Statistical analyses
tumor
TUMOR
The study had a two‐stage design. During Stage 1, approximately 25 patients per arm were planned to provide a preliminary assessment of DCR and safety. The DCR of abemaciclib (Arm A) and abemaciclib plus LY3023414 (Arm B) were compared to SOC chemotherapy (Arm D). The null hypothesis assumed the DCR with SOC or abemaciclib treatment to be 50%. The probability of stopping at the end of Stage 1 was 11% if the DCR with abemaciclib treatment was 65% (i.e., DCR difference of abemaciclib vs. SOC was +15%). Conversely, the probability of stopping at the end of Stage 1 was 72% if the DCR with abemaciclib was 40% (i.e., DCR Difference of abemaciclib vs. SOC was −10%). At the end of Stage 1, an additional 50 patients were planned to enroll in each treatment arm with a DCR at least as good as SOC (i.e., DCR difference of abemaciclib vs. SOC ≥0), totaling approximately 75 patients in each arm. All efficacy analyses were performed on the intent‐to‐treat (ITT) population (all randomized patients). Stage 1 analysis was performed approximately 16 weeks after the last patient entered treatment.All tumor assessments were used to determine DCR and ORR. Each of these rates, point estimates, and confidence intervals (CIs) (using the normal approximation to the binomial) were calculated by the treatment arm. Kaplan–Meier (KM) method was used to estimate the PFS and OS for each treatment arm.The safety population included all patients who received any study treatment. Safety data were summarized by treatment arms. The PK population included patients who had ≥1 evaluable PK sample.