HSP90 KOS-953 is named tanespimycin

Kosan Biosciences Incorporated 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 Council and the World Health Organization.

Tanespimycin is the most advanced Hsp90 inhibitor in clinical trials. The compound is in a Phase Ib trial in combination with Velcade(R) for multiple myeloma, and is in a Phase I trial as a single agent in multiple myeloma. 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.