WASHINGTON -- The FDA has approved vemurafenib (Zelboraf) for the treatment of metastatic and unresectable melanoma along with a companion genetic mutation test.
Vemurafenib is specifically indicated for patients whose tumors express a BRAF V600E mutation, the FDA said in a statement. The companion diagnostic tool, known as the cobas 4800 BRAF V600 Mutation Test, can help determine if the melanoma cells contain the indicated mutation.
Vemurafenib is a BRAF inhibitor that blocks the function of the V600E-mutated BRAF protein. The drug has not been studied in patients who test negative for the BRAF V600E mutation, the FDA stated.
Vemurafenib is the second drug approved for late-stage melanoma this year; ipilimumab (Yervoy) was approved by the FDA in March.
The safety and efficacy of vemurafenib were determined in a trial of 675 patients with late-stage melanoma who had the BRAF V600E mutation. They had not received prior therapy. Patients were assigned to vemurafenib or dacarbazine. The endpoint was overall survival.
The median survival for vemurafenib has not yet been reached, with 77% of patients still alive versus a median survival of eight months in the dacarbazine group, with 64% of patients still alive, the statement said.
Adverse events in the trial included joint pain, rash, hair loss, fatigue, nausea, and skin sensitivity to sunlight. Additionally, roughly 26% of patients developed cutaneous squamous cell carcinoma, which was managed with surgery.
Approval for the companion mutation test was based on data from the same safety and efficacy trial. Samples from melanoma tissue were collected to test for the BRAF V600E mutation.
Vemurafenib received FDA priority review, which is given to drugs that may offer major advances in therapy, or treatment where inadequate treatment is available.
Monthly costs for vemurafenib treatment will be $9,400. The total cost will be $56,400 for the estimated six months of treatment time, a representative from drugmaker Genentech said. The genetic mutation test will cost from $120 to $150.