Enzalutamide vs. Abiraterone in Chemotherapy-naïve Metastatic Castration-resistant Prostate Cancer (mCRPC)

A Real-World Comparison of Clinical Outcomes in Chemotherapy-naive Metastatic Castration-resistant Prostate Cancer (mCRPC) Patients Who Initiated Enzalutamide vs. Abiraterone Acetate (Abiraterone) in the 100% Medicare Fee-For-Service (FFS) Data (2009-2020)

This study will be a retrospective data analysis to compare outcomes between patients with chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC) who initiated enzalutamide and those who initiated abiraterone using the 100% Fee-For-Service Medicare claims data. The study will address the following objectives:

Primary objective: To compare overall survival (OS) in patients with chemotherapy-naïve mCRPC who initiated enzalutamide vs. abiraterone

Secondary objectives:

• To compare OS in patients with chemotherapy-naïve mCRPC who received only enzalutamide without any subsequent therapy vs. abiraterone without any subsequent therapy
• To compare treatment duration and time to subsequent therapy in chemotherapy-naïve mCRPC patients initiating enzalutamide vs. abiraterone

Inclusion Criteria:

• Male with ≥ 1 diagnosis claim for prostate cancer
• Have documented secondary metastasis code on or after the initial prostate cancer diagnosis
• Have initiated enzalutamide or abiraterone within 90 days prior to the metastasis date or on or after the metastasis date. The initiation date of enzalutamide or abiraterone will be defined as the index date.
• Have evidence of surgical or medical castration before the index date
• At least 18 years old at the index date
• Continuous eligibility for ≥ 12 months prior to the index date

Exclusion Criteria:

• Received chemotherapy, novel hormonal therapy, radium-223, or immunotherapy prior to the index date
• Had a prior history of other cancers