A combination drug therapy developed by researcher at the UCLA Jonsson Comprehensive Cancer Center has been approved by the U.S. Food and Drug Administration to treat metastatic melanoma to help people with an advanced form of the disease, and it does not cause a secondary skin cancer, a side effect seen in some patients who took only one of the drugs.
The study was conducted at UCLA and 135 other sites in the U.S., Europe, Australia and Russia and the drugs vemurafenib (marketed under the brand name Zelboraf) and cobimetinib (Cotellic), were tested in combination on approximately 495 patients who had BRAF V600, a mutation-positive advanced melanoma.
Since they showed significantly better responses than those who had been prescribed vemurafenib alone, the study was continued and the FDA granted the therapy “priority review” status, leading to its approval on November 10, 2015.
“Today’s approval is a very significant advance in the treatment of metastatic melanoma,” said Dr. Antoni Ribas, the lead researcher at the Jonsson Cancer Center. “For patients with a BRAF mutated melanoma, the combination has higher activity to shrink their tumors, and with less side effects than the drugs on their own.”
An estimated 70,000 people in the U.S. are diagnosed with melanoma annually in the U.S., and 8,000 people die of the disease each year. About half of the patients with metastatic melanoma have a mutated protein called a BRAF mutation.
This mutation can be treated with vemurafenib, which was recently approved by the FDA. Researchers previously discovered that the BRAF mutation gives melanoma the signal to grow continuously as a cancer, but vemurafenib taken by itself cannot completely block that signal.
The new study showed that when the experimental drug cobimetinib is added, the combination slows the growth of the melanoma, Ribas said.
Past research had found that 25 percent of patients who had been given vemurafenib alone developed a secondary skin cancer but combining cobimetinib with vemurafenib decreased the incidence of secondary skin cancer.
“When melanoma is diagnosed early, it is generally a curable disease, but most people with advanced melanoma have a poor prognosis,” Dorshkind said. The study was led by UCLA’s Dr. Roger Lo, a Jonsson Cancer Center member and associate professor of medicine.