Safety
neutropenia, fatigue, toxicity, thrombocytopenia, TEAEs
ADVERSE EVENTS, THROMBOCYTOPENIA, NEUTROPENIA
Treatment‐emergent adverse events (TEAEs) occurred in >99% of the treated patients (Treatment‐emergent adverse events occurring in ≥15% of patients (Safety Population).Abbreviations: Grade 4 neutropenia in 1 (14.3%) patient.Grade 4 thrombocytopenia in 1 (3.1%) patient.Grade 4 thrombocytopenia in 3 (9.1%) patients.Grade 4 thrombocytopenia and neutropenia in 2 patients each [7.7%], respectively.In Stage 1, 84.4%, 75.8%, and 88.5% of patients treated with abemaciclib, abemaciclib plus LY3023414, and SOC, respectively, experienced at least 1 Grade ≥3 TEAE, mostly hematologic toxicity and fatigue (Table Serious AEs regardless of causality were observed in 55.1% of patients. Two patients (28.6%) in the safety lead‐in, 4 (12.5%) in Arm A, 11 (33.3%) in Arm B, and 7 (26.9%) in Arm D experienced SAEs related to treatment. Nine patients (9.2%) died due to AEs while on treatment (