is then reviewed by the regulatory body for approval to market the product. The review process generally takes twelve to eighteen months.

Any clinical trials that we conduct may not be successfully completed, either in a satisfactory time period or at all. The typical time periods described above may vary substantially and may be materially longer. In addition, the FDA and its counterparts in other countries have considerable discretion to discontinue trials if they become aware of any significant safety issues or convincing evidence that a therapy is not effective for the indication being tested. The FDA and its counterparts in other countries may not (i) allow clinical trials to proceed at any time after receiving an IND, (ii) allow further clinical development phases after authorizing a previous phase, or (iii) approve marketing of a drug after the completion of clinical trials.

While European, U.S. and Canadian regulatory systems require that medical products be safe, effective, and manufactured according to high quality standards, the drug approval process in Europe differs from that in the United States and Canada and may require us to perform additional

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preclinical or clinical testing regardless of whether FDA or TPD approval has been obtained. The amount of time required to obtain necessary approvals may be longer or shorter than that required for FDA or TPD approval. European Union Regulations and Directives generally classify health care products either as medicinal products, medical devices or in vitro diagnostics. For medicinal products, marketing approval may be sought using either the centralized procedure of the European Agency for the Evaluation of Medicinal Products, or EMEA, or the decentralized, mutual recognition process. The centralized procedure, which is mandatory for some biotechnology derived products, results in an approval recommendation from the EMEA to all member states, while the European Union mutual recognition process involves country by country approval.

An investment in our common stock involves a significant risk of loss. You should carefully read this entire report and should give particular attention to the following risk factors. You should recognize that other significant risks may arise in the future, which we cannot foresee at this time. Also, the risks that we now foresee might affect us to a greater or different degree than currently expected. There are a number of important factors that could cause our actual results to differ materially from those expressed or implied by any of our forward-looking statements in this report. These factors include, without limitation, the risk factors listed below and other factors presented throughout this report and any other documents filed by us with the SEC.

Risks Related to Our Business

We will need to raise substantial additional funds in the future to continue our operations.

We believe that our current cash and cash equivalents will be sufficient to satisfy our anticipated capital requirements through June 30, 2009. Our projections of our capital requirements through June 30, 2009 and beyond, however are subject to substantial uncertainty. Our current and future working capital requirements may change depending upon numerous factors, including: results of our research and development activities; progress or lack of progress in our preclinical studies or clinical trials; our drug substance requirements to support clinical programs; our ability to enter into collaborations that provide us with funding, up-front payments, milestone or other payments; changes in the focus, direction, or costs of our research and development programs; the costs involved in preparing, filing, prosecuting, maintaining, defending and enforcing our patent claims; competitive and technological advances; the potential need to develop, acquire or license new technologies and products; the establishment of marketing and sales capabilities; our business development activities; new regulatory requirements implemented by regulatory authorities; the timing and outcome of any regulatory review process; and our commercialization activities, if any. Any such change could mean additional capital may be required earlier than June 2009 or more capital thereafter may be required than we had anticipated. To finance our operations beyond June 2009, or earlier if necessary, we will need to raise substantial additional funds through either the sale of additional equity, the issuance of debt, the establishment of collaborations that provide us with funding, the out-license or sale of certain aspects of our intellectual property portfolio, or from other sources. We might not be able to raise the necessary capital or such funding may not be available on favorable terms or at all.

We have a history of significant losses and have had no revenues to date through the sale of our products. If we do not generate significant revenues, we will not achieve profitability.

To date, we have been engaged primarily in research and development activities. We have had no revenues to date through the sale of our products, and we do not expect to have significant revenues until we are able to either sell our product candidates after obtaining applicable regulatory approvals or we establish collaborations that provide us with licensing fees, milestone payments, royalties, up-front payments or other revenue. We have incurred significant operating losses every year since our inception on September 3, 1996. We have experienced net losses of approximately $13.4 million for the fiscal year ended December 31, 2007, $16.4 million for the fiscal year ended December 31, 2006 and $13.9 million for the fiscal year ended December 31, 2005. As of December 31, 2007 we had an accumulated deficit of approximately $84.4 million. We anticipate incurring substantial additional losses over the next several years due to the need to expend substantial amounts on our continuing clinical trials, anticipated research and development activities, and general and administrative expenses, among other factors. We have not commercially introduced any product and our product candidates are in varying stages of development and testing. Our ability to attain profitability will depend upon our ability to develop products that are safe, effective and commercially viable, to obtain regulatory approval for the manufacture and sale of our product candidates and to license or otherwise market our product candidates successfully. Any revenues generated from such products, assuming they are successfully developed, marketed and sold, may not be realized for a number of years. We may never achieve or sustain profitability on an ongoing basis.

Our product candidates are still in development. Due to the long, expensive and unpredictable drug development process, we might not ever successfully develop and commercialize any of our product candidates.

In order to achieve profitable operations, we, alone or in collaboration with others, must successfully develop, manufacture, introduce and market our product candidates. The time necessary to achieve market success for any individual product is long and uncertain. Our product candidates and research programs are in various stages of clinical development and require significant, time-consuming and costly research, testing and regulatory clearances. In developing our product candidates, we are subject to risks of failure that are inherent in the development of therapeutic products based on innovative technologies. For example, our product candidates might not be effective, as eniluracil was shown to be in earlier clinical trials conducted by GSK, or may be overly toxic, or otherwise might fail to receive the necessary regulatory clearances. The results of preclinical and initial clinical trials are not necessarily predictive of future results. Our product candidates might not be economical to manufacture or market or might not achieve market acceptance. In addition, third parties might hold proprietary rights that preclude us from marketing our product candidates or others might market superior or equivalent products.

We must conduct human clinical trials to assess our product candidates. If these trials are delayed or are unsuccessful, our development costs will significantly increase and our business prospects may suffer.

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Before obtaining regulatory approvals for the commercial sale of our product candidates, we must demonstrate, through preclinical studies with animals and clinical trials with humans, that our product candidates are safe and effective for use in each target indication. To date, we have performed only limited clinical trials, and we have only done so with some of our product candidates. Much of our testing has been conducted on animals or on human cells in the laboratory, and the benefits of treatment seen in animals may not ultimately be obtained in human clinical trials. As a result, we will need to perform significant additional research and development and extensive preclinical and clinical testing prior to any application for commercial use. We may suffer significant setbacks in clinical trials, and the trials may demonstrate our product candidates to be unsafe or ineffective. We may also encounter problems in our clinical trials that will cause us to delay, suspend or terminate those clinical trials, which would increase our development costs and harm our financial results and commercial prospects. Identifying and qualifying patients to participate in clinical trials of our potential products is critically important to our success. The timing of our clinical trials depends on the speed at which we can recruit patients to participate in testing our product candidates. We have experienced delays in some of our clinical trials, including a significant delay in the activation of our STS Phase III study with COG, and we may experience significant delays in the future. If patients are unwilling to participate in our trials because of competitive clinical trials for similar patient populations, perceived risk or any other reason, the timeline for recruiting patients, conducting trials and obtaining regulatory approval of potential products will be delayed. Other factors that may result in significant delays include obtaining regulatory or ethics review board approvals for proposed trials, reaching agreement on acceptable terms with prospective clinical trial sites, and obtaining sufficient quantities of drug for use in the clinical trials. Such delays could result in termination of the clinical trials altogether.

Regulatory approval of our product candidates is time-consuming, expensive and uncertain, and could result in unexpectedly high expenses and delay our ability to sell our products.

Development, manufacture and marketing of our products are subject to extensive regulation by governmental authorities in the United States and other countries. This regulation could require us to incur significant unexpected expenses or delay or limit our ability to sell our product candidates, including specifically eniluracil, ADH-1 and STS, our product candidates that are farthest along in development and the regulatory approval process.

Our clinical studies might be delayed or halted, or additional studies might be required, for various reasons, including:

If regulatory approval of any product is granted, it will be limited to those indications for which the product has been shown to be safe and effective, as demonstrated to the FDA’s satisfaction through clinical studies. Furthermore, approval might entail ongoing requirements for post-marketing studies. Even if regulatory approval is obtained, labeling and promotional activities are subject to continual scrutiny by the FDA and state regulatory agencies and, in some circumstances, the Federal Trade Commission. FDA enforcement policy prohibits the marketing of approved products for unapproved, or off-label, uses. These regulations and the FDA’s interpretation of them might impair our ability to effectively market our products.

We and our third-party manufacturers are also required to comply with the applicable FDA current Good Manufacturing Practices, or GMP, regulations, which include requirements relating to quality control and quality assurance, as well as the corresponding maintenance of records and documentation. Further, manufacturing facilities must be approved by the FDA before they can be used to manufacture our products, and they are subject to additional FDA inspection. If we fail to comply with any of the FDA’s continuing regulations, we could be subject to reputational harm and sanctions, including:

In addition, identification of side effects after a drug is on the market or the occurrence of manufacturing problems could cause subsequent withdrawal of approval, reformulation of the drug, additional testing or changes in labeling of the product.

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If we do not maintain current or enter into new collaborations with other companies, we might not successfully develop our product candidates or generate sufficient revenues to expand our business.

We currently rely on scientific and research collaboration arrangements with academic institutions and other collaborators, including our Development and License Agreement for eniluracil with GSK, a general collaboration agreement with McGill University for ADH-1 and other related compounds, and an exclusive worldwide license from OHSU for STS.

The agreements with McGill and OHSU are terminable by either party in the event of an uncured breach by the other party. We may also terminate our agreement with McGill and OHSU at any time upon prior written notice of specified durations to the licensor. Termination of any of our collaborative arrangements could materially adversely affect our business. In addition, our collaborators might not perform as agreed in the future.

In addition to the collaborative arrangements above, we have received approval from the DDG of the U.S. National Cancer Institute’s Division of Cancer Treatment and Diagnosis for a Level III collaboration for the clinical development of our lead biotechnology compound, ADH-1. The NCI has no obligation to sponsor future clinical trials of ADH-1 or to continue to perform any preclinical work for us and may terminate the collaboration at any time, as may we. The success of our business strategy will be dependent on our ability to maintain current and enter into new collaborations with other industry participants that advance the development and clinical testing of, regulatory approval for and commercialization of our product candidates, as well as collaborations that provide us with funding, such as licensing fees, milestone payments, royalties, up-front payments or otherwise. We may not be successful in maintaining current collaborations or establishing any future collaborations and any collaborations we have or may establish may not lead to the successful development of our product candidates.

Since we conduct a significant portion of our early stage research and development through collaborations, our success may depend significantly on the performance of such collaborators, as well as any future collaborators. Collaborators might not commit sufficient resources to the research and development or commercialization of our product candidates. Economic or technological advantages of products being developed by others, or other factors could lead our collaborators to pursue other product candidates or technologies in preference to those being developed in collaboration with us. The commercial potential of, development stage of and projected resources required to develop our drug candidates will affect our ability to maintain current collaborations or establish new collaborators. There is a risk of dispute with respect to ownership of technology developed under any collaboration. Our management of any collaboration will require significant time and effort as well as an effective allocation of resources. We may not be able to simultaneously manage a large number of collaborations.

We do not presently have the financial or human resources to complete Phase III trials for our lead product candidates.

We do not presently have the financial or human resources internally to complete Phase III trials for any of our lead product candidates. We are currently developing STS in a Phase III trial in collaboration with SIOPEL and COG. SIOPEL and COG may not conduct or complete the clinical trials with STS as currently planned. Such collaborators might not commit sufficient resources to the development of our product candidates, which may lead to significant delays. We have already experienced significant delays in getting the COG trial launched. We may not be able to independently develop or conduct such trials ourselves. We intend to seek a licensing or funding partner for the further development of one or all of our products. If a partner for one or all of these technologies is not found, we may not be able to further advance these products. If a partner is found, the financial terms that they propose may not be acceptable to us.

As we expand the size of our organization, we may experience difficulties in effectively managing our growth, which could adversely impact our business.

Our planned future growth will strain our management, human, operational, financial and other resources. As of December 31, 2007, we had 19 full-time employees. We also use contractors as needed, primarily within the clinical development function with approximately five (5) full time equivalents at December 31, 2007. In order to manage our future growth effectively, we will have to implement and improve operational, financial, manufacturing and management information systems and to expand, train, manage and motivate our employees. To the extent that we are unable to manage our growth effectively, we may not be able to successfully accomplish our business objectives.

We may expand our business through new acquisitions that could disrupt our business, harm our financial condition and dilute current stockholders’ ownership interests in the Company.

Our business strategy includes expanding our products and capabilities, and we may seek acquisitions to do so. Acquisitions involve numerous risks, including:

We cannot assure you that any acquisition will result in short-term or long-term benefits to us. We may incorrectly judge the value or worth of an acquired company or business. In addition, our future success would depend in part on our ability to assimilate acquired companies and their personnel effectively. We might not be able to make the combination of our business with that of acquired businesses or companies work or be successful. Furthermore, the development or expansion of our business or any acquired business or companies may require a substantial capital

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investment by us. We may not have the necessary funds or they might not be available to us on acceptable terms or at all. We may also seek to raise the necessary funds by selling shares of our stock, which could dilute current stockholder’s ownership interest in our Company.

If we lose our key personnel or are unable to attract and retain personnel, we may be unable to effectively manage our business and successfully develop our product candidates.

Our success depends upon certain key personnel, in particular Dr. William P. Peters, our Chief Executive Officer and Chairman of the Board, the loss of whose services might significantly delay or prevent the achievement of our scientific or business objectives. Although we have an employment agreement with Dr. Peters through March 2010, and with each of our other key personnel, we cannot be certain that any individual will continue in such capacity for any particular period of time. The loss of any key personnel, or the inability to hire and retain qualified employees, could negatively affect our ability to manage our business. We do not currently carry key person life insurance.

If our licenses to proprietary technology owned by others are terminated or expire, we may suffer increased development costs and delays, and we may not be able to successfully develop our product candidates.

The development of our drug candidates and the manufacture and sale of any products that we develop will involve the use of processes, products and information, some of the rights to which are owned by others. A number of our product candidates are licensed under agreements with GSK, McGill and OHSU. Although we have obtained licenses or rights with regard to the use of certain processes, products and information, the licenses or rights could be terminated or expire during critical periods and we may not be able to obtain, on favorable terms or at all, licenses or other rights that may be required. Some of these licenses provide for limited periods of exclusivity that may be extended only with the consent of the licensor, which may not be granted.

If we are unable to adequately protect our patents and licenses related to our product candidates, or we infringe upon the intellectual property rights of others, we may not be able to successfully develop and commercialize our product candidates.

The value of our technology will depend in part upon our ability, and that of our collaborators, to obtain patent protection or licenses to patents, maintain trade secret protection and operate without infringing on the rights of third parties. Although we have successfully pursued patent applications in the past, it is possible that:

It is not possible for us to be certain that we are the original and first creator of inventions encompassed by our pending patent applications or that we were the first to file patent applications for any such inventions. Further, any of our patents, once issued, may be declared by a court to be invalid or unenforceable.

ADH-1 is currently protected under issued composition of matter patents in the United States that we exclusively licensed from McGill that expire in 2017. Eniluracil is currently protected under issued composition of matter and method patents that we exclusively licensed from GSK that expire in 2014 and 2015 (in combination with 5-fluorouracil). STS is currently protected by method of use patents that we exclusively licensed from OHSU that expire in Europe in 2021 and are currently pending in the United States. None of the above expiry dates take into consideration additional pending patent applications for ADH-1 and eniluracil that, if issued, could provide additional patent protection nor possible patent term extensions or periods of data exclusivity that may be available upon marketing approval in the various countries worldwide. In addition, periods of marketing exclusivity for ADH-1 and STS may also be possible in the United States under orphan drug status. We obtained U.S. Orphan Drug Designation for the use of STS in the prevention of platinum-induced ototoxicity in pediatric patients in 2004 and for the use of ADH-1 in conjunction with melphalan for the treatment of Stage IIB/C, III, and IV malignant melanoma in 2008, and as a result, if approved, will have seven years of exclusivity in the United States from the approval date.

We may be required to obtain licenses under patents or other proprietary rights of third parties but the extent to which we may wish or need to do so is unknown. Any such licenses may not be available on terms acceptable to us or at all. If such licenses are obtained, it is likely they would be royalty bearing, which would reduce our income. If licenses cannot be obtained on an economical basis, we could suffer delays in market introduction of planned products or their introduction could be prevented, in some cases after the expenditure of substantial funds. If we do not obtain such licenses, we would have to design around patents of third parties, potentially causing increased costs and delays in product development and introduction or precluding us from developing, manufacturing or selling our planned products, or our ability to develop, manufacture or sell products requiring such licenses could be foreclosed.

Litigation may also be necessary to enforce or defend patents issued or licensed to us or our collaborators or to determine the scope and validity of a third party’s proprietary rights. We could incur substantial costs if litigation is required to defend ourselves in patent suits brought by third parties, if we participate in patent suits brought against or initiated by our collaborators, or if we initiate such suits. We might not prevail in any such action. An adverse outcome in litigation or an interference to determine priority or other proceeding in a court or patent office could subject us to significant liabilities, require disputed rights to be licensed from other parties or require us or our collaborators to cease using certain technology or products. Any of these events would likely have a material adverse effect on our business, financial condition and results of operations.

Much of our technological know-how that is not patentable may constitute trade secrets. Our confidentiality agreements might not provide for meaningful protection of our trade secrets, know-how or other proprietary information in the event of any unauthorized use or disclosure of information. In addition, others may independently develop or obtain similar technology and may be able to market competing products and obtain

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regulatory approval through a showing of equivalency to our product that has obtained regulatory approvals, without being required to undertake the same lengthy and expensive clinical studies that we would have already completed.

The vulnerability to off-label use or sale of our product candidates that are covered only by “method of use” patents may cause downward pricing pressure on these product candidates if they are ever commercialized and may make it more difficult for us to enter into collaboration or partnering arrangements for the development of these product candidates.

Some of our product candidates, including STS, are currently only covered by “method of use” patents, which cover the use of certain compounds to treat specific conditions, and not by “composition of matter” patents, which would cover the chemical composition of the compound. Method of use patents provide less protection than composition of matter patents because of the possibility of off-label competition if other companies develop or market the compound for other uses. If another company markets a drug that we expect to market under the protection of a method of use patent, physicians may prescribe the other company’s drug for use in the indication for which we obtain approval and have a patent, even if the other company’s drug is not approved for such an indication. Off-label use and sales could limit our sales and exert pricing pressure on any products we develop covered only by method of use patents. Also, it may be more difficult to find a collaborator to license or support the development of our product candidates that are only covered by method of use patents.

If our third party manufacturers breach or terminate their agreements with us, or if we are unable to secure arrangements with third party manufacturers on acceptable terms as needed in the future, we may suffer significant delays and additional costs.

We have no experience manufacturing products and do not currently have the resources to manufacture any products that we may develop. We currently have agreements with contract manufacturers for clinical supplies of ADH-1, STS, eniluracil and 5-FU, including drug substance providers and drug product suppliers, but they might not perform as agreed in the future or may terminate our agreement with them before the end of the required term. Significant additional time and expense would be required to effect a transition to a new contract manufacturer.

We plan to continue to rely on contract manufacturers for the foreseeable future to produce quantities of products and substances necessary for research and development, preclinical trials, human clinical trials and product commercialization, and to perform their obligations in a timely manner and in accordance with applicable government regulations. If we develop any products with commercial potential, we will need to develop the facilities to independently manufacture such products or secure arrangements with third parties to manufacture them. We may not be able to independently develop manufacturing capabilities or obtain favorable terms for the manufacture of our products. While we intend to contract for the commercial manufacture of our product candidates, we may not be able to identify and qualify contractors or obtain favorable contracting terms. We or our contract manufacturers may also fail to meet required manufacturing standards, which could result in delays or failures in product delivery, increased costs, injury or death to patients, product recalls or withdrawals and other problems that could significantly hurt our business. We intend to maintain a second source for back-up commercial manufacturing, wherever feasible. However, if a replacement to our future internal or contract manufacturers were required, the ability to establish second-sourcing or find a replacement manufacturer may be difficult due to the lead times generally required to manufacture drugs and the need for FDA compliance inspections and approvals of any replacement manufacturer, all of which factors could result in production delays and additional commercialization costs. Such lead times would vary based on the situation, but might be twelve months or longer.

We lack the resources necessary to effectively market our product candidates, and we may need to rely on third parties over whom we have little or no control and who may not perform as expected.

We do not have the necessary resources to market our product candidates. If we develop any products with commercial potential, we will either have to develop a marketing capability, including a sales force, which is difficult and expensive to implement successfully, or attempt to enter into a collaboration, merger, joint venture, license or other arrangement with third parties to provide a substantial portion of the financial and other resources needed to market such products. We may not be able to do so on acceptable terms, if at all. If we rely extensively on third parties to market our products, the commercial success of such products may be largely outside of our control.

We conduct our business internationally and are subject to laws and regulations of several countries which may affect our ability to access regulatory agencies and may affect the enforceability and value of our licenses.

We have conducted clinical trials in the United States, Canada, Europe and the Pacific Rim and intend to, or may, conduct future clinical trials in these and other jurisdictions. There can be no assurance that any sovereign government will not establish laws or regulations that will be deleterious to our interests. There is no assurance that we, as a Canadian corporation, will continue to have access to the regulatory agencies in any jurisdiction where we might want to conduct clinical trials or obtain regulatory approval, and we might not be able to enforce our license or patent rights in foreign jurisdictions. Foreign exchange controls may have a material adverse effect on our business and financial condition, since such controls may limit our ability to flow funds into or out of a particular country to meet obligations under licenses, clinical trial agreements or other collaborations.

Risks Related to Our Industry

If we are unable to obtain applicable U.S. and/or foreign regulatory approvals, we will be unable to develop and commercialize our drug candidates.

The preclinical studies and clinical trials of our product candidates, as well as the manufacturing, labeling, sale and distribution, export or import, marketing, advertising and promotion of our product candidates are subject to various regulatory frameworks in the United States, Canada and other countries. Any products that we develop must receive all relevant regulatory approvals and clearances before any marketing, sale or distribution. The regulatory process, which includes extensive preclinical studies and clinical testing to establish product safety and efficacy, can take many years and cost substantial amounts of money. As a result of the length of time, many challenges and costs associated with the drug development process, the historical rate of failures for drug candidates is extremely high. For example, prior development of our compound eniluracil by GSK was not successful. Varying interpretations of the data obtained from studies and tests could delay, limit or prevent regulatory

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approval or clearance. Changes in regulatory policy could also cause delays or affect regulatory approval. Any regulatory delays may increase our development costs and negatively impact our competitiveness and prospects. It is possible that we may not be able to obtain regulatory approval of any of our drug candidates or approvals may take longer and cost more to obtain than expected.

Regulatory approvals, if granted, may entail limitations on the uses for which any products we develop may be marketed, limiting the potential sales for any such products. The granting of product approvals can be withdrawn at any time, and manufacturers of approved products are subject to regular reviews, including for compliance with GMP. Failure to comply with any applicable regulatory requirement, which may change from time to time, can result in warning letters, fines, sanctions, penalties, recalling or seizing products, suspension of production, or even criminal prosecution.

Future sales of our product candidates may suffer if they fail to achieve market acceptance.

Even if our product candidates are successfully developed and achieve appropriate regulatory approval, they may not enjoy commercial acceptance or success. Product candidates may compete with a number of new and traditional drugs and therapies developed by major pharmaceutical and biotechnology companies. Market acceptance is dependent on product candidates demonstrating clinical efficacy and safety, as well as demonstrating advantages over alternative treatment methods. In addition, market acceptance is influenced by government reimbursement policies and the ability of third parties to pay for such products. Physicians, patients, the medical community or patients may not accept or utilize any products we may develop.

We face a strong competitive environment. Other companies may develop or commercialize more effective or cheaper products, which may reduce or eliminate the demand for our product candidates.

The biotechnology and pharmaceutical industry, and in particular the field of cancer therapeutics where we focus, is very competitive. Many companies and research organizations are engaged in the research, development and testing of new cancer therapies or means of increasing the effectiveness of existing therapies, including, among many others, Abbott Laboratories, Amgen, Antisoma, Adventrix, AstraZeneca, Bayer, Bristol-Myers Squibb, EntreMed, Genentech, Johnson & Johnson, Merck & Co., NeoPharm, Novartis, Onyx, OSI Pharmaceuticals, OXiGENE, Peregrine Pharmaceuticals, Pfizer, Roche, Taiho and Sanofi-Aventis. Many of these companies have marketed drugs or are developing targeted cancer therapeutics which, depending upon the mechanism of action of such agents, could thus be competitors.

Many of our existing or potential competitors have substantially greater financial, technical and human resources than we do and may be better equipped to develop, manufacture and market products. In addition, many of these competitors have extensive experience with preclinical testing and human clinical trials and in obtaining regulatory approvals. Also, some of the smaller companies that compete with us have formed collaborative relationships with large, established companies to support the research, development, clinical trials and commercialization of any products that they may develop. Academic institutions, government agencies and other public and private research organizations may also conduct research, seek patent protection and establish collaborative arrangements for research, clinical development and marketing of products similar to those we seek to develop. These companies and institutions compete with us in recruiting and retaining qualified scientific and management personnel as well as in acquiring technologies complementary to our projects.

We are likely to face competition in the areas of product efficacy and safety, ease of use and adaptability, as well as pricing, product acceptance, regulatory approvals and intellectual property. Competitors could develop more effective, safer and more affordable products than we do, and they may obtain patent protection or product commercialization before we do or even render our product candidates obsolete. The existence of competitive products, including products or treatments of which we are not aware, or products or treatments that may be developed in the future, may adversely affect the marketability of any products that we develop.

We may face product liability claims that could require us to defend costly lawsuits or incur substantial liabilities that could adversely impact our financial condition, receipt of regulatory approvals for our product candidates and our results of operation.

The use of our product candidates in clinical trials and for commercial applications, if any, may expose us to liability claims in the event that such product candidates cause injury or death or result in other adverse effects. These claims could be made by health care institutions, contract laboratories, subjects participating in our clinical studies, patients or others using our product candidates. In addition to liability claims, certain serious adverse events could require interruption, delay and/or discontinuation of a clinical trial and potentially prevent further development of the product candidate. We carry clinical trial insurance with a policy limit of $5.0 million, but the coverage may not be sufficient to protect us from legal expenses and liabilities we might incur. Litigation is very expensive, even if we are successful. In addition, our existing coverage may not be adequate if we further develop products, and future coverage may not be available in sufficient amounts or at reasonable cost. Adverse liability claims may also harm our ability to obtain or maintain regulatory approvals.

We use hazardous material and chemicals in our research and development, and our failure to comply with laws related to hazardous materials could materially harm us.

Our research and development processes involve the controlled use of hazardous materials, such as flammable organic solvents, corrosive acids and corrosive bases. Accordingly, we are subject to federal, state, local and foreign laws and regulations governing the use, manufacture, storage, handling and disposal of such materials and certain waste products. While we believe that our safety procedures for handling and disposing of such materials will comply with the standards prescribed by applicable federal, state, local or foreign regulations, the risk of accidental contamination or injury from these materials cannot be completely eliminated. In the event of such an accident, we could be held liable for any damages that result and any such liability could exceed our resources and may not be covered by our general liability insurance. We currently do not carry insurance specifically for hazardous materials claims. We may be required to incur significant costs to comply with environmental laws and regulations, which may change from time to time.

Efforts to reduce product pricing and health care reimbursement and changes to government policies could negatively affect the commercialization of our product candidates.

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If any of our product candidates achieve regulatory approval, we may be materially adversely affected by the continuing efforts of governmental and third-party payors to contain or reduce health care costs. For example, if we succeed in bringing one or more products to market, such products may not be considered cost-effective and the availability of consumer reimbursement may not exist or be sufficient to allow the sale of such products on a competitive basis. The constraints on pricing and availability of competitive products may further limit our pricing and reimbursement policies as well as adversely impact market acceptance and commercialization for the products.

In some foreign markets, the pricing or profitability of healthcare products is subject to government control. In recent years, federal, state, provincial and local officials and legislators have proposed or are proposing a variety of price-based reforms to the healthcare systems in the United States and Canada. Some proposals include measures that would limit or eliminate payments from third-party payors to the consumer for certain medical procedures and treatments or allow government control of pharmaceutical pricing. The adoption of any such proposals or reforms could adversely affect the commercial viability of our product candidates.

Any significant changes in the healthcare system in the United States, Canada or abroad would likely have a substantial impact on the manner in which we conduct business and could have a material adverse effect on our ability to raise capital and the viability of product commercialization.

New accounting or regulatory pronouncements may impact our future financial position and results of operations.

There may be new accounting or regulatory pronouncements or rulings, which could have an impact on our future financial position and results of operations. Changing laws, regulations and standards relating to corporate governance and public disclosures can create uncertainty and such uncertainty may lead to increased expenses and exposure to liabilities.

Risks Related to Owning Our Common Shares

We are a passive foreign investment company under U.S. tax law, which has adverse tax consequences for our U.S. shareholders.

As further described in Item 5. “Market for the Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities” – “Material United States Federal and Canadian Income Tax Consequences” in our Annual Report on Form 10-K, we have determined that we are currently a Passive Foreign Investment Company, or PFIC, under U.S. tax law and likely will continue to be a PFIC at least until we develop a source of significant operating revenues. As a result, there may be adverse tax consequences to U.S. holders of our common shares. A U.S. holder whose holding period for our shares includes a period during which we are classified as a PFIC generally may be required to treat certain excess distributions with respect to our shares and gains realized on the disposition of our shares as ordinary income earned ratably over the holder’s holding period and may be subject to a special tax and interest charge on amounts treated as earned in the periods in which we are a PFIC. In addition, the holder’s shares may not receive a “stepped-up” basis upon a transfer at death. These PFIC tax rules may not apply if a U.S. holder makes an election for the first taxable year of the holder’s holding period to be taxed currently on the holder’s pro rata share of our ordinary earnings and net capital gain for any year we are a PFIC. Alternatively, a U.S. holder may avoid the special tax and interest charge on excess distributions and gains by making an election to mark the shares to market annually during any period in which we are a PFIC and our shares are treated as marketable shares. If a mark-to-market election is made, amounts included in or deducted from income pursuant to the election and actual gains and losses realized upon disposition generally may be treated as ordinary gains or losses. Whether or not an applicable election is made, if we are classified as a PFIC for the taxable year in which a dividend is paid, or for the preceding taxable year, a dividend paid to a non-corporate U.S. holder may not qualify for the reduced long-term capital gains rates. These tax issues could make our stock less attractive to U.S. investors and therefore negatively affect our stock price and the ability to sell our shares.

The market price of our Common Shares is highly volatile and could cause the value of your investment to significantly decline.

Historically, the market price of our common shares has been highly volatile and the market for our common shares has from time to time experienced significant price and volume fluctuations, some of which are unrelated to our operating performance. From November 12, 2004 to March 17, 2008, the trading price of our stock fluctuated from a high closing price of CAD$2.09 per share to a low closing price of CAD$0.23 per share on the TSX, and from a high closing price of $1.71 per share to a low closing price of $0.20 per share on the AMEX. Historically, our common shares have had a low trading volume, and may continue to have a low trading volume in the future. This low volume may contribute to the volatility of the market price of our common shares. It is likely that the market price of our common shares will continue to fluctuate significantly in the future.

The market price of our stock may be significantly affected by many factors, including without limitation:

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There are a large number of our common shares underlying outstanding warrants and options, and reserved for issuance under our stock option plan, that may be sold in the market, which could depress the market price of our stock and result in substantial dilution to the holders of our common shares.

Sale or issuance of a substantial number of our common shares in the future could cause the market price of our common stock to decline. It may also impair our ability to obtain additional financing. As of December 31, 2007, we had outstanding warrants to purchase approximately 7.6 million of our common shares at an exercise price of CAD$2.15 per share, and outstanding warrants to purchase approximately 48.2 million of our common shares at exercise prices ranging from $0.33 to $1.75. In addition, as of December 31, 2007, there were approximately 15.6 million common shares issuable upon the exercise of stock options granted by us of which approximately 2.9 million were denominated in Canadian dollars and had a weighted average exercise price of CAD$2.18 per common share and approximately 12.7 million denominated in U.S. dollars and had a weighted average exercise price of $0.58 per common share. In addition, on February 27, 2008, we issued 3.2 million stock options with an exercise price of $0.38. We may also issue further warrants as part of any future financings as well as the additional 1.8 million common shares currently remaining available for issuance under our stock option plan.

We are no longer a foreign private issuer and may incur additional expenses associated with compliance with the U.S. securities laws applicable to U.S. domestic issuers.

We must now comply with the provisions of U.S. securities laws applicable to U.S. domestic issuers including, without limitation, the U.S. proxy solicitation rules, Regulation FD and the Section 16 short swing profit rules. As a result, we must now report on the forms required of U.S. companies, such as Forms 10-K, 10-Q and 8-K, rather than the forms we have filed with the SEC in the past as a foreign private issuer, such as Forms 20-F and 6-K. Compliance with these additional securities laws may result in increased expenses. In addition, we will now be subject to additional restrictions on offers and sales of securities outside of the United States, including in Canada. To the extent that we were to offer or sell our securities outside of the United States in the future, we will have to comply with the generally more restrictive Regulation S requirements that apply to U.S. companies.

We have not paid any dividends since incorporation and do not anticipate declaring any dividends in the foreseeable future. As a result, you will not be able to recoup your investment through the payment of dividends on your Common Shares and the lack of a dividend payable on our Common Shares might depress the value of your investment.

We will use all available funds to finance the development of our product candidates and operation of our business. Our directors will determine if and when dividends should be declared and paid in the future based on our financial position at the relevant time, but since we have no present plans to pay dividends, you should not expect receipt of dividends either for your cash needs or to enhance the value of your common shares.

There is no public market for our outstanding warrants.

We have not and do not intend to list any of our outstanding warrants on any securities exchange or to arrange for any quotation system to quote them. We cannot assure you that there will be a liquid trading market for our warrants or that a trading market for our warrants will develop.

Our existing principal stockholders hold a substantial number of our Common Shares and may be able to exercise influence in matters requiring approval of stockholders.

As of December 31, 2007, our current 5% stockholders beneficially own approximately 60% of our Common Shares. In particular, Southpoint Capital Advisors LP owns or exercises control over 41.5 million Common Shares, representing approximately 32% of the issued and outstanding Common Shares and 42% beneficially owned (assuming full exercise of the 20.8 million warrants issued to Southpoint Capital but no other outstanding warrants or options). In addition, Mr. Robert Butts, Co-Founder and Portfolio Manager of Southpoint Capital Advisors LP, serves as a member of our Board of Directors. Southpoint Capital, our other 5% stockholders, as well as other insiders, acting alone or together, might be able to influence the outcomes of matters that require the approval of our stockholders, including but not limited to the election and removal of directors, an acquisition or merger with another company, certain equity transactions, a sale of substantially all of our assets, or amendments to our incorporating documents. These stockholders might make decisions that are adverse to your interests. The concentration of ownership could have the effect of delaying, preventing or deterring a change of control of our company, which could adversely affect the market price of our Common Shares or deprive our other stockholders of an opportunity to receive a premium for their Common Shares as part of a sale of our company.

None.

We lease two facilities, one of which we sublease to another tenant. The facility we occupy has approximately 18,272 square feet of laboratory and office space in Research Triangle Park, North Carolina and the current monthly lease payments are approximately $30,000 and the lease expires in August 2012. The subleased space consists of approximately 7,636 square feet of laboratory and office space and the current monthly payments are approximately $10,000 and the lease expires in March 2010 and is sublet through March 31, 2008. The sublease agreement is on the same terms as our original lease.

None.

None.

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Executive Officers of the Registrant

The following table sets forth information concerning our executive officers as of March 17, 2008:

William P. Peters, MD, PhD, MBA. Dr. Peters has been the Chief Executive Officer of Adherex since March 2003, the Chairman of our Board since February 2004, and a member of the Board since November 2002. From March 2003 to February 2004, Dr. Peters served as the Vice Chairman of the Board. Dr. Peters has served on the faculty at Harvard University, Duke University and Wayne State University. He originated the solid tumor high-dose chemotherapy and bone marrow transplant program at the Dana-Farber Cancer Institute, and was Director of Bone Marrow Transplantation and Professor of Medicine at Duke University from 1984 to 1995 and was an Associate Director of the Cancer Center. He then served as President, Director and CEO of the Karmanos Cancer Institute from 1995 to 2001. Simultaneously, he served as Associate Dean for Cancer at Wayne State University and Senior Vice President for Cancer Services at the Detroit Medical Center. In 2001, he organized the Institute for Strategic Analysis and Innovation at the Detroit Medical Center of which he served as President. Dr. Peters has three Bachelor degrees (Biochemistry, Biophysics and Philosophy) from Pennsylvania State University, received his MPhil, MD and PhD degrees from the Columbia University College of Physicians & Surgeons in New York and trained clinically at Harvard University Medical School’s Brigham and Women’s Hospital and Dana-Farber Cancer Institute. He is board certified in internal medicine and medical oncology. He earned his MBA at the Duke University Fuqua School of Business.

Robin J. Norris, MD. Dr. Norris has been the Chief Operating Officer of Adherex since January 2002, President of Adherex since June 2002 and a member of the Board since November 2002. Prior to joining Adherex, Dr. Norris was Chief Operating Officer and Chairman of the Scientific Advisors Committee of PowderJect plc from March 1998 to December 2001 and Chief Operating Officer of Noven Inc. from March 1995 to March 1998. Dr. Norris received his medical education and degree in the United Kingdom with postgraduate qualifications in obstetrics, general medicine and pharmaceutical medicine. Following eight years of clinical practice, Dr. Norris has spent over 25 years in the pharmaceutical industry, predominantly based in the United States, but with global drug development responsibilities. During his career, Dr. Norris has been responsible for the successful development of a wide range of pharmaceutical products and devices, moving and transitioning them from fundamental “bench-level” research and development through the regulatory process and into the global marketplace.

James A. Klein, Jr., CPA. Mr. Klein joined Adherex as Chief Financial Officer in April 2004. From 1999 to April 2004, Mr. Klein founded and served as Chief Executive Officer and Chairman of DataScout Software Inc., a company that develops and commercializes software for the pharmaceutical industry. From 1995 to 1999, Mr. Klein served as Chief Financial Officer and Treasurer of Triangle Pharmaceuticals Inc., a publicly traded pharmaceutical company. Prior to that, Mr. Klein was the International Research and Development Financial Controller for Burroughs Wellcome Co., an international pharmaceutical group. Mr. Klein is a Certified Public Accountant.

D. Scott Murray, BScPharm, LLB, MBA. Mr. Murray has been General Counsel and Corporate Secretary of Adherex since February 2003, a Vice President of the Company since September 2003 and Senior Vice President, Corporate Development since February 2007. Prior to joining Adherex, Mr. Murray was an Associate at Osler, Hoskin & Harcourt LLP in Toronto specializing in private and public corporate finance, mergers and acquisitions as well as securities compliance and pharmaceutical regulatory matters. At Osler, Hoskin & Harcourt LLP, Mr. Murray worked with a number of international pharmaceutical corporations, some of the largest securities dealers in North America, various early-stage biotechnology clients and also spent a secondment in the legal department of General Motors of Canada. Prior to joining Osler, Hoskin & Harcourt LLP, Mr. Murray practiced as a pharmacist for over seven years, including several retail pharmacy management positions. Mr. Murray holds a Bachelor of Science in Pharmacy degree from Dalhousie University and LLB and MBA degrees from the University of Ottawa.

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Part II

Our common stock has been traded on the American Stock Exchange, or AMEX, under the trading symbol “ADH” since November 12, 2004 and on the Toronto Stock Exchange, or TSX, under the trading symbol “AHX” since June 5, 2001. The following table sets forth the quarterly high and low market closing prices, and average daily trading volume on the AMEX and the TSX, for the two most recent full financial years:

On March 17, 2008, the last reported sale price on the AMEX was $0.35 per share. As of March 17, 2008, the last reported sale on the TSX was CAD$0.30 per share.

Record Holders

As of March 17, 2008, there were approximately 88 shareholders of record of our common stock, one of which was Cede & Co., a nominee for Depository Trust Company, or DTC, and one of which was The Canadian Depository for Securities Limited, or CDS. All of our common shares held by brokerage firms, banks and other financial institutions in the U.S. or Canada as nominees for beneficial owners are considered to be held of record by Cede & Co. in respect of brokerage firms, banks and other financial institutions located in Canada. Cede & Co. and CDS are each considered to be one shareholder of record.

Relative Stock Performance

The following line graph compares the percentage change, from June 30, 2003 to December 31, 2007, in cumulative total shareholder return for $100 (CAD$ for TSX and US$ for AMEX) invested in our common stock with cumulative total return of the AMEX Composite, the AMEX Biotechnology Index and the S&P/TSX Composite Total Return Index. Note the line graph reflects our change in year end from June 30^th to December 31^st in June 2004. The line graph also reflects the November 12, 2004 commencement of trading on the AMEX stock exchange.

Dividend Policy

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We have never declared or paid cash dividends on our common stock. We currently expect to retain future earnings, if any, for use in the operation and expansion of business and do not anticipate paying any cash dividends in the foreseeable future.

Material United States Federal and Canadian Income Tax Consequences

This section summarizes the material U.S. federal and Canadian federal income tax consequences of the ownership and disposition of the common stock. Nothing contained herein shall be construed as tax advice; you must rely only on the advice of your own tax advisor. We make no assurances as to the applicability of any tax laws with respect to any individual investment. In this section, we have calculated whether it meets certain thresholds related to its status under various U.S. tax rules. Any such calculation is dependent on many facts, not all of which may be known to us and any of which might change, which could change the results of any calculation.

This summary relating to the common stock applies to the beneficial owners who are individuals, corporations, trusts and estates which:

Persons who satisfy the above conditions are referred to as “U.S. Shareholders.”

The tax consequences of an investment in common stock by persons who are not U.S. Shareholders may differ materially from the tax consequences discussed in this section. The Income Tax Act contains rules relating to securities held by some financial institutions. This Annual Report does not discuss these rules, and holders that are financial institutions should consult their own tax advisors. This discussion is based upon the following, all as currently in effect:

All of the foregoing is subject to change either prospectively or retroactively. This summary does not take into account estate or gift tax laws, the tax laws of the various provinces or territories of Canada or the tax laws of the various state and local jurisdictions of the United States or foreign jurisdictions.

This discussion summarizes the material U.S. federal and Canadian federal income tax considerations of the ownership and disposition of common stock. This discussion does not address all possible tax consequences relating to an investment in common stock. No account has been taken of your particular circumstances and this summary does not address consequences peculiar to you if you are subject to special provisions of U.S. or Canadian income tax law (including, without limitation, dealers in securities or foreign currency, tax-exempt entities, banks, insurance companies or other financial institutions, persons that hold common stock as part of a “straddle,” “hedge” or “conversion transaction,” and U.S. Shareholders that have a “functional currency” other than the U.S. dollar or that own common stock through a partnership or other pass through entity). Therefore, you should consult your own tax advisor regarding the tax consequences of purchasing and owning common stock.

Material U.S. Federal Income Tax Considerations

Subject to the discussion below regarding Foreign Personal Holding Company Rules, Passive Foreign Investment Company Rules and Controlled Foreign Corporation Rules, this section summarizes U.S. federal income tax consequences of ownership and disposition of the common stock.

U.S. Shareholders are generally required to include in income dividend distributions, if any, paid by a company to the extent of a company’s current or accumulated earnings and profits attributable to the distribution as computed based on U.S. income tax principles. The amount of any cash distribution paid in Canadian dollars will be equal to the U.S. dollar value of the Canadian dollars on the date of distribution based on the exchange rate on such date, regardless of whether the payment is in fact converted to U.S. dollars and without reduction for Canadian withholding tax. For a discussion of Canadian withholding taxes applicable to dividends paid by the Company, see “Material Canadian Federal Income Tax

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Considerations.” You will generally be entitled to a foreign tax credit or deduction in an amount equal to the Canadian tax withheld. To the extent distributions paid by a company on the common stock exceed the company’s current or accumulated earnings and profits, they will be treated first as a return of capital up to your adjusted tax basis in the shares and then as capital gain from the sale or exchange of the shares.

On May 28, 2003, the Jobs and Growth Tax Relief Reconciliation Act of 2003, or the 2003 Act, was signed into law. In general, the 2003 Act reduces the maximum rate of U.S. federal income tax on dividends paid to non-corporate U.S. holders to 15% for tax years from 2003 to 2008. In order to qualify for the reduced tax rates on dividends, a non-corporate shareholder must satisfy certain holding period requirements and must not be under an obligation (whether pursuant to a short sale or otherwise) to make related payments with respect to positions in substantially similar or related property. In some circumstances, this holding period may be increased. Additionally, the new tax rates do not apply to dividends, which a non-corporate shareholder elects to treat as investment income for purposes of Section 163(d)(4) of the Code.

Dividends received from a “qualified foreign corporation” are eligible for the reduced dividends tax rates under the 2003 Act. In general, a Canadian corporation entitled to all the benefits of the Tax Treaty will be treated as a qualified foreign corporation. In addition, a foreign corporation will be treated as a qualified foreign corporation with respect to any dividend paid by that corporation if the stock with respect to which the dividend is paid is readily tradable on an established securities market in the United States. Regardless of the above rules, however, a foreign corporation will not be treated as a qualified foreign corporation if, for the taxable year of the corporation in which the dividend was paid, or the preceding taxable year, the corporation is classified for U.S. tax purposes as a foreign personal holding company, or FPHC, or a passive foreign investment company, or PFIC. Accordingly, any dividends paid by us in a year that we are a FPHC or a PFIC or in the next taxable year would not qualify for the reduced tax rates on dividends paid to non-corporate U.S. holders under the 2003 Act. As discussed below under “Foreign Personal Holding Company Rules” and “Passive Foreign Investment Company Rules,” we have determined that we are a PFIC for U.S. federal income tax purposes and likely will continue to be a PFIC at least until we develop a source of significant operating revenues.

Dividends paid by the Company generally will constitute foreign source dividend income and “passive income” for purposes of the foreign tax credit, which could reduce the amount of foreign tax credits available to you. The Code applies various limitations on the amount of foreign tax credits that may be available to a U.S. tax payer.

Because of the complexity of those limitations, you should consult your own tax advisor with respect to the availability of foreign tax credits.

Dividends paid by the Company on the common stock generally will not be eligible for the “dividend received” deduction.

If you sell the common stock, you generally will recognize gain or loss in an amount equal to the difference between the amount realized on the sale and your adjusted tax basis in the shares. Any such gain or loss will be long-term or short-term capital gain or loss, depending on whether the shares have been held by you for more than one year, and will generally be U.S. source gain or loss.

Dividends paid by the Company on the common stock generally will be subject to U.S. information reporting, and a backup withholding tax may apply unless you furnish the paying agent or middleman with a duly completed and signed Form W-9. You will be allowed a refund or a credit equal to any amount withheld under the U.S. backup withholding tax rules against your U.S. federal income tax liability, provided you furnish the required information to the Internal Revenue Service.

Foreign Personal Holding Company Rules

Special U.S. tax rules apply to a shareholder of a foreign personal holding company or FPHC. Furthermore, as discussed above, dividends from a FPHC do not qualify for the reduced tax rates on dividends paid to non-corporate U.S. holders under the 2003 Act. The Company would be classified as a FPHC in any taxable year if both of the following tests are satisfied:

We believe that we are not a FPHC. However, we cannot assure you that we will not be classified as a FPHC in the future.

Personal Holding Company Rules

We will not be classified as a personal holding company, or a PHC, for U.S. federal income tax purposes unless at any time during the last half of the Company’s taxable year, five or fewer individuals (without regard to their citizenship or residency) own or are deemed to own (pursuant to certain attribution rules) more than 50% of our stock by value, and at least 60% of our ordinary gross income for the taxable year is “personal holding company income” (generally passive income such as dividends and interest). If we are classified as a PHC, the corporation may be liable for the U.S. PHC tax on the Company’s U.S. source undistributed PHC income. The Company should not meet the PHC tests, and even if the Company were to become a PHC, it does not expect to have material undistributed PHC income. However, we cannot assure you that we will not become a PHC because of uncertainties regarding the application of the constructive ownership rules and the possibility of changes in our shareholder base and income or other circumstances that could change the application of the PHC rules. In addition, if we should become a PHC, we cannot assure you that the amount of its PHC income will be immaterial.

Passive Foreign Investment Company Rules

The passive foreign investment company or PFIC provisions of the Code can have significant tax effects on U.S. Shareholders. We will be classified as a PFIC for any taxable year, if, after the application of certain “look through” rules, either:

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Based upon our review of our financial data for the current and prior fiscal years, we have determined that we are currently a PFIC and likely will continue to be a PFIC at least until we develop a source of significant operating revenues.

Our classification as a PFIC for any period during a U.S. Shareholder’s holding period for our shares, absent the holder validly making one of the elections described below, would generally require the U.S. Shareholder to treat all “excess distributions” received during such holding period with respect to those shares as if those amounts were ordinary income earned ratably over such holding period. Excess distributions for this purpose would include all gain realized on the disposition of the shares as well as certain distributions made by us. Amounts treated under this analysis as earned in the year of the disposition or in any year before the first year in which we are a PFIC would be included in the holder’s ordinary income for the year of the disposition. Additionally, amounts treated as earned in a year of distribution would be included in the holder’s ordinary income for the year of the distribution. All remaining amounts would be subject to tax at the highest ordinary income tax rate that would have been applicable in the year in which such amounts were treated as earned, and interest would be charged on the tax payable with respect to such amounts. In addition, if we are classified as a PFIC, shares acquired from a decedent generally would not receive a “stepped-up” basis but would, instead, have a tax basis equal to the lower of the decedent’s basis or the fair market value of those shares or ADSs on the date of the decedent’s death.

The special PFIC tax rules described above will not apply to a U.S. Shareholder if the holder makes a QEF election to have us treated as a qualified electing fund for the first taxable year of the holder’s holding period in which we are a PFIC and we provide certain information to the U.S. Shareholder. A U.S. Shareholder that makes a QEF election with respect to us will be currently taxable on its pro rata share of our ordinary earnings and net capital gain during any years we are a PFIC (at ordinary income and capital gains rates, respectively), regardless of whether or not distributions were received. An electing U.S. Shareholder’s basis in the shares would be increased by the amounts included in income, and subsequent distributions by us of previously included earnings and profits generally would not be treated as a taxable dividend and would result in a corresponding reduction in basis. A U.S. Shareholder making such a timely election will not be taxed on our undistributed earnings and profits for any year that we are not a PFIC. Upon request by a U.S. shareholder, we will provide the information necessary for such holder to make the QEF election.

Alternatively, subject to specific limitations, U.S. Shareholders who actually or constructively own marketable shares in a PFIC may make an election under Section 1296 of the Code to mark those shares to market annually, rather than being subject to the above-described rules. Amounts included in or deducted from income under this mark-to-market election and actual gains and losses realized upon disposition, subject to specific limitations, will be treated as ordinary gains or losses. For this purpose, we believe that our shares will be treated as “marketable securities” within the meaning of Section 1296(e)(1) of the Code.

As discussed above, dividends from a PFIC do not qualify for the reduced tax rates on dividends paid to non-corporate U.S. Shareholders under the 2003 Act.

You should consult your tax advisor with respect to how the PFIC rules affect your tax situation.

Controlled Foreign Corporation Rules

If more than 50% of the voting power or total value of all classes of our shares are owned, directly or indirectly, by U.S. shareholders, each of which owns 10% or more of the total combined voting power of all classes of our shares, we could be treated as a controlled foreign corporation, or CFC under Subpart F of the Code. This classification would require such 10% or greater shareholders to include in income their pro rata shares of our “Subpart F Income,” as defined in the Code. In addition, under Section 1248 of the Code, gain from the sale or exchange of shares by a U.S. Shareholder who is or was a 10% or greater shareholder while we were a CFC at any time during the five year period ending with the sale or exchange will be ordinary dividend income to the extent our earnings and profits attributable to the shares sold or exchanged and not previously taxed under Subpart F.

We believe that we are not a CFC. However, we cannot assure you that we will not become a CFC in the future.

Material Canadian Federal Income Tax Considerations

This section summarizes the material anticipated Canadian federal income tax considerations relevant to the ownership and disposition of the common stock.

Under the Income Tax Act, assuming you are a U.S. Shareholder, and provided the common stock is listed on a prescribed stock exchange, which includes the Toronto Stock Exchange and the American Stock Exchange, you will generally not be subject to Canadian tax on a capital gain realized on an actual or deemed disposition of the common stock unless you alone or together with persons with whom you did not deal at arm’s length owned or had rights to acquire 25% or more of our issued shares of any class at any time during the sixty (60) month period before the actual or deemed disposition.

Dividends paid, credited or deemed to have been paid or credited on the common stock to U.S. Shareholders will be subject to a Canadian withholding tax under the Income Tax Act at a rate of 25% of the gross amount of the dividends. Under the Canada-United States Income Tax Convention (1980), or Convention, the rate of withholding tax on dividends generally applicable to U.S. Shareholders who beneficially own the dividends is reduced to 15%. In the case of U.S. Shareholders that are corporations that beneficially own at least 10% of a company’s voting shares, the rate of withholding tax on dividends generally is reduced to 5%. United States limited liability companies, or LLCs, are not currently entitled to rely on the terms of the Convention, and therefore do not benefit from these reduced rates. Under the terms of a protocol to the Convention signed in September 2007, reduced rates under the Convention will apply to members of look-through entities, such as LLCs and partnerships, who would be

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entitled to rely on the Convention if they held the common stock directly. Members of such entities will be regarded as holding their proportionate share of the common stock held by the entity for the purposes of the Convention. The protocol has not yet been ratified. The new provisions will come into effect with respect to withholding taxes at the beginning of the second month after ratification.”

Canada does not currently impose any federal estate taxes or succession duties. However, if you die, there is a deemed disposition of the common stock held at that time for proceeds of disposition generally equal to the fair market value of the common stock immediately before your death. Capital gains realized on the deemed disposition, if any, will have the income tax consequences described above.

The selected statement of operations data and balance sheet data with respect to the years ended December 31, 2007, 2006 and 2005 and the six months ended December 31, 2004 and the years ended June 30, 2004 and 2003 as set forth below are derived from our consolidated financial statements as prepared in all material respects with generally accepted accounting principles in the United States and prepared in U.S. dollars. The selected financial data set forth below should be read in conjunction with our “Management’s Discussion and Analysis of Financial Condition and Results of Operations” contained in Item 7 below and our consolidated financial statements and the notes thereto appended to this Annual Report filed on Form 10-K. These historical results are not necessarily indicative of our future results.

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CAUTIONARY STATEMENT

The discussion below contains forward-looking statements regarding our financial condition and our results of operations that are based upon our annual consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles within the United States (“U.S. GAAP”) and applicable U.S. Securities and Exchange Commission (“SEC”) regulations for financial information. The preparation of these financial statements also conform in all material respects with generally accepted accounting principles in Canada (“Canadian GAAP”) except as described in Note 15 in our annual consolidated financial statements contained in this Annual Report on Form 10-K for the year ended December 31, 2007. The preparation of these financial statements requires our management to make estimates and judgments that affect the reported amounts of assets, liabilities, income and expenses, and related disclosure of contingent assets and liabilities. We evaluate our estimates on an ongoing basis. Our estimates are based on historical experience and on various other assumptions that we believe to be reasonable.

Overview

We are a biopharmaceutical company focused on cancer therapeutics with preclinical and clinical product candidates. Our clinical product portfolio includes:

Our preclinical portfolio includes: (1) novel peptides and small chemical molecule successors to ADH-1; (2) peptides and small molecules targeting the cadherin-mediated metastatic spread of some cancers; and (3) peptides that combine both angiolytic and anti-angiogenic properties. We have synthesized small chemical molecules and peptide antagonists and agonists for a wide array of cadherin adhesion molecules, with drug candidates available to move into future clinical development, particularly in the following areas:

In addition to our current development efforts, we continue to pursue collaborations with other pharmaceutical companies, governmental agencies, academic or corporate collaborators with respect to these and other cadherin agonist and antagonist molecules. Our drug discovery and

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development efforts are supported by more than 50 issued U.S. patents and more than 50 issued and pending patents worldwide that we either own or have licensed Exclusively.

We have not received any revenues to date through the sale of our products and do not expect to have significant revenues until we are either able to sell our product candidates after obtaining applicable regulatory approvals or we establish collaborations that provide us with licensing fees, milestone payments, royalties, up-front payments or other revenue. As of December 31, 2007, our deficit accumulated during development stage was approximately $84.4 million.

Our operating expenses will depend on many factors, including the progress of our drug development efforts and the potential commercialization of our product candidates. Our research and development expenses, which include expenses associated with our clinical trials, drug manufacturing to support clinical programs, salaries for research and development personnel, stock-based compensation, consulting fees, sponsored research costs, toxicology studies, license fees, milestone payments, and other fees and costs related to the development of product candidates and will depend on the results of clinical trials, availability of financial resources and directions from regulatory agencies which are difficult to predict . Our general and administration expenses include expenses associated with the compensation of employees, stock-based compensation, professional fees, insurance and other administrative matters associated with our facilities in the Research Triangle Park, North Carolina in support of our drug development programs.

Results of Operations

Fiscal 2007 versus Fiscal 2006

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Fiscal 2006 versus Fiscal 2005

Quarterly Information

The following table presents selected consolidated financial data for each of the last eight quarters through December 31, 2007, as prepared under U.S. GAAP (dollars in thousands, except per share information):

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Liquidity and Capital Resources

We have financed our operations since inception on September 3, 1996 through the sale of equity and debt securities and have raised gross proceeds totaling approximately $86.0 million through December 31, 2007. We have incurred net losses and negative cash flow from operations each year, and we had an accumulated deficit of approximately $84.4 million as of December 31, 2007. We have not generated any revenues to date through the sale of products. We do not expect to have significant revenues or income, other than interest income, until we are able to sell our product candidates after obtaining applicable regulatory approvals or we establish collaborations that provide us with licensing fees, royalties, milestone payments or up-front payments.

On February 21, 2007, we completed the sale of equity securities for gross proceeds of $25.0 million. We issued 75.8 million units at a price of $0.33 per unit providing net proceeds of $23.2 million after deducting broker fees and other offering expenses. Each unit sold consisted of one common share and one-half of a common share purchase warrant. This financing included an aggregate of 75.8 million shares of common stock, 37.9 million investor warrants and 6.6 million broker warrants to acquire additional shares of our common stock. Each whole investor warrant entitles the holder to acquire one additional share of our common stock at an exercise price of $0.40 per share for a period of three years. Each whole broker warrant entitles the holder to acquire one unit (the same as the units sold to investors) at an exercise price of $0.33 per unit for a period of two years. During fiscal 2007, we issued 2.1 million shares of common stock pursuant to the exercise of warrants resulting in additional proceeds of approximately $0.7 million.

The net cash flow used in operating activities for the fiscal years 2007 and 2006 were relatively consistent with an average monthly cash burn of $1.1 million for each year. During fiscal 2007, we paid GSK a license fee of $1.0 million to purchase all of GSK’s remaining buy-back options for eniluracil under our development and license agreement with GSK. In addition, we had increased cash payments to vendors during the first half of fiscal 2007 from our improved liquidity as a result of our $25.0 million offering completed in February 2007.

At December 31, 2007, our working capital increased by approximately $13.0 million primarily due to the February 2007 financing. This increase was partially offset by our payments to fund R&D activities and general corporate operations.

We believe that our current cash and cash equivalents of $16.2 million will be sufficient to satisfy our anticipated capital requirements through June 30, 2009. In February 2008, we revised our clinical development strategy and implemented a plan which has allowed us to extend our existing financial resources by delaying certain clinical trial and drug manufacturing commitments. The revisions primarily relate to planned combination studies with ADH-1 and future planned orders for the manufacturing of ADH-1. We do not anticipate these revisions to have a significant impact on our overall development plan. Our projections of further capital requirements are subject to substantial uncertainty. Our working capital requirements may fluctuate in future periods depending upon numerous factors, including: results of our research and development activities; progress or lack of progress in our preclinical studies or clinical trials; unfavorable toxicology in our clinical programs, our drug substance requirements to support clinical programs; our ability to enter into collaborations that provide us with funding, up-front payments, milestone or other payments; our ability to obtain additional financial resources, change in the focus, direction, or costs of our research and development programs; the costs involved in preparing, filing, prosecuting, maintaining, defending and enforcing our patent claims; competitive and technological advances; the potential need to develop, acquire or license new technologies and products; establishment of marketing and sales capabilities; our business development activities; new regulatory requirements implemented by regulatory authorities; the timing and outcome of any regulatory review process; and commercialization activities, if any.

To finance our operations beyond June 30, 2009, we will need to raise substantial additional funds through either the sale of additional equity, the issuance of debt, the establishment of collaborations that provide us with funding, the out-license or sale of certain aspects of our intellectual property portfolio, or from other sources. There can be no assurance that we will be able to raise the necessary capital or that such funding will be available on favorable terms or at all.

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Financial Instruments

At December 31, 2007, we held cash and cash equivalents of $16.2 million, which consisted primarily of highly liquid money market funds.

Our investment policy is to manage investments to achieve, in the order of importance, the financial objectives of preservation of principal, liquidity and return on investment. Investments may be made in U.S. or Canadian obligations and bank securities, commercial paper of U.S. or Canadian industrial companies, utilities, financial institutions and consumer loan companies, and securities of foreign banks provided the obligations are guaranteed or carry ratings appropriate to the policy. Securities must have a minimum Dun & Bradstreet rating of A for bonds or R1 low for commercial paper. The policy also provides for investment limits on concentrations of securities by issuer and maximum-weighted average time to maturity of twelve months. This policy applies to all of our financial resources.

The policy risks are primarily the opportunity cost of the conservative nature of the allowable investments. As our main purpose is research and development, we have chosen to avoid investments of a trade or speculative nature.

We classify investments with original maturities at the date of purchase greater than three months which mature at or less than twelve months as current. We carry investments at the fair value with unrealized gains and losses included in accumulated other comprehensive income.

Off-Balance Sheet Arrangements

Since our inception, we have not had any material off-balance sheet arrangements.

Contractual Obligations and Commitments

Since our inception, inflation has not had a material effect on our operations. We had no material commitments for capital expenses as of December 31, 2007.

The following table represents our contractual obligations and commitments at December 31, 2007 (in thousands of U.S. dollars):

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Research and Development

Our research and development efforts have been focused on the development of cancer therapeutics and our cadherin technology platform and currently include ADH-1, eniluracil, STS and various cadherin-based preclinical programs.

We have established relationships with contract research organizations, universities and other institutions, which we utilize to perform many of the day-to-day activities associated with our drug development. Where possible, we have sought to include leading scientific investigators and advisors to enhance our internal capabilities. Research and development issues are reviewed internally by our executive management and supporting scientific staff. Major development issues are presented to the members of our Scientific and Clinical Advisory Board for discussion and review.

Research and development expenses totaled $10.9 million and $14.0 million for the fiscal years ended December 31, 2007 and 2006, respectively.

ADH-1 is a small peptide molecule that selectively targets N-cadherin, a protein present on certain tumor cells and the established blood vessels that supply tumors. Based on encouraging data from our preclinical studies, we initiated a clinical program with ADH-1 in combination with various chemotherapeutic agents. In October 2006, we initiated a Phase I study intended to define the dose limiting toxicities and maximum tolerated dose of ADH-1 in combination with three separate chemotherapies: ADH-1 + docetaxel (Taxotere^®), ADH-1 + carboplatin (a generically available agent), and ADH-1 + capecitabine (Xeloda^®). In March 2007, we initiated a second Phase I study combining systemic ADH-1 in combination with regional melphalan for the treatment of melanoma at Duke University.

Eniluracil, which we licensed from GSK in July 2005, is a DPD inhibitor that was previously under development by GSK for the treatment of cancer. Eniluracil is being developed to enhance the therapeutic value and effectiveness of 5-FU, one of the world’s most widely-used oncology agents. The ongoing Phase I clinical trials of eniluracil in combination with 5-FU are intended to determine the maximum tolerated dose, or MTD, of 5-FU in combination with eniluracil. An MTD has not yet been determined but we expect the U.S. Phase I trial to complete patient enrollment in the first half of 2008. Subject to adequate resources, we plan to commence a randomized, Phase II clinical trial in breast cancer once the MTD has been determined. The ongoing Asian Phase I/II clinical trial of eniluracil in combination with 5-FU in liver (hepatocellular) cancer has been amended to permit a more rapid dose escalation based upon the results of the ongoing U.S. Phase I trial.

STS is a chemoprotectant that has been shown in Phase I and Phase II clinical studies conducted by investigators at OHSU to reduce the loss of hearing in patients, both adults and children, treated with platinum-based chemotherapy agents. In 2006, we entered into an agreement with SIOPEL, a multi-disciplinary group of specialists under the umbrella of the International Society of Pediatric Oncology, for the conduct of a randomized trial of STS. Under the terms of our agreement, SIOPEL will conduct and fund the clinical activity and we will provide the drug and drug distribution for the study. On October 30, 2007, we announced that SIOPEL had launched the Phase III trial and opened the study for patient enrollment in the United Kingdom. The study is expected to enroll approximately 100 evaluable children with liver (hepatoblastoma) cancer at participating SIOPEL centers in up to 33 countries. Patients will be randomized to receive either cisplatin alone, a platinum-based drug associated with frequent hearing loss, or cisplatin plus STS. The study, which will be coordinated through the Children’s Cancer and Leukaemia Group in the United Kingdom, will compare the level of hearing loss associated with cisplatin alone versus the combination of cisplatin plus STS, as well as the safety, tolerability and anti-tumor activity in both arms of the study. On March 26, 2008, we announced the activation of a Phase III trial with STS to prevent hearing loss in children receiving cisplatin-based chemotherapy in collaboration with the Children’s Oncology Group, or COG. The goal of this Phase III study is to evaluate in a multi-centered, randomized trial whether STS is an effective and safe means of preventing hearing loss in children receiving cisplatin-based chemotherapy for newly diagnosed germ cell, liver (hepatoblastoma), brain (medulloblastoma), nerve tissue (neuroblastoma) or bone (osteosarcoma) cancers. Eligible children will be one to eighteen years of age who are to receive cisplatin according to their disease-specific regimen and, upon enrollment onto this study, will be randomized to receive STS or not. Efficacy of STS will be determined through comparison of hearing sensitivity at follow-up relative to baseline measurements using standard audiometric techniques. The trial is expected to enroll up to 120 patients over approximately three years in up to 230 COG centers in the United States, Canada, Australia and Europe. COG will fund the clinical activities for the study and we will be responsible for providing the drug and drug distribution for the study.

Our product candidates are in various stages of development and still require significant, time-consuming and costly research and development, testing and regulatory clearances. In developing our product candidates, we are subject to risks of failure that are inherent in the development of products based on innovative technologies. For example, it is possible that any or all of these products will be ineffective or toxic, or will otherwise fail to receive the necessary regulatory clearances. There is a risk that our product candidates will be uneconomical to manufacture or market or will not achieve market acceptance. There is also a risk that third parties may hold proprietary rights that preclude us from marketing our product candidates or that others will market a superior or equivalent product. As a result of these factors, we are unable to accurately estimate the nature, timing and future costs necessary to complete the development of these product candidates. In addition, we are unable to reasonably estimate the period when material net cash inflows could commence from the sale, licensing or commercialization of such product candidates, if ever.

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The following table provides our research and development expenses for each program for the years ending December 31, 2007, 2006 and 2005, and cumulatively from inception of the Company on September 3, 1996 to December 31, 2007:

Critical Accounting Policies and Estimates

Effective January 1, 2007, we changed our primary basis of accounting to U.S. GAAP. We made the change to U.S. GAAP to comply with U.S. securities law as a result of our loss of foreign private issuer status with the Securities and Exchange Commission.

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as at the date of the financial statements and the reported amounts of revenue and expense during the reporting period. These estimates are based on assumptions and judgments that may be affected by commercial, economic and other factors. Actual results could differ from these estimates.

An accounting policy is considered to be critical if it requires an accounting estimate to be made based on assumptions about matters that are highly uncertain at the time the estimate is made, and if different estimates reasonably could have been used, or changes in the accounting estimates that are reasonably likely to occur periodically, could materially impact the financial statements. The following description of critical accounting policies, judgments and estimates should be read in conjunction with our December 31, 2007 consolidated financial statements.

Stock-based Compensation

Effective January 1, 2006, we adopted the fair value recognition of Statement of Financial Accounting Standards, or SFAS, No. 123 (revised 2004), “Share-Based Payment”, or SFAS 123(R), using the modified prospective transition method and therefore has not restated results for prior periods. We use the Black-Scholes option-pricing model and recognize compensation expense on a straight-line basis over the vesting periods of our option awards. The estimation of stock awards that will ultimately vest requires judgment, and to the extent actual results or updated estimates differ from our current estimates, such amounts will be recorded as a cumulative adjustment in the period estimates are revised. Significant management judgment is required in determining estimates of future stock price volatility, forfeitures and expected life used in the valuation of the options. We consider many factors when estimating expected forfeitures, including types of awards and historical experience. We estimate volatility based on peer group companies with similar operations and our own historical volatility. Actual results, and future changes in estimates, may differ substantially from our current estimates. For stock options granted to non-employees, we have recognized compensation expense in accordance with the requirements of SFAS No. 123 “Accounting for Stock-based Compensation,” or SFAS 123. SFAS 123 requires that companies recognize compensation expense based on the estimated fair value of options granted to non-employees over their vesting period, which is generally the period during which services are rendered by such non-employees.

Common stock and warrants

Common stock is recorded as the net proceeds received on issuance after deducting all share issue costs and the value of investor warrants. Warrants are recorded at fair value and are deducted from the proceeds of common stock and recorded on the consolidated statements of shareholders’ equity as additional paid-in capital.

At December 31, 2007 and 2006, we had warrants to purchase common stock that were denominated in both U.S. and Canadian dollars, which results in our having warrants outstanding that are denominated outside its U.S. dollar functional currency.

The SEC and the Financial Accounting Standards Board, or FASB have issued recent interpretations for U.S. GAAP that suggest warrants with exercise prices denominated in a different currency from the entity’s functional currency cannot be classified as equity. As a result, these

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instruments would be treated as derivatives and recorded as liabilities which are carried at their fair value, with period to period changes in the fair value recorded as a gain or loss in the statement of operations.

In November 2007, the Emerging Issues Task Force or EITF issued EITF No. 07-5, Issue Summary No.1 “Determining Whether an Instrument (or an Embedded Feature) is Indexed to an Entity’s Own Stock”. The Issue Summary discusses the merits of various accounting treatments related to this issue but does not provide any definitive guidance. The EITF considers Issue 07-5 an open issue subject to further discussion at future meetings.

If we had recorded such instruments as derivatives, we would have reported a loss of approximately $50 and $9,452 for the fiscal year ended December 31, 2007 and 2006, respectively and a gain of $7,592 for the fiscal year ended December 31, 2005. We calculated the amounts using the Black-Scholes option pricing model and used the following assumptions: volatility rate of 80%, 70% and 70% for fiscal years ended December 31, 2007, 2006 and 2005, respectively; the actual exercise price of each instrument at December 31, 2007, 2006 and 2005; the stock price at December 31, 2007, 2006 and 2005 and the Canadian risk free interest rate for the remaining life of the related warrants; and a 0% dividend rate for all fiscal years.

Outstanding Share Information

The outstanding share data for the Company as of December 31, 2007 is as follows (in thousands):

Canadian Accounting Principles

We present our consolidated financial results in accordance with U.S. GAAP. Significant differences exist between U.S. and Canadian GAAP and are presented in Note 15 in the consolidated financial statements.

Recent Accounting Pronouncements

In June 2007, the Emerging Issues Task Force, or EITF, issued EITF No. 07-3, “Accounting for Nonrefundable Advance Payments for Goods or Services to Be Used in Future Research and Development Activities”, or EITF 07-3, which provides guidance for up-front payments related to goods and services of research and development costs. EITF 07-3 is effective for fiscal years beginning after December 15, 2007. We are currently evaluating the impact of EITF 07-3 on our financial statements but do not anticipate a material impact.

In February 2007, the Financial Accounting Standards Board, or FASB, issued SFAS No. 159, “The Fair Value Option for Financial Assets and Financial Liabilities—including an amendment of FASB Statement No. 115”, or SFAS 159, which is effective for fiscal years beginning after November 15, 2007. SFAS 159 permits companies to choose to measure many financial instruments and certain other items at fair value on a per instrument basis, with changes in fair value recognized in earnings each reporting period. This will enable some companies to reduce volatility in reported earnings caused by measuring related assets and liabilities differently. SFAS 159 also establishes presentation and disclosure requirements designed to facilitate comparisons between companies that choose different measurement attributes for similar types of assets and liabilities. We are currently evaluating the impact, if any, that adopting SFAS 159 will have on our results of operations and financial condition.

In July 2006, the Financial Accounting Standards Board issued Interpretation No. 48 (“FIN 48”), “Accounting for Uncertainty in Income Taxes – an Interpretation of SFAS No. 109.” FIN 48 clarifies the accounting for uncertainty in income taxes recognized in an enterprise’s financial statements in accordance with Statement of Financial Accounting Standards No. 109, “Accounting for Income Taxes.” FIN 48 also prescribes a recognition threshold and measurement of a tax position taken or expected to be taken in an enterprise’s tax return. We adopted FIN 48, as required, effective January 1, 2007. The adoption of FIN 48 did not have any impact on our consolidated financial position or results of operations.

In September 2006, the FASB issued SFAS No. 157, “Fair Value Measurements”, or SFAS 157. SFAS 157 establishes a framework for measuring fair value, and expands disclosures about fair value measurements. The statement is effective for financial statements issued for fiscal years beginning after November 15, 2007, and interim periods within that fiscal year. On February 12, 2008, the FASB approved the Financial Staff Position, or FSP, No. SFAS 157-2, “Effective Date of FASB Statement No. 157”, or FSP FAS 157-2, which delays the effective date of SFAS 157 to fiscal years beginning after November 15, 2008, and interim periods within those fiscal years for non-financial assets and non-financial liabilities, except for those items that are recognized or disclosed at fair value in the financial statements on a recurring basis (at least annually). We are currently evaluating the impact, if any, that adopting SFAS 157 will have on our results of operations and financial condition.

In December, 2007, the FASB issued SFAS No. 141(R), “Business Combinations”, or SFAS 141(R), which applies prospectively to business combinations for which the acquisition date is on or after the beginning of the first annual reporting period beginning on or after December 15, 2008. SFAS 141(R) establishes principles and requirements for how the acquirer: i) recognizes and measures in its financial statements the identifiable assets acquired, the liabilities assumed and any noncontrolling interest in the acquiree; ii) recognizes and measures the goodwill acquired in the business combination or a gain from a bargain purchase; and iii) determines what information to disclose to enable users of the financial statements

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to evaluate the nature and financial effects of the business combination. We do not expect the adoption of SFAS 141 (R) to have an effect on our results of operations and financial condition unless we enter into a business combination after January 1, 2009.

Foreign Exchange Risk

Currently the Company’s principal operations are located in the United States. At December 31, 2007, we had approximately $16.2 million in cash and cash equivalents. To date, derivative financial instruments have not been needed or used. Security of principal versus income historically governed investment decisions, with excess funds invested in short term, government backed securities or bankers acceptances.

At December 31, 2007, we held approximately CAD$1.5 million of cash to fund certain research and development activities in Canada. At this time we do not utilize derivative financial instruments. Should business conditions dictate, we may consider the use of derivative instruments in the future. However, security of principal versus income generation will continue to govern investment decisions.

The financial statements required to be filed pursuant to this Item 8 are appended to this Annual Report on Form 10-K. A list of the financial statements file herewith is found at “Index to Financial Statements” on Page F-1.

None.

Conclusion Regarding the Effectiveness of Disclosure Controls and Procedures

Disclosure controls and procedures (as defined in Exchange Act Rule 13a-15(e)) are designed only to provide reasonable assurance that information to be disclosed in our Exchange Act Reports is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms. As of the end of the period covered by this report, the Company carried out an evaluation, under the supervision and with the participation of the Company’s management, including the Company’s Chief Executive Officer and Chief Financial Officer, of the effectiveness of the Company’s disclosure controls and procedures pursuant to Exchange Act Rule 13a-15(e). Based upon this evaluation, the Company’s Chief Executive Officer and Chief Financial Officer have concluded that our disclosure controls and procedures are effective to provide the reasonable assurance discussed above.

Management’s Report on Internal Control over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Exchange Act Rule 13a-15(f). Our internal control over financial reporting is designed to provide reasonable assurance to our management and board of directors regarding the preparation and fair presentation of published financial statements. A control system, no matter how well designed and operated, can only provide reasonable, not absolute, assurance that the objectives of the control system are met and must reflect the fact that there are resource constraints that require management to consider the benefits of internal controls relative to their costs. Because of these inherent limitations, management does not expect that our internal controls over financial reporting can prevent all error and all fraud. Under the supervision and with the participation of our management, including our Chief Executive Officer and our Chief Financial Officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting based on the framework found in Internal Control – Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on our evaluation under the framework found in Internal Control – Integrated Framework, our management concluded that our internal control over financial reporting was effective as of December 31, 2007.

Changes in Internal Control over Financial Reporting

There was no change in our internal controls over financial reporting during the fourth quarter of the period covered by this Annual Report that has materially affected, or is reasonably likely to materially affect, our internal controls over financial reporting.

None.

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PART III

Information required by this Item concerning our directors is incorporated by reference from the section captioned “Election of Directors” contained in our proxy statement related to the 2008 Annual General Meeting of Stockholders scheduled to be held on May 14, 2008, which we intend to file with the SEC within 120 days of the end of our fiscal year pursuant to General Instruction G(3) of Form 10-K.

The Board of Directors has determined that the members of the Audit Committee are independent as defined in Rule 4200(a)(15) of the National Association of Securities Dealers’ listing standards. The Board of Directors has also determined that Dr. Arthur T. Porter is an “audit committee financial expert” as defined in Item 401(h) of Regulation S-K.

Our Board of Directors adopted a code of business conduct and ethics that applies to all of our directors and employees, including our Chief Executive Officer, Chief Financial Officer, Chief Accounting Officer and Controller, or persons performing similar functions. We will provide copies of our code of business conduct and ethics without charge upon request. To obtain a copy, please send your written request to Adherex Technologies Inc., 4620 Creekstone Drive, Suite 200, Durham, NC 27703, Attention: Secretary. In addition, you can find the code on our website under the Investors Relations section at www.adherex.com.

The information required by this Item concerning executive officers of the Registrant is set forth at the end of Part I of this report.

The information required by this Item concerning compliance with Section 16(a) of the United States Securities Exchange Act of 1934, as amended, is incorporated by reference from the section of the proxy statement captioned “Report on Corporate Governance—Section 16(a) Beneficial Ownership Reporting Compliance.”

The information required by this Item is incorporated by reference from the sections captioned “Executive Compensation” and “Compensation of Directors” contained in the proxy statement.

Equity Compensation Plan Information

The following table provides certain information with respect to securities authorized for issuance under equity incentive plans as of December 31, 2007:

The other information required by this Item is incorporated by reference from the section captioned “Voting Securities and Principal Holders of Voting Securities” contained the proxy statement.

The information required by this Item is incorporated by reference from the section captioned “Other Information Regarding Management – Interest of Informed Persons in Material Transactions” and “Report on Corporate Governance – Board of Directors” contained in the proxy statement.

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The information required by this Item is incorporated by reference from the section captioned “Report on Corporate Governance – Other Board Committees – Audit Committee Report” contained in the proxy statement.

PART IV

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