HAYWARD, Calif., April 3 /PRNewswire-FirstCall/ -- Kosan Biosciences Incorporated will present data today on KOS-953 and KOS-1022, two drug candidates in its Hsp90 (heat shock protein 90) inhibitor program, as well as KOS-1584, its second-generation epothilone, at the 97th Annual Meeting of the American Association of Cancer Research (AACR) in Washington, D.C. In addition, Kosan will report on its development of a series of nuclear-export inhibitors, a novel class of compounds with potential as anti-cancer therapeutics, in a late-breaking session on Tuesday, April 4th.
KOS-953 - Phase Ib Clinical Study in Combination with Trastuzumab
In the presentation “Phase 1 Dose-Escalating Trial of KOS-953 and Trastuzumab,” Abstract # 2919, Kosan reported primarily on the pharmacokinetics and pharmacodynamics of escalating doses of KOS-953 administered in combination with trastuzumab (Herceptin(R)) in 25 patients. In evaluating the pharmacokinetics of KOS-953, exposure increased linearly with dose. Importantly, the pharmacokinetics of trastuzumab were not altered by KOS-953. The recommended dose for future study was set at 450 mg/m2, and enrollment in the Phase II portion of the clinical trial is ongoing in order to determine the clinical activity of this combination.
KOS-1022, Oral Formulation - Preclinical Data
In the poster “Pharmacokinetics and Toxicology of KOS-1022, an Orally Administered Heat Shock Protein 90 (Hsp90) Inhibitor,” Abstract #3093, preclinical data on the oral formulation of KOS-1022, Kosan’s second-generation Hsp90 inhibitor, were presented. Toxicology data in the rat and dog defined the maximum tolerated dose of the compound and established the starting dose for the Phase I clinical trial, now ongoing, at 5 mg administered every other day. The Phase I clinical trial in patients with advanced solid tumors is proceeding and has generated data indicating good bioavailability.
KOS-1584 - Preclinical Data
The third poster presentation, “Tissue Distribution and Pharmacokinetics for KOS-1584: A Rationally Designed Microtubule Polymerization Stabilizer,” Abstract # 3098, highlighted preclinical data on KOS-1584, Kosan’s second-generation epothilone. The data demonstrated that in an animal model, high concentrations of KOS-1584 are achieved in tumor tissue; these concentrations are maintained over time, and at higher levels compared with other tissues. Pharmacokinetic data in animals have been predictive of those observed to date in humans in two ongoing Phase I clinical trials where there is larger volume of distribution and longer half-life of KOS-1584 relative to the first generation epothilone, KOS-862.
About Kosan
Kosan Biosciences is a biotechnology company advancing two new classes of anticancer agents through clinical development. Its heat shock protein 90, or Hsp90, inhibitor, KOS-953, is in Phase I and II clinical trials, primarily for multiple myeloma and HER2 positive breast cancer. KOS-953 is Kosan’s proprietary formulation of 17-AAG, a geldanamycin analog. In addition, intravenous and oral formulations of its second-generation Hsp90 inhibitor, KOS-1022, are currently in Phase I clinical trials. These compounds have a novel mechanism of action targeting multiple pathways involved in cancer cell growth and survival.
Kosan is also developing KOS-862 in Phase II clinical trials in breast cancer. KOS-862 is an epothilone with a mechanism of action similar to taxanes, one of the most successful classes of anti-tumor agents. Its follow-on epothilone, KOS-1584, is in Phase I clinical trials. Its epothilone program is partnered with Hoffmann-La Roche, Inc. and F. Hoffmann-La Roche Ltd., collectively Roche, through a global development and commercialization agreement. For additional information on Kosan Biosciences, please visit the company’s website at www.kosan.com.
This press release contains forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995 (the “Act”). Such forward-looking statements include statements relating to the further development and potential safety and efficacy of KOS-953, KOS-1022 and KOS-1584 in the treatment of cancer. Any statements contained in this press release that are not statements of historical fact may be deemed to be forward-looking statements. There are a number of important factors that could cause the results of Kosan to differ materially from those indicated by these forward-looking statements, including, among others, risks related to the clinical advancement of Kosan’s product candidates, including the risk that clinical trials may not demonstrate safety and efficacy sufficient to obtain the requisite regulatory approvals or to result in a marketable product and other risks detailed from time to time in the Company’s SEC reports, including its Annual Report on Form 10-K for the year ended December 31, 2005 and other periodic filings with the SEC. Kosan does not undertake any obligation to update forward-looking statements.
NOTE: Herceptin(R) (trastuzumab) is a registered trademark of Genentech, Inc., and Velcade(R) (bortezomib) is a registered trademark of Millennium Pharmaceuticals, Inc.
Kosan Biosciences Incorporated
CONTACT: Robert G. Johnson, Jr., M.D., Ph.D., Chief Executive Officer ofKosan Biosciences, +1-510-732-8400, ext. 5243, or johnson@kosan.com
Web site: http://www.kosan.com//
