Limitations
These analyses are limited by their exploratory post hoc nature, which did not allow for detecting statistical significance in the subgroups. Except for 2 preplanned subgroups (RAM and no RAM), all others were analyzed post hoc. Our interpretation of the data and comparison between subgroups was limited by the substantial overlap between the subgroups. Prior treatments varied from one country to another owing to regional differences in recommended treatment schedules, drug registrations, etc. Also, because few patients in the TAGS trial had previously received PD-1/PD-L1 therapy, the impact of prior immunotherapy on FTD/TPI outcomes is unclear and will need to be examined in future studies.