Table 2.

Summary of OS hazard ratios in subgroup analysis comparing overall survival in patients who received dual immunotherapy vs chemotherapy.

Overall survival
Group	No. of studies	No of patients	HR (95% CI)	p	Interaction, p	I 2 (%)
Sex
Male	3	1,478	0.68 (0.61, 0.77)	<0.00001	<0.00001	0%
Female	3	649	0.80 (0.67, 0.97)	0.02		0%
Age
<65 years	3	1,117	0.69 (0.60, 0.79)	<0.00001	<0.00001	0%
65–75 years	3	877	0.72 (0.62, 0.84	<0.0001		0%
≥75 years	2	183	0.96 (0.69, 1.34)	0.81		1%
ECOG PS
0	2	620	0.59 (0.42, 0.84)	0.003	<0.00001	57%
1	2	1,255	0.76 (0.67, 0.86)	<0.0001		0%
Smoking status
Never-smoker	3	311	1.00 (0.76, 1.31)	0.99	<0.00001	0%
Smoker	3	1,853	0.69 (0.62, 0.77)	<0.00001		0%
Histology type
Squamous	3	625	0.64 (0.54, 0.77)	<0.00001	<0.00001	0%
Non-squamous	3	1,552	0.75 (0.66, 0.84)	<0.00001		0%
Liver metastasis
Yes	2	406	0.82 (0.66, 1.02)	0.08	<0.00001	0%
No	2	1,479	0.69 (0.61, 0.78)	<0.00001		0%
Bone metastasis
Yes	2	523	0.70 (0.57, 0.85)	0.0003	<0.00001	0%
No	2	1,362	0.72 (0.63, 0.81)	<0.00001		0%
CNS metastasis
Yes	2	237	0.51 (0.29, 0.89)	0.02	0.0001	70%
No	2	1,648	0.74 (0.66, 0.83)	<0.00001		0%
IO drug
Anti-PD-1	2	1,885	0.73 (0.66, 0.81)	<0.00001	0.0004	0%
Anti-PD-L1	4	2,673	0.87 (0.76, 0.99)	0.03		50%

ECOG PS, Eastern Cooperative Oncology Group performance status; IO, immuno-oncology; CNS, central nervous system.