5-FU Expert Presents Data Supporting Adherex's Approach to Development of Eniluracil.

RESEARCH TRIANGLE PARK, N.C. -- Adherex Technologies Inc. (AMEX:ADH)(TSX:AHX), a biopharmaceutical company with a broad portfolio of oncology products under development, today announced that Dr. Robert B. Diasio, Chairman, Department of Pharmacology and Toxicology at the University of Alabama School of Medicine in Birmingham, Alabama and Associate Director for Basic Sciences, UAB Comprehensive Cancer Center, presented data in Edinburgh, Scotland at the January 19th PAMM (Pharmacology and Molecular Mechanisms) Meeting of the European Organization for Research and Treatment of Cancer (EORTC), which supports Adherex's development plans for eniluracil.

"These data provide direct evidence that eniluracil can affect one of the critical enzymes involved in the anabolic pathway for 5-FU," said Dr. Diasio. "This implies that using the correct schedule and dose ratio of eniluracil in combination with 5-FU becomes very important for optimizing 5-FU anti-tumor activity."

The research presented by Dr. Diasio involved direct measurements of enzyme activity in human kidney cells and demonstrated that at a 2.5 to 1 ratio of eniluracil to 5-FU, uridine phosphorylase, a major enzyme involved in the activation of 5-FU, is approximately 50% inhibited, and that this inhibition is dose dependent. Therefore, eniluracil not only irreversibly inhibits the enzyme dihydropyrimidine dehydrogenase (DPD) which breaks down 5-fluorouracil (5-FU), it can also reversibly inhibit the activation of 5-FU, thereby limiting the effectiveness of 5-FU as an anti-cancer agent when not dosed properly.

Adherex in-licensed eniluracil from GlaxoSmithKline (GSK) in July 2005. While in development by GSK, three Phase III trials of the combination of eniluracil and 5-FU failed. However, last November, Adherex announced that the Company had produced data indicating that the high 10 to 1 ratio of eniluracil to 5-FU used in these prior clinical studies may have been responsible for their failure and that correcting the dose ratio and/or increasing the interval between the eniluracil and 5-FU administration may improve the clinical result.

About Adherex Technologies

Adherex Technologies Inc. is a biopharmaceutical company dedicated to the discovery and development of novel cancer therapeutics. We aim to be a leader in developing innovative treatments that address important unmet medical needs in cancer. We currently have multiple products in the clinical stage of development, including ADH-1 (Exherin(TM)), eniluracil and sodium thiosulfate (STS). ADH-1, our lead biotechnology compound, selectively targets N-cadherin, a protein present on certain tumor cells and established blood vessels that feed solid tumors. Eniluracil, an oral dihydropyrimidine dehydrogenase (DPD) inhibitor, was previously under development by GlaxoSmithKline for oncology indications. STS, a drug from our specialty pharmaceuticals pipeline, protects against the disabling hearing loss that can often 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 is emerging as a pioneering oncology company. 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 results of such development. We can provide no assurance that the expected results of such development will be realized. We are subject to various risks, including those inherent in the biopharmaceutical industry, the early stage of our product candidates, the uncertainties of drug development, clinical trials and regulatory review, our reliance on collaborative partners, our need for additional capital to fund our operations, and our history of losses. For a more detailed discussion of related risk factors, please refer to our public filings available at www.sedar.com and www.sec.gov.

ADHEREX TECHNOLOGIES INC. (TSX:AHX) (AMEX:ADH)