BACKGROUND:In the coBRIM study, cobimetinib plus vemurafenib (C+V) significantly improved survival outcomes vs placebo and vemurafenib (P+V) in patients with advanced/metastatic BRAFV600-mutated melanoma. An analysis of health-related quality of life (HRQOL) from coBRIM is reported. METHODS:Patients completing the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (QLQ-C30) at baseline and ⩾1 time point thereafter constituted the analysis population. Change from baseline ⩾10 points was considered clinically meaningful. RESULTS:Mean baseline scores for all QLQ-C30 domains were similar between arms. Most on-treatment scores for QLQ-C30 domains were also comparable between arms. A transient deterioration in role function in cycle 1 day 15 (C1D15; -14.7 points) in the P+V arm and improvement in insomnia in the C+V arm at C2D15 (-12.4 points) was observed. Among patients who experienced a ⩾10-point change from baseline (responders), between-group differences were greatest for insomnia (16%), social functioning (10%), fatigue (9%) and pain (7%), all favouring C+V. Diarrhoea, photosensitivity reaction, pyrexia, and rash did not meaningfully affect global health status (GHS). Serous retinopathy was associated with a transient decrease in GHS at C1D15 assessment. CONCLUSIONS:In patients with advanced/metastatic BRAFV600-mutated melanoma, treatment with C+V maintained HRQOL compared with P+V, with superior efficacy.