Real-world outcomes in patients with melanoma brain metastasis: a US multisite retrospective chart review study of systemic treatments.

Objective: This study examined real-world treatment patterns and outcomes in patients with melanoma brain metastasis (MBM) treated with first-line immunotherapy consisting of nivolumab plus ipilimumab or anti-programmed death-1 (PD-1) monotherapy (nivolumab or pembrolizumab) or targeted therapy consisting of BRAF/MEK inhibitors.

Design: Retrospective chart review study.

Setting: Academic medical centres, community hospitals and private practice offices.

Participants: Included patients diagnosed with melanoma with brain metastasis in the USA.

Outcome measures: The statistical analysis was descriptive in nature. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method and compared between treatments in a univariate Cox proportional hazards model.

Results: In total, 472 patients with MBM who received first-line nivolumab plus ipilimumab (n=246), anti-PD-1 monotherapy (n=112) or BRAF/MEK inhibitors (n=114) were identified. Patients receiving nivolumab plus ipilimumab, compared with patients receiving anti-PD-1 monotherapy or BRAF/MEK inhibitors, had favourable baseline prognostic factors, such as younger age, fewer or smaller brain metastases, better Eastern Cooperative Oncology Group performance status and less frequently elevated lactate dehydrogenase. Median follow-up times were 15.4 months (range 0.1 to 37.0), 13.3 months (range 0.3 to 36.6) and 13.9 months (range 1.9 to 36.5), respectively. Numerically longer OS was observed with nivolumab plus ipilimumab versus anti-PD-1 monotherapy (HR 0.47, 95% CI 0.34 to 0.67) or BRAF/MEK inhibitors (HR 0.72, 95% CI 0.50 to 1.04) and numerically longer PFS was observed with nivolumab plus ipilimumab versus anti-PD-1 monotherapy (HR 0.74, 95% CI 0.53 to 1.02) or BRAF/MEK inhibitors (HR 0.82, 95% CI 0.60 to 1.12). With nivolumab plus ipilimumab, anti-PD-1 monotherapy and BRAF/MEK inhibitors, 1-year OS rates were 79%, 60% and 72%, respectively; 1-year PFS rates were 68%, 58% and 59%.

Conclusions: In this real-world study, first-line nivolumab plus ipilimumab appeared to provide benefit versus anti-PD-1 monotherapy and BRAF/MEK inhibitors in patients with MBM, consistent with pivotal trial data. However, the observed benefit may have been due to confounding and selection bias, given that patients receiving nivolumab plus ipilimumab had favourable baseline prognostic factors compared with patients receiving anti-PD-1 monotherapy or BRAF/MEK inhibitors.