Seliciclib (CYC202) Shown To Kill Multiple Myeloma Cells

San Diego, California - 7 December 2004 - Cyclacel Group plc (“Cyclacel”), the UK-based biopharmaceutical company, announced that a poster presented by independent investigators at the American Society for Hematology (ASH) meeting reported that seliciclib (CYC202 or R-roscovitine) killed multiple myeloma cancer cells by causing them to commit suicide. Seliciclib is Cyclacel’s leading Cyclin Dependent Kinase (CDK) inhibitor drug.

Researchers at Dana Farber Cancer Institute and Harvard Medical School reported their findings that seliciclib had potent cytotoxic effects against nine different multiple myeloma cell lines removed from patients with multiple myeloma that were both sensitive and resistant to conventional chemotherapy. The drug appeared to induce myeloma cells to commit suicide through apoptosis by blocking the production of a protein that is required for cancer cell survival. The investigators concluded that their study provided pre-clinical support for a clinical trial of seliciclib, either alone or in combination with other agents with the objective of improving patient outcomes in multiple myeloma.

Seliciclib is currently in Phase II clinical trials as a single therapy in multiple myeloma as well as two other B-cell hematological malignancies: B-cell Chronic Lymphocytic Leukemia (B-CLL) and Mantle Cell Lymphoma. An additional Phase II clinical trial is in progress investigating the effects of seliciclib in patients with Non-Small Cell Lung Cancer in combination with gemcitabine and cisplatin.

Spiro Rombotis, Chief Executive Officer of Cyclacel, said: “Independent investigators continue to validate our belief that our CDK inhibitor drug seliciclib may be useful in certain blood cancers, such as multiple myeloma. These cancers are likely caused by abnormal genetic mechanisms that are affected by the action of seliciclib. We are using advanced biomarker technologies together with clinical trial results to better define the population of patients most likely to benefit from our drug and how to best use it either alone or as part of combination therapy.”

About Cyclacel ( www.cyclacel.com )
Cyclacel is a biopharmaceutical company dedicated to the discovery, development and commercialization of novel, mechanism-targeted drugs to treat human cancers and other serious disorders. The company is currently evaluating seliciclib (CYC202), an orally-available cyclin dependent kinase inhibitor, in Phase II clinical trials for the treatment of non-small cell lung cancer and B-cell hematological malignancies. CYC682 is an orally-available, cell cycle modulating nucleoside analog in Phase I clinical trials for the treatment of cancer. Cyclacel also has seven programs in preclinical development.

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