Fig. 1: Waterfall plot demonstrating objective response rates for study participants.

The median follow-up time was 12.4 months (95% CI: 2.7–15.4). One patient without a target lesion was excluded from this figure. Prior T-DM1 use (Y yes, N no), hormone receptor (HR) status, number of lines of prior therapy, and assigned dose of ribociclib are notated below the X-axis. PD progressive disease, CR complete response, PR partial response, SD stable disease, Neg negative, Pos positive, Ukn unknown.