Kosan Biosciences Incorporated has initiated a phase I clinical trial evaluating KOS-1584 (9,10-didehydroepothilone D), a second-generation epothilone. KOS-1584 will be initially tested in patients with advanced malignancies.

The first trial is a phase I dose-escalating study designed to establish the maximum tolerated dose, pharmacokinetics, pharmacodynamics, safety, and potential clinical benefit of the drug when administered as an intravenous infusion every three weeks. The first site has been initiated under the direction of Principal Investigator Dr. Miguel Villalona, of the Ohio State University Arthur James Cancer Centre, the company said here.

"KOS-1584 expands the Kosan and Roche collaboration by providing a complementary drug candidate to our first generation epothilone, KOS-862 which continues in a phase II monotherapy trial in breast cancer and multiple phase Ib studies," said Daniel V. Santi, chairman and CEO at Kosan Biosciences.

KOS-1584 is a polyketide that inhibits cancer cell growth in vitro by a mechanism similar to paclitaxel. Preclinical models have demonstrated Anti-tumour efficacy against paclitaxel-resistant tumours. Under a global development and commercialization agreement between Kosan and Roche, Roche has the worldwide exclusive right to market and sell KOS-862 and epothilone analogs owned by or licensed to Kosan for the treatment of cancer; Kosan will co-develop and has the right to co-promote Kosan/Roche epothilone products in the US for the treatment of cancer.