Adherex Announces Publication of ADH-1 Study In Cancer Research

Research Triangle Park, NC, May 15, 2008 - Adherex Technologies Inc. (AMEX:ADH, TSX:AHX), a biopharmaceutical company devoted to solving problems for patients with cancer, announced today that the results of a preclinical study of ADH-1 in combination with chemotherapy were published in the May issue of Cancer Research.  The study, entitled “Targeting N-Cadherin Enhances Antitumor Activity of Cytotoxic Therapies in Melanoma Treatment,â€�¹ was conducted by Dr. Douglas Tyler and colleagues at the Duke Comprehensive Cancer Center.

In the study, the researchers noted a 30-fold reduction in tumor size following treatment with ADH-1 and melphalan chemotherapy compared to the chemotherapy alone.  The combination of ADH-1 and melphalan produced frequent, durable and complete tumor regression in the human xenograft melanoma models.  In addition to the significant synergy, ADH-1 in combination with melphalan was also shown to produce responses in tumors resistant to melphalan, where neither agent alone produced tumor regression.

“We tested ADH-1, a compound that can weaken the tumor by targeting the N-cadherin expressed on the surface of a melanoma cell, in combination with chemotherapy.  When chemotherapy was applied to the tumor in this weakened state, it was much more effective compared to conventional therapy alone,â€� said Douglas Tyler, M.D., a surgeon at Duke and the Durham Veterans Affairs Medical Center, and senior investigator on this study. “These results are extremely significant because they may help us better treat patients with this deadly condition.â€�

Tyler continued, “We saw a complete regression of the tumors in the animal model when we used the regional melphalan chemotherapy in combination with ADH-1, which is far better than anything we have seen before with the chemotherapy alone.  Furthermore, the addition of ADH-1 produced no additional side effects, which is an important consideration in cancer treatment.â€�

The synergy observed in the study has led Adherex to rapidly move into clinical studies where we are evaluating ADH-1 in combination with melphalan via isolated limb infusion for the treatment of melanoma in an ongoing multi-institutional Phase I/IIB trial.  Current participating centers include Duke University Medical Center, MD Anderson Cancer Center, Lehigh Valley Hospital and H. Lee Moffitt Cancer Center, with plans to add up to four additional centers.  The trial is expected to enroll a total of 56 patients, and has already accrued 33 patients to date.  

The results of the Phase I and initial Phase IIB data from this study will be presented at the 2008 American Society of Clinical Oncology (ASCO) Annual Meeting, which takes place May 30 - June 3, 2008 in Chicago, IL.  The poster discussion presentation entitled "A phase I/II study of systemic ADH-1 in combination with isolated limb infusion with melphalan (ILI-M) in patients with locally advanced in-transit melanoma" is scheduled to be presented on June 1, 2008.

Earlier this year, Adherex was granted orphan drug designation for the use of ADH-1 in conjunction with melphalan for the treatment of Stage IIB/C, III, and IV malignant melanoma.

¹ Augustine CK, Yoshimoto Y, Gupta M, Zipfel PA, Selim MA, Febbo P, Pendergast AM, Peters WP, Tyler DS: Targeting N-Cadherin Enhances Antitumor Activity of Cytotoxic Therapies in Melanoma Treatment. Cancer Res 2008; 68(10); 1-8.

About Adherex Technologies

Adherex Technologies Inc. is a biopharmaceutical company dedicated to the discovery and development of novel cancer therapeutics. We are in the business of solving problems for patients with cancer.  We have multiple products in the clinical stage of development, including eniluracil, ADH-1 and sodium thiosulfate (STS).  Eniluracil, an oral dihydropyrimidine dehydrogenase (DPD) inhibitor, is being developed to improve the tolerability and effectiveness of 5-fluorouracil (5-FU), one of the most widely used oncology drugs in the world. ADH-1 is a biotechnology compound which selectively targets N-cadherin, a protein present on certain tumor cells and the blood vessels of solid tumors. STS is a chemoprotectant being developed to reduce or prevent hearing loss that may result from treatment with platinum-based chemotherapy drugs. With a diversified portfolio of unique preclinical and clinical-stage cancer compounds and a management team with expertise in identifying, developing and commercializing novel cancer therapeutics, Adherex aims to become a leader in developing innovative treatments that address important unmet medical needs in cancer. For more information, please visit our website at www.adherex.com.

This press release contains forward-looking statements that involve significant risks and uncertainties.  The actual results, performance or achievements of the Company might differ materially from the results, performance or achievements of the Company expressed or implied by such forward-looking statements.  Such forward-looking statements include, without limitation, those regarding the development plans of the Company and the expected timing or results of our development.  We can provide no assurance that such development will proceed as currently anticipated or that the expected timing or results of such development will be realized.  We are subject to various risks, including the uncertainties of clinical trials, drug development and regulatory review, the early stage of our product candidates, our reliance on collaborative partners, our need for additional capital to fund our operations, our history of losses, and other risks inherent to the biopharmaceutical industry.  For a more detailed discussion of related risk factors, please refer to our public filings available at www.sedar.com and www.sec.gov.

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For further information, please contact:

D. Scott Murray
Senior Vice President, Corporate Development
Adherex Technologies Inc.
T: (919) 484-8484
info@adherex.com