Treatment Duration, Healthcare Resource Utilization, and Costs Among Chemotherapy-Naive Patients with Metastatic Castration-Resistant Prostate Cancer Treated with Enzalutamide or Abiraterone Acetate: A Retrospective Claims Analysis
Advances in Therapy. 2018 Oct;35(10):1639-1655
Enzalutamide and abiraterone acetate (plus prednisone) are new hormonal treatments for metastatic castration-resistantprostate cancer (mCRPC). This study compared treatment duration, healthcare resource utilization (HRU), and treatment costs for chemotherapy-naïve mCRPC patients treated with enzalutamide or abiraterone acetate in the USA.
Chemotherapy-naïve mCRPC patients initiating treatment with enzalutamide or abiraterone acetate were identified from administrative claims. Continuous enrollment ≥ 6 months before and ≥ 3 months after the index date (initiation date of enzalutamide or abiraterone acetate) was required. Treatment duration, all-cause and prostate cancer-related HRU, and costs were estimated during the post-index period. Multivariable analyses compared HRU and costs between cohorts, adjusting for baseline characteristics.
Overall, 920 chemotherapy-naïve patients initiated enzalutamide and 2310 initiated abiraterone acetate (median follow-up, 10.7 and 13.5 months, respectively). More enzalutamide-treated patients had corticosteroid-sensitive comorbidities at baseline. Treatment durationwas longer with enzalutamide versus abiraterone acetate (median, 10.7 vs. 8.8 months; P = 0.008). Enzalutamide was associated with fewer all-cause inpatient admissions [adjusted incidence rate ratio (95% confidence interval) 0.87 (0.76, 0.99)], days of hospitalization [0.84 (0.70, 1.02)], and outpatient visits [0.94 (0.90, 0.98)], and fewer prostate cancer-related outpatient visits [0.92 (0.87, 0.96)] compared with abiraterone acetate. Enzalutamide was also associated with lower prostate cancer-related inpatient and emergency department costs[adjusted differences, $122 (P = 0.024) and $28 (P = 0.009), respectively].
Chemotherapy-naïve mCRPC patients treated with enzalutamide versus abiraterone acetate had longer treatment durationand incurred lower HRU and prostate cancer-related inpatient and emergency department costs.