However, combination of the CTLA-4 inhibitor ipilimumab and the PD-1 inhibitor nivolumab carries a higher risk of ICI-related AKI (4.9%) than monotherapy with either ipilimumab (2%), nivolumab (1.9%), or pembrolizumab (1.4%) (28). This evidence concerns the gene PDCD1 and acute kidney injury.