Subjects: R and D
Plexxikon announced last week that its experimental drug shrank melanoma tumors in a whopping 81% of the patients who received it.
Scientists suggested that the positive results from this early-stage trial might represent a breakthrough in the treatment of a notoriously recalcitrant malignancy, even though the drug’s beneficial results were not permanent. The cancers began growing again in every patient but two after the course of treatment ended.
“Metastatic melanoma is a challenging disease to treat. There have been no significant therapeutic advances in the past 20 years,” Paul Chapman, senior author of the study told BurrillReport.
“We learned that half of melanomas are addicted to a mutated gene called BRAF; this new drug inhibits BRAF and shuts off these tumors,” added Chapman, who is an attending physician at the Melanoma and Sarcoma Service at Memorial Sloan-Kettering.
The BRAF mutation occurs in 40-60% of people with melanoma.
Berkeley-based Plexxikon’s experimental drug is called PLX4032. It appeared to shrink metastatic lesions in multiple locations including liver, bone and the small bowel.
Plexxikon has co-developed the drug with Roche under a license and collaboration agreement. Roche also plans to market a gene-based diagnostic tool that can identify melanoma patients who carry the genetic peculiarity that renders their cancers receptive to PLX4032.
Plexxikon has begun mid- and late-stage studies of its drug simultaneously in an effort to find out as quickly as possible whether it can improve survival in patients with melanoma.