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

N/ACompletedNCT05520138

Pfizer5,506 enrolled

Overview

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

Study Type

OBSERVATIONAL

Enrollment

5,506

Conditions

Prostatic Neoplasms, Castration-Resistant

Interventions

EnzalutamideDRUG

As provided in real-world setting

Eligibility

Sex: MALEMin age: 18 Years

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

Overall Survival (OS): Inverse Probability Treatment Weighting (IPTW)

OS (time to death) was defined as the time from the initiation of enzalutamide or abiraterone (i.e., index date) to the date of death. Participants who did not die were censored at their last available follow-up, which was defined as the earlier of disenrollment from Medicare or end of data availability. Kaplan-Meier method was used for analysis.

Time frame: From index date to date of death or censoring date, whichever occurred first (from 10-Sep-2014 to 31-Dec-2020, approximately 76 months); retrospective data extracted and evaluated from study start date and until study completion (approximately 10 months)

Secondary Outcomes

OS Among Participants Without Any Subsequent Therapy: IPTW

Treatment Duration: IPTW

Treatment duration of the index treatment was defined as the time from the initiation of enzalutamide or abiraterone (i.e., index date) to the discontinuation date. Discontinuation was defined as the earliest of 1) death, 2) last observed administration plus day of supply associated with last administration, or 3) day before the start of next line of therapy. Death, a gap of 90 days or more after the last observed prescription date + day of supply, and initiation of next line of therapy was considered as discontinuation events. Participants who did not discontinue were censored at their last available follow-up, which was defined as the earlier of disenrollment from Medicare or end of data availability.

Time frame: From index date to date of discontinuation event or censoring date, whichever occurred first(from 10-Sep-2014 to 31-Dec-2020, approximately 76months); retrospective data extracted and evaluated from start date and until completion(approximately 10months)

Time to Subsequent Therapy: IPTW

Time to subsequent therapy was defined as the time from the initiation of enzalutamide or abiraterone (i.e., index date) to the start of next line of therapy. Participants who did not start a new line of therapy were censored at their last available follow-up, which was defined as the earliest of 1) death, 2) disenrollment from Medicare, and 3) end of data availability.

Time frame: From index date to start of next line of therapy (from 10-Sep-2014 to 31-Dec-2020, approximately 76 months); retrospective data extracted and evaluated from study start date and until study completion (approximately 10 months)