Table 2:

Rates of the more common immune-related adverse events stratified by immune checkpoint inhibitor strategy^*

Immune-related adverse events	Anti–CTLA-4 (ipilimumab)		Anti–PD-1 (nivolumab)		Anti–CTLA4 + Anti–PD1 (ipilimumab + nivolumab)

	Any grade, %	Grade ≥ 3,^† %	Any grade, %	Grade ≥ 3,^† %	Any grade, %	Grade ≥ 3,^† %
All immune-related adverse events	86	27	82	16	96	55

Rash	33	2	26	1	40	5

Colitis	12	9	1	1	12	8

Diarrhea	33	6	20	2	44	10

Hepatitis	4	2	4	1	18	8

Hypothyroidism	4	0	9	0	15	1

Discontinuation owing to immune-related adverse events	15	13	8	5	36	30

Note: CTLA-4 = cytotoxic T-lymphocyte–associated protein 4, irAE = immune-related adverse events, PD-1 = programmed cell death 1.
↵* Results are based on a large phase 3 clinical trial comparing the efficacy and safety of single-agent PD-1, CTLA-4 or the combination in metastatic melanoma.6 Similar immune-related adverse events rates are reproducible in other cancer types.
↵† Grade 3 = severe or medically important but not immediately life-threatening; hospital admission indicated; disabling; limiting self-care, per Common Terminology Criteria for Adverse Events.12