Kosan Names Its Lead Hsp90 Inhibitor Compounds
Tuesday August 22, 7:30 am ET
HAYWARD, Calif., Aug. 22 /PRNewswire-FirstCall/ -- Kosan Biosciences Incorporated (Nasdaq: KOSN - News) announced the selection of nonproprietary compound names for its two lead Hsp90 inhibitor compounds. KOS-953 is named tanespimycin and KOS-1022 is named alvespimycin hydrochloride. The compound names have been adopted by the United States Adopted Names (USAN) Council and the World Health Organization (WHO).
Tanespimycin is the most advanced Hsp90 inhibitor in clinical trials. The compound is in a Phase Ib trial in combination with Velcade® for multiple myeloma, and is in a Phase I trial as a single agent in multiple myeloma. Tanespimycin is also being evaluated in a Phase II combination trial with Herceptin® for breast cancer, and in a Phase II single-agent trial in melanoma. Kosan's potential registration strategy for tanespimycin is for treatment of multiple myeloma in combination with Velcade in first relapsed patients. In the Phase Ib trial of tanespimycin plus Velcade, some patients who previously failed on Velcade have responded to treatment with the combination, providing another potential treatment option for refractory patients. Kosan could potentially initiate a Phase II/III registrational development program for tanespimycin in the late 2006-early 2007 timeframe. Tanespimycin has been granted orphan drug status in multiple myeloma in the US and in Europe.
Alvespimycin hydrochloride, Kosan's second-generation Hsp90 inhibitor, has shown enhanced potency and ease of formulation with potentially more favorable dosing for solid tumors. Intravenous and oral formulations of alvespimycin are being evaluated in Phase I trials and intravenous alvespimycin is also being evaluated in a Phase I/II trial in combination with Herceptin. The company also anticipates evaluating alvespimycin in combination with Herceptin plus a taxane in metastatic breast cancer.
"Kosan has built an industry-leading position in Hsp90 inhibitors," said Robert G. Johnson, Jr., M.D., Ph.D., Kosan's Chief Executive Officer. "Our first and second generation compounds are demonstrating potent antitumor activity in multiple tumor types. We believe that tanespimycin and alvespimycin represent important new approaches to treating cancer due to their novel mechanism of action and potential to overcome resistance by synergizing the initial activity of existing cancer therapies. We intend to continue to exploit the potential of these promising compounds with the goal of bringing novel treatments to cancer patients."
The USAN Council (tri-sponsored by the American Medical Association (AMA), the United States Pharmacopeia Convention (USP), and the American Pharmacists Association (APhA), aims for global standardization and unification of drug nomenclature and related rules to ensure that drug information is communicated accurately and unambiguously, working closely with the International Nonproprietary Name (INN) program of the World Health Organization, and various national nomenclature groups.
About Hsp90 Inhibitors
Hsp90 (heat shock protein 90) is a protein chaperone that binds to several sets of signaling proteins, known as "client proteins." These client proteins include a "who's who" list of cancer-relevant targets such as mutated p53, Bcr-Abl, Raf-1, ErbB2 and other kinases, as well as steroid hormone receptors. Disruption of the Hsp90-client protein complexes leads to proteosome-mediated degradation of client proteins. Certain polyketide analogs such as Kosan's lead products in this program, tanespimycin and alvespimycin, bind to Hsp90 and cause its dissociation from, and consequent degradation of, the client proteins, leading to cancer cell death. Because the Hsp90 client proteins are so important in signal transduction and in transcription (processes critical to the growth and survival of cancer cells), tanespimycin and alvespimycin may serve as valuable chemotherapeutic agents in a number of cancers. Moreover, preclinical studies suggest that these compounds are synergistic with certain other inhibitors of the signal transduction client proteins, as well as several conventional anticancer agents. |
