Table 2. Variables significantly associated with response to anti-PD-1 on univariate analysis.

Source	Objective response rate (ORR),a %	Odds ratio (OR) (95% CI)	P value
Total cohort	44.3	NA	NA
Age <65 years	34.9	0.42 (0.24, 0.72)	<0.001
Elevated LDHb	29.5	0.38 (0.21, 0.69)	<0.001
Female sex	33.8	0.50 (0.29, 0.89)	0.01
Previous ipilimumab treatment	35.4	0.35 (0.20, 0.62)	<0.001
Liver metastasis	26.5	0.34 (0.17, 0.62)	<0.001

Abbreviations: CI=confidence interval; LDH=lactate dehydrogenase; NA=not applicable.

^aORR was defined as the percentage of patients with a complete or partial response.

^bDefined as LDH ratio >1.