New Melanoma Drug Nearly Doubles Survival

A new melanoma drug nearly doubled survival time for metastatic melanoma in more than half of the patients who participated in a Phase 2 clinical trial. The drug, vemurafenib, known commercially as Zelboraf, was approved last year to treat melanoma. It targets a genetic variant of melanoma carrying the V600 mutation in a gene called BRAF. About half of melanoma patients have this form of the cancer.

The trial found that out of 132 patients enrolled in the trial, 47 percent had a partial response to the drug and six percent exhibited a complete response, for a total response rate of 53 percent. Overall survival was nearly 16 months – far longer than the typical survival of just six to 10 months for most patients whose melanoma has metastasized beyond the initial tumor site.

Results from the trial, led by co-principal investigators Jeffrey Sosman, M.D., director of the Melanoma Program and co-leader of the Signal Transduction Program at VICC, and Antoni Ribas, M.D., professor of Hematology/Oncology at UCLA’s Jonsson Comprehensive Cancer Center, were published in the Feb. 23 issue of the New England Journal of Medicine.

“This study confirms what we have discovered in our earlier trials." said Sosman. "Many of our patients are exhibiting a strong, immediate response to this drug and some are living significantly longer, with manageable side effects.” He added, “It was interesting to note that a few of the patients were treated with the drug for up to six months before showing convincing evidence of response.”

“This study shows that Zelboraf changes the natural history of the disease,” said Ribas. “These results tell us that this drug is having a very big impact, and this changes the way we treat metastatic melanoma.”

While these results are cause of optimism, most melanoma patients treated with vemurafenib eventually see their tumor develop resistance to the drug. GeneKey has analyzed such resistant tumors and discovered potential mechanisms and drugs that might help overcome resistance. Further investigation is currently under way.