Dermal events (23.8%), colitis (5.6%), hepatitis (4.3%), hypophysitis (0.4%), myasthenic (0.3%), and myocarditis (0.3%) were more common with CTLA-4 inhibitors, whereas pneumonitis (3.7%), thyroid events (14.3%), pancreatic events (1.0%), and rheumatic events (0.2%) were more common with PD-1/PD- L1 inhibitors. Here, CTLA4 is linked to hepatitis A virus infection.