Zelboraf Approved for Late-Stage Melanoma

Aug. 17, 2011 -- The FDA today approved Zelboraf, a drug that can extend survival for the 50% of melanoma patients whose tumors carry the BRAF V600E mutation.

Zelboraf is approved for inoperable or late-stage melanoma that tests positive for the BRAF mutation. In concert with the drug approval, the FDA also approved a new test for the BRAF mutation.

Zelboraf does not cure melanoma, which this year will kill some 9,000 Americans. But Zelboraf will make a big difference in the lives of BRAF-positive melanoma patients, says Anna Pavlick, DO, co-director of the melanoma program at New York University's Cancer Institute. Pavlick was one of the investigators in Zelboraf clinical trials.

"We now have the capacity to analyze a patient's melanoma tumor for the genetic mutation BRAF and use the targeted treatment Zelboraf to attack the tumor, shrink it, and stop the progression of this deadly disease," Pavlick says in an NYU news release. "The drug comes in a simple pill form, taken twice a day, and has been well tolerated by patients."

Nevertheless, Zelboraf has some serious side effects. Some 26% of patients in clinical trials developed a nonmelanoma form of skin cancer called cutaneous squamous cell carcinoma, which can usually be removed via relatively simple surgery.

Other side effects include joint pain, rash, hair loss, fatigue, nausea, and skin sensitivity to sunlight. Patients taking Zelboraf must avoid sun exposure.

Zelboraf Increases Melanoma Survival

An international phase III clinical trial of Zelboraf in 675 BRAF-positive patients was stopped early when it became clear that the drug was clearly reducing deaths. All patients assigned to traditional chemotherapy were offered the new drug.

It's not yet clear how long Zelboraf can increase melanoma survival. In the phase III study, progression-free survival -- the time since treatment when disease gets worse -- was 5.3 months for patients on Zelboraf vs. 1.6 months for patients on standard chemotherapy.

"For patients with metastatic melanoma with the BRAF V600E mutation, the availability of [Zelboraf] is a major defining moment that will have an important effect on survival and quality of life," Dartmouth Medical School researcher Marc S. Ernstoff, MD, writes in a June 30 editorial in the New England Journal of Medicine.

It's been a hopeful year for melanoma patients and their families. Last March, the FDA approved Yervoy for late-stage melanoma.

Zelboraf, originally dubbed PLX4032 and given the generic name vemurafenib, was initially developed by Plexxikon Inc., a member of the Daiichi Sankyo Group of pharmaceutical companies. The drug is being co-marketed by Genentech, a division of Roche. Roche Molecular Systems makes the newly approved BRAF test.