[2] The most common side effects include diarrhea, rash, nausea (feeling sick), vomiting, pyrexia (fever), photosensitivity (light sensitivity) reaction, abnormal results for certain liver function tests (increased levels of alanine aminotransferase, aspartate aminotransferase) and abnormal results for an enzyme related to muscle breakdown (creatine phosphokinase).

[9][10][11] In the United States, cobimetinib is indicated for the treatment of adults with unresectable or metastatic melanoma with a BRAF V600E or V600K mutation, in combination with vemurafenib.

[2] In the European Union, cobimetinib is indicated for use in combination with vemurafenib for the treatment of adults with unresectable or metastatic melanoma with a BRAF V600 mutation.

[5] Common adverse effects observed in cobimetinib and vemurafenib co-treated persons in clinical trials included diarrhea, nausea, vomiting, rash, photosensitivity, and pyrexia.

[15][12] The US Food and Drug Administration (FDA) approved cobimetinib based on evidence from one clinical trial of 495 participants with melanoma containing the BRAF V600 mutation that was advanced or could not be removed by surgery.