Background: EMBRACA, a randomized 2:1 open-label Phase 3 trial (NCT01945775), showed a significant improvement in progression-free survival with talazoparib vs physician’s choice of chemotherapy (PCT) (HR=0.54; 95%CI: 0.41,0.71; P<.0001) in patients with g BRCA1/2 mut HER2-negative ABC. After accounting for the treatment-emergent period to normalize serious adverse event (SAE)- associated hospitalization and SCM for longer exposure due to increased efficacy, a previous post-hoc analysis (data cutoff 15 Sept 2017) reported a lower SAE-associated hospitalization and SCM utilization ratios for patients treated with talazoparib vs. PCT. This analysis evaluated extended follow-up hospitalization and SCM utilization. Methods: From the extended follow-up safety population (while patients were on talazoparib or PCT) (data cutoff 30 Sept 2019), SAE-associated hospitalization rates (per 100 patient-years), number of patients with ≥1 platelet/red blood cell (RBC) transfusion(s) and 9 types of SCM (opiate, RBC transfusion, platelet transfusion, antiemetic/anti-nauseant, antidiarrheal, appetite stimulant, bone disease treatment, antianemic, immunostimulant) utilization ratios (total duration of each SCM type/treatment-emergent period) were compared between talazoparib vs PCT-treated patients. Results: The safety population consisted of 286 talazoparib and 126 PCT-treated patients. Lower rates of SAE-associated hospitalization were observed with talazoparib vs PCT-treated patients (40.3 vs 71.8 per 100 patient-years). Ten talazoparib-treated patients (3.5%) had ≥1 platelet transfusion(s) vs 0 PCT-treated patients; 112 talazoparib-treated patients (39.2%) had ≥1 RBC transfusion(s) vs 7 (5.6%) PCT-treated patients. Across all types of SCM (except for platelet transfusions), the mean SCM utilization ratios for talazoparib treated patients were lower than PCT-treated patients (table 1). Conclusions: Extended follow-up analyses of patients with g BRCA1/2 mut HER2-negative ABC treated with talazoparib had lower SAE-associated hospitalization rates and lower SCM utilization ratios (except for platelet transfusions) vs PCT. More talazoparib-treated patients had ≥1 platelet/ RBC transfusion(s) vs PCT. These results may support the favorable clinical and patient reported outcomes observed with talazoparib vs PCT-treated patients in EMBRACA.
Mean SCM Utilization Ratio (data cutoff 30 Sept 2019)