Cobimetinib combined with vemurafenib was available in France in 2015 through a 'Temporary Authorization for Use' program (TAU, preapproval access pending its marketing on 2016) for patients with v-raf murine sarcoma viral oncogene homolog B1-mutant advanced melanoma. This study aimed to provide real-world outcomes in patients previously registered in this TAU.

This noninterventional, ambispective, multicentre French study, conducted in patients previously registered in TAU, aimed to estimate overall survival (OS) and progression-free survival (PFS) and to describe the tolerability of the therapeutic combination.

At first cobimetinib intake (in combination with vemurafenib), 88% of the 185 evaluable patients had disease stage IV (brain metastasis: 70% of them), 31% had elevated lactate dehydrogenases, and 10% had an Eastern Cooperative Oncology Group (ECOG) index ≥2. Median OS was 16.1 months (95% CI, 12.5-20.7). Brain metastasis (P < 0.001), ECOG index ≥2 (P = 0.007), and hepatic impairment (P = 0.037) were found as independent factors significantly associated with shorter survival. Median PFS was 7.3 months (95% CI, 5.2-8.4). ECOG index ≥2 (P = 0.006) was significantly associated with shorter PFS. Between cobimetinib start and inclusion, increased CPK (3% of patients), retinal serous detachment (3%), decreased left ventricular ejection fraction (3%), increased transaminases (3%), and rash (3%) were the most reported serious adverse events.

This study provides real-world outcomes in France for the vemurafenib-cobimetinib combination available in patients with BRAF-mutant-advanced melanoma. Our data tend to confirm in the real-life setting that this combination therapy is effective in such patients, with a safety profile consistent with previous interventional studies.