Association between sex and efficacy of immune checkpoint inhibitors: a systematic review and meta-analysis.

Aim: To explore the association between sex and immune checkpoint inhibitors (ICIs). Materials & methods: We assessed the difference in survival outcomes from ICIs between sexes using an interaction test. Results: 108 studies representing 70,243 patients were included. In the first-line setting, the pooled interaction HR was 0.97 (95% CI: 0.91-1.04). In the subsequent-line setting, the pooled interaction HR was 0.85 (95% CI: 0.77-0.95). When ICIs were given as perioperative therapy or as systemic therapy in patients with positive PD-L1 expression, both men and women obtained equal survival benefits. Conclusion: Both sex, line of therapy, cancer (sub)type and PD-L1 status should be taken into account in the assessment of risk versus benefit when deciding to offer ICIs to patients.