PDCD1 and myocarditis: There are discrepancies in literature about this as one study in 2018 found anti-CTLA-4 to induce more myocarditis whereas a meta-analysis in 2021 again found more myocarditis cases due to anti-PD-1 (69.4%) than CTLA-4 (20%) (Mahmood et al., 2018; Rubio-Infante et al., 2021).