CTLA4 and Diarrhea: Diarrhea is one of the most common irAEs, affecting approximately 44% (vs. 10% for grade 3-4) of patients treated with a combination of CTLA-4 and PD-(L)1 inhibitors, 36% (vs. 8% for grade 3-4) of patients treated with anti-CTLA-4, and 11% (vs. 1% for grade 3-4) of patients treated with anti-PD-(L)1 (34).