Cytokinetics, Inc. Announces Clinical And Non-Clinical Data On Ispinesib To Be Presented At The 2005 AACR-NCI-EORTC International Meeting

SOUTH SAN FRANCISCO, Calif., Nov. 10 /PRNewswire-FirstCall/ -- Cytokinetics, Incorporated announced today that data from Phase Ib combination clinical trials and non-clinical studies of ispinesib (SB-715992) will be presented at the 2005 AACR-NCI-EORTC International Conference in Philadelphia, Pennsylvania. The two clinical poster presentations will highlight data from two Phase Ib combination clinical trials, one evaluating ispinesib in combination with capecitabine and the other evaluating ispinesib in combination with docetaxel. The Phase Ib combination clinical trials were designed to assess the safety, tolerability and pharmacokinetics of ispinesib in combination with the standard chemotherapeutics, and to determine the optimally tolerated regimen of ispinesib in combination with each of the two drugs. In addition, four poster presentations describing the further non-clinical characterization of ispinesib, including data relating to resistance mechanisms, pharmacodynamic markers, potential therapeutic index and suitability for combination with cisplatin, will also be presented.

Poster Presentations at AACR-NCI-EORTC International Conference

The following posters will be presented at the AACR-NCI-EORTC International Conference:

Phase Ib Combination Clinical Trial Posters: Poster C80: Phase I Study of Ispinesib in Combination with Docetaxel in Patients with Advanced Solid Tumors Poster C85: Phase I Study of Ispinesib in Combination with Capecitabine in Patients with Advanced Solid Tumors Non-Clinical Posters: Poster C196: Mitotic Arrest in Tumors as a Pharmacodynamic Marker for Inhibition of the Mitotic Kinesin KSP by Ispinesib, a Novel KSP Inhibitor Poster C203: Relationship Between the Antitumor Activity of Ispinesib, a Novel KSP inhibitor, and Neutropenia in a Human Xenograft Model Poster C204: Cisplatin Enhances the Activity of Ispinesib, a Novel KSP inhibitor, Against Murine P388 Lymphocytic Leukemia Poster C207: A Resistance Mechanism for the KSP Inhibitor Ispinesib Implicates Point Mutations in the Compound Binding Site

All posters will be presented during Poster Session C on Thursday, November 17, 2005 between 12:30 PM-2:30 PM ET and 5:30 PM-7:30 PM ET, in Hall C, Pennsylvania Convention Center.

About Ispinesib

Ispinesib is a novel small molecule inhibitor of Kinesin Spindle Protein (KSP), a mitotic kinesin protein essential for proper cell division. Ispinesib is the first drug candidate in clinical development that has arisen from a broad strategic collaboration between Cytokinetics and GlaxoSmithKline (GSK) to discover, develop and commercialize novel small molecule therapeutics targeting human mitotic kinesins for applications in the treatment of cancer and other diseases. GSK is conducting a broad clinical trials program for ispinesib designed to study the drug candidate in multiple tumor types, combination regimens and dosing schedules. GSK is currently evaluating ispinesib in three Phase II studies being conducted in patients with each of non-small cell lung, ovarian and breast cancers and three Phase Ib clinical trials designed to evaluate ispinesib in combination with each of docetaxel, carboplatin and capecitabine. Interim data from the ongoing breast cancer clinical trial and the platinum-refractory treatment arm of the non-small cell lung cancer clinical trial were announced recently. In the Phase II clinical trial enrolling patients with advanced breast cancer, the best overall responses observed with ispinesib administered as monotherapy have been partial responses in three of thirty-three evauable patients to date. Interim data from this ongoing breast cancer trial will be presented on December 8, 2005 at the San Antonio Breast Cancer Symposium in San Antonio, Texas. In the platinum-refractory treatment arm of a Phase II trial enrolling patients with non-small cell lung cancer, the best overall response observed with ispinesib administered as monotherapy has been disease stabilization in 25% (N=20) of patients with a median time to progression (TTP) of 12 weeks (overall median TTP was 6 weeks). In addition to the ongoing studies being conducted by GSK, the National Cancer Institute (NCI) continues to enroll patients in five other Phase II clinical trials evaluating ispinesib in other tumor types, including melanoma, head and neck, hepatocellular, colorectal and prostate cancers. In addition, the NCI plans to conduct one additional Phase II clinical trial in patients with renal cell carcinoma. The NCI is also conducting two other Phase I clinical trials evaluating an alternative schedule of ispinesib in leukemia and advanced solid tumors.

About Cytokinetics

Cytokinetics is a leading biopharmaceutical company focused on the discovery, development and commercialization of novel small molecule drugs that specifically target the cytoskeleton. The cytoskeleton is a complex biological infrastructure that plays a fundamental role within every human cell. Cytokinetics’ focus on the cytoskeleton enables it to develop novel and potentially safer and more effective classes of drugs directed at treatments for cancer, cardiovascular disease and other diseases. Cytokinetics has developed a cell biology driven approach and proprietary technologies to evaluate the function of many interacting proteins in the complex environment of the intact human cell. Cytokinetics employs the PUMA(TM) system and Cytometrix(TM) technologies to enable early identification and automated prioritization of compounds that are highly selective for their intended protein targets without other cellular effects, and may therefore be less likely to give rise to clinical side effects. Cytokinetics and GlaxoSmithKline have entered into a strategic alliance to discover, develop and commercialize small molecule therapeutics targeting human mitotic kinesins for applications in the treatment of cancer and other diseases. GlaxoSmithKline is conducting Phase II and Phase Ib clinical trials for ispinesib (SB-715992) and a Phase I clinical trial for SB-743921, each a drug candidate that has emerged from the strategic alliance. Cytokinetics’ heart failure program is the second program to leverage the company’s expertise in cytoskeletal pharmacology. Cytokinetics recently initiated a Phase I human clinical trial with CK-1827452, a novel small molecule cardiac myosin activator, for the treatment of heart failure. Additional information about Cytokinetics can be obtained at

This press release contains forward-looking statements for purposes of the Private Securities Litigation Reform Act of 1995 (the “Act”). Cytokinetics disclaims any intent or obligation to update these forward-looking statements, and claims the protection of the Safe Harbor for forward-looking statements contained in the Act. Examples of such statements include, but are not limited to, statements relating to the expected timing, scope and results of our and our partners’ clinical development and research program, including, initiation of clinical trials, statements regarding future presentations concerning our and our partners’ research and development program and data from clinical trials, and statements regarding the potential benefits of our drug candidates and potential drug candidates and the enabling capabilities of our proprietary technologies. Such statements are based on management’s current expectations, but actual results may differ materially due to various factors. Such statements involve risks and uncertainties, including, but not limited to, those risks and uncertainties relating to difficulties or delays in development, testing, regulatory approval, production and marketing of Cytokinetics’ drug candidates that could slow or prevent clinical development, product approval or market acceptance (including the risks relating to uncertainty of patent protection for Cytokinetics’ intellectual property or trade secrets, Cytokinetics’ ability to obtain additional financing if necessary and unanticipated research and development and other costs). For further information regarding these and other risks related to Cytokinetics’ business, investors should consult Cytokinetics’ filings with the Securities and Exchange Commission.

Cytokinetics, Incorporated

CONTACT: Robert I. Blum, EVP, Corporate Development and CommercialOperations & CBO of Cytokinetics, Incorporated, +1-650-624-3000; orinvestors, Clay Kramer, +1-212-213-0006, or media, Justin Jackson,+1-212-213-0006, both of Burns McClellan, Inc., for Cytokinetics,Incorporated