Immune checkpoint inhibitors for metastatic uveal melanoma: a meta-analysis

Several studies have evaluated immune checkpoint inhibitors (ICIs) for metastatic uveal melanoma; however, the efficacy of ICIs in the previous studies varied greatly. In this systematic review, we searched for prospective or retrospective studies on single or dual-ICIs for metastatic uveal melanoma treatment. A random-effect model meta-analysis with generic inverse-variance was conducted, and 36 articles representing 41 cohorts of 1414 patients with metastatic uveal melanoma were included. The pooled outcomes were as follows: objective response rate (ORR) was 5.6% (95% confidence interval [95%CI] 3.7-7.5%; I², 36%), disease control rate (DCR) was 32.5% (95% CI 27.2-37.7%; I², 73%), median progression-free survival was 2.8 months (95% CI 2.7-2.9 months; I², 26%), and median overall survival (OS) was 11.2 months (95% CI 9.6-13.2 months; I², 74%). Compared to single-agent ICI, dual ICI led to better ORR (single-agent: 3.4% [95% CI 1.8-5.1]; dual-agent: 12.4% [95% CI 8.0-16.9]; P < 0.001), DCR (single-agent: 29.3%, [95% CI 23.4-35.2]; dual-agent: 44.3% [95% CI 31.7-56.8]; P = 0.03), and OS (single-agent: 9.8 months [95% CI 8.0-12.2]; dual-agent: 16.3 months [95% CI 13.5-19.7]; P < 0.001). Our analysis provided treatment outcomes as described above. Dual-ICIs appear better than single-agent ICIs for the treatment of metastatic uveal melanoma.