The U.S. Food and Drug Administration (FDA) has approved Cotellic (cobimetinib, Genentech) to be used in combination with vemurafenib for the treatment of advanced melanoma that has a BRAF V600E or V600K gene mutation and has spread to other parts of the body or cannot be removed by surgery. Cotellic blocks the activity of MEK—an enzyme that is part of a larger signaling pathway—to prevent or slow cancer cell growth while BRAF inhibitor vemurafenib (Zelboraf, Genentech) affects a different part of the same pathway. The presence of a BRAF V600E or V600K mutation in patients’ tumor specimens must be confirmed prior to starting treatment with Cotellic in combination with vemurafenib.
In a randomized clinical study of 495 patients with previously untreated BRAF V600 mutation-positive melanoma (that was advanced or not removable via surgery), participants received vemurafenib and were randomly selected to also take either Cotellic or placebo. On average, patients taking Cotellic plus vemurafenib experienced a delay in the amount of time it took for their disease to worsen: approximately 12.3 months post-treatment compared to approximately 7.2 months post-treatment for those taking vemurafenib only. Additionally, patients taking Cotellic plus vemurafenib lived longer compared to those taking vemurafenib only (approximately 65% vs. 50% were living 17 months after starting treatment), and 70% of those taking Cotellic plus vemurafenib experienced complete or partial shrinkage of their tumors vs. 50% among those taking vemurafenib plus placebo.
The most common side effects of treatment with Cotellic in combination with vemurafenib are diarrhea, photosensitivity, nausea, fever and vomiting.
“As we continue to advance our knowledge of tumor biology, we have learned that cancer cells have a remarkable ability to adapt and become resistant to targeted therapies. Combining two or more treatments addressing different cancer-causing targets may help to address this challenge,” said Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Today’s approval provides a new targeted treatment that, when added to vemurafenib, demonstrates greater benefit than vemurafenib alone in patients with BRAF mutation-positive melanoma.”