Table 2.

Clinical benefits from adding cetuximab to a PD-1 inhibitor therapy according to p16 status

Comparison	ORR				1-year OS rate *
	Rate (%)	OR (95% CI)	P effect	P homogeneity	Rate (%)	Ratio of rate (95% CI)	P effect
Cetuximab plus anti-PD-1 versus anti-PD-1 in p16-positive patients	18 versus 17	1.19 (0.51 to 2.74)	0.686	0.695	55 versus 40	1.37 (0.80 to 2.36)	0.252
Cetuximab plus anti-PD-1 versus anti-PD-1 in p16-negative patients	46 versus 15	5.45 (2.79 to 10.64)	<0.001	0.389	59 versus 36	1.62 (1.26 to 2.07)	<0.001
p16-positive versus p16-negative patients after cetuximab plus anti-PD-1 therapy	18 versus 46	0.29 (0.13 to 0.68)	0.004	0.818	55 versus 59	0.95 (0.55 to 1.62)	0.850

*Due to the lack of data, tests for heterogeneity could not be conducted.

OR, odds ratio; ORR, Objective response rate; OS, overall survival; PD-1, programmed cell death protein 1.