Melanoma drug breaks new ground

New York

- Scientists are heralding Plexxikon’s experimental melanoma drug as a “breakthrough” after it successfully shrank patients’ tumors in a clinical trial, according to onemedplace.com.

Researchers at Sloan-Kettering Memorial Cancer Center, New York, found that the drug, PLX4032, caused tumors to shrink in 70 percent of patients with a specific genetic mutation. The tumors of two of the 27 patients who participated in the study disappeared completely. The drug offers a vast improvement over chemotherapy, which only shrinks tumors in 13 percent to 15 percent of melanoma patients, according to researchers.

PLX4032 works by blocking the activity of a cancer-causing gene mutation involved in 50 percent to 60 percent of melanomas. Approximately 40 percent of patients without the gene mutation did not respond to the drug, according to onemedplace.com.

Sloan-Kettering researchers expect to start a larger phase 2 trial at the end of the year, and an international phase 3 trial is planned for late 2009 or early 2010. It is expected to involve several hundred patients.

Plexxikon is developing PLX4032 in conjunction with Roche.