Adherence and Persistence on Relugolix for the Treatment of Prostate Cancer in the United States Medicare Fee-for-Service Population.

INTRODUCTION

This real-world study examined persistence and adherence to oral relugolix in Medicare fee-for-service beneficiaries with prostate cancer (PC).

METHODS

In Medicare 100% fee-for-service administrative claims data (2019-2023), eligible patients with PC were identified who had ≥ 2 relugolix claims between December 1, 2020, and September 30, 2023, and 12 months of Parts A, B, and D eligibility before and ≥ 90 days after the first relugolix claim (index date). Persistence (time from first relugolix pharmacy claim to the earliest of either a switch to a different androgen deprivation therapy, discontinuation, death, or end of study period) was assessed up to 36 months after index using a 90-day gap in pharmacy claims to define discontinuation. Adherence, defined as the proportion of patients filling prescriptions to relugolix while persistent on therapy, was assessed every 3 months through month 24 after index using a proportion of days covered ≥ 80% method. Analyses were stratified by PC metastatic status.

RESULTS

Of 5274 patients included, 68% had nonmetastatic PC. Mean (SD) persistence was 11.2 (8.1) months in patients with metastatic PC vs 9.4 (6.9) months in patients with nonmetastatic PC (log-rank test P < .0001). Among patients who persisted on therapy, the adherence rate was 93% through 24 months and was similar between metastatic and nonmetastatic PC cohorts.

CONCLUSIONS

Patients who were persistent on relugolix demonstrated high adherence throughout the study, regardless of metastatic status. These results suggest that relugolix has practical utility in real-world clinical practice.