Table 2.

Survival outcome data (OS and PFS) correlated with ctDNA clearance, and subgroup analysis based on disease site, treatment type, line of treatment, level of ctDNA change and timing of second ctDNA sampling

Subgroups/outcome	HR (OS)	95% CI	Subgroup difference p	HR (PFS)	95% CI	Subgroup difference p
All patients	0.18	0.12 to 0.26	NA	0.23	0.17 to 0.31	NA
Disease site
Melanoma	0.20	0.12 to 0.33	0.27	0.12	0.06 to 0.25	0.15
Lung	0.16	0.08 to 0.31		0.23	0.14 to 0.37
Others	0.05	0.01 to 0.26		0.34	0.20 to 0.58
Treatment
Single agent	0.14	0.07 to 0.31	0.45	0.23	0.16 to 0.33	0.004
Multi-agent	0.20	0.12 to 0.32		0.23	0.13 to 0.41
Treatment line
First line	0.22	0.13 to 0.36	0.31	0.19	0.11 to 0.34	0.002
Later line	0.14	0.07 to 0.28		0.29	0.19 to 0.42
Level of ctDNA change
≥50% reduction	0.17	0.05 to 0.62	0.93	0.29	0.12 to 0.71	0.21
Undetectable levels	0.18	0.12 to 0.27		0.22	0.15 to 0.31
Interval of second ctDNA sampling
10–16 weeks	0.22	0.13 to 38		0.18	0.10 to 0.32	0.004
<10 weeks	0.13	0.06 to 26		0.25	0.17 to 0.36

OS, overall survival; PFS, progression-free survival.