Results
One hundred and six patients were enrolled. Abemaciclib plus galunisertib did not advance to Stage 1 for reasons unrelated to safety or efficacy. Stage 1 DCR was 15.2% with abemaciclib monotherapy, 12.1% with abemaciclib plus LY3023414, and 36.4% with SOC. Median PFS was 1.7 months (95% CI: 1.4–1.8), 1.8 months (95% CI: 1.3–1.9), and 3.3 months (95% CI: 1.1–5.7), respectively. No arms advanced to Stage 2. No new safety signals were identified.