Amid growing excitement for immune checkpoint inhibitors of programmed death protein 1 (anti-PD1 agents), little is known about whether race- or sex-based disparities exist in their use. In this observational study, we constructed a large and mostly community-based cohort of patients with advanced stage cancers, including melanoma, non-small cell lung cancer (NSCLC), and renal cell carcinoma, to compare the odds of receiving systemic treatment with or without anti-PD1 agents by race and by sex. In multivariable models that adjusted for age, stage, and number of prior anticancer therapies, we found no significant race-based disparities in anti-PD1 treatment. However, among patients with NSCLC, males had significantly higher odds of receiving anti-PD1 treatment compared with females (odds ratio 1.13, 95% confidence interval 1.02–1.24, p =.02). This finding suggests that as anti-PD1 agents enter the market to transform patient care, it will be critical to monitor for disparities in the use of these drugs.