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News Release

Cyclacel Pharmaceuticals reports preclinical Seliciclib-Erlotinib synergy data at AACR

Apr 17 2007

Cyclacel Pharmaceuticals reports preclinical Seliciclib-Erlotinib synergy data at AACR

BERKELEY HEIGHTS, NJ, April 17, 2007 – Cyclacel Pharmaceuticals, Inc. (Nasdaq: CYCC) (Nasdaq: CYCCP) announced today preclinical results from a combination study of seliciclib, an orally-available cyclin dependent kinase (CDK) inhibitor, with epidermal growth factor receptor (EGFR) inhibitor erlotinib (Tarceva®). The study demonstrated that the drugs act synergistically in suppressing tumor growth in models of non-small cell lung cancer (NSCLC). The data, presented as a poster (#4003) at the Annual Meeting of the American Association for Cancer Research (AACR) in Los Angeles, is part of the company’s broad program to assess the potential of seliciclib. Currently, seliciclib is being evaluated in a Phase II randomized double-blinded clinical trial as a single agent in NSCLC.

In two animal models of NSCLC the combination of seliciclib and erlotinib was more effective in suppressing tumor growth than either drug alone. The combination reduced EGFR signaling and synergistically induced death by apoptosis in cancer cells. Administration of the combination over a 28 day period induced tumor growth inhibition (TGI) of 93% for 49 days (p<0.0001) with tumor growth inhibition continuing up to the experimental endpoint (TGI of 73% on Day 74).

Biomarker analysis showed a significant decrease in the levels of cyclin D1 in tumor cells treated by the combination of the two drugs while treatment with either drug alone had minimal effect on cyclin D1 levels. Overexpression of cyclin D1 is one of the most frequently found abnormalities in human cancers and is known to correlate with the early onset of cancer and risk of tumor progression and metastasis. In most cancer types, including lung, breast, colon and sarcoma, cyclin D1 overexpression results from induction by oncogenic signals, such as ErbB2 and Ras. The mechanism underlying the observed synergy remains to be elucidated.

Abstract No: 4003

About Cyclacel Pharmaceuticals, Inc.
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 lung cancer. Sapacitabine (CYC682), an orally-available, cell cycle modulating nucleoside analog, is in Phase I clinical trials for the treatment of solid and hematological cancers. CYC116, an orally-available, Aurora kinase and VEGFR2 inhibitor, is at the IND stage. Several additional programs are at an earlier stage.

About seliciclib
Seliciclib is an orally-available cyclin dependent kinase (CDK) inhibitor that selectively inhibits multiple enzyme targets, CDK2/E, CDK2/A, CDK7 and CDK9, that are central to the process of cell division and cell cycle control. Seliciclib has been evaluated in approximately 250 patients, including patients with advanced NSCLC in which seliciclib was administered in combination with gemcitabine and cisplatin as first-line treatment and with docetaxel as second-line treatment. Seliciclib is currently being evaluated as a third-line treatment for Non-Small Cell Lung Cancer (NSCLC) in the Phase IIb, multi-center, randomized, double-blinded “APPRAISE” trial with the goal of generating a strong signal of activity in terms of Progression Free Survival. Cyclacel also intends to initiate a Phase II trial of seliciclib as a treatment for patients with nasopharyngeal cancer (NPC), a disease associated with Epstein-Barr Virus infection, in the second half of 2007.

Please visit http://www.cyclacel.com/cyc/investors/news/pressreleases/ for additional information on the above highlights.

Note: The Cyclacel logo and Cyclacel® are trademarks of Cyclacel Pharmaceuticals, Inc.

Risk Factors
This news release contains certain forward-looking statements that involve risks and uncertainties that could cause actual results to be materially different from historical results or from any future results expressed or implied by such forward-looking statements. Such forward-looking statements include statements regarding, among other things, the efficacy, safety, and intended utilization of Cyclacel’s product candidates, the conduct and results of future clinical trials, plans regarding regulatory filings, future research and clinical trials and plans regarding partnering activities. Factors that may cause actual results to differ materially include the risk that product candidates that appeared promising in early research and clinical trials do not demonstrate safety and/or efficacy in larger-scale or later clinical trials, the risk that Cyclacel will not obtain approval to market its products, the risks associated with reliance on outside financing to meet capital requirements, and the risks associated with reliance on collaborative partners for further clinical trials, development and commercialization of product candidates. You are urged to consider statements that include the words "may," "will," "would," "could," "should," "believes," "estimates," "projects," "potential," "expects," "plans," "anticipates," "intends," "continues," "forecast," "designed," "goal," or the negative of those words or other comparable words to be uncertain and forward-looking. These factors and others are more fully discussed under "Risk Factors" in the registration statement on Forms S-3 (File No. 333-134945) and S-4 (File No. 333-131225) and in the other reports of Cyclacel filed with the SEC.

Contacts for Cyclacel:

For Investors:
TS Communications Group, LLC (914) 921-5900
Tara Spiess / Andrea Romstad
For Media:
Feinstein Kean Healthcare (617) 577-8110
Robert Gottlieb / Kate Weiss