Matching-adjusted indirect comparison of palbociclib versus ribociclib and abemaciclib in hormone receptor-positive/HER2-negative advanced breast cancer.

Palbociclib (PAL), ribociclib (RIB) and abemaciclib (ABM), in combination with fulvestrant (FUL), are approved for the treatment of hormone receptor-positive, HER2-negative advanced breast cancer. This study aims to determine relative efficacy of PAL+FUL versus RIB+FUL and ABM+FUL using matching-adjusted indirect treatment comparisons. Anchored matching-adjusted indirect treatment comparisons were conducted using individual patient data from PALOMA-3 and published summary-level data from MONARCH 2 and MONALEESA-3. The primary outcome was overall survival (OS). OS was similar for PAL+FUL versus ABM+FUL (hazard ratio: 0.87; 95% CI: 0.54-1.40) and RIB+FUL (hazard ratio: 0.89; 95% CI: 0.48-1.63). Adjusting for cross-trial differences suggests similar OS between treatments, underscoring the importance of accounting for these differences when indirectly comparing treatments.