Study of persistence and adherence to ADT in prostate cancer: relugolix, degarelix, and GnRH agonists in the US.

AIMS: Androgen deprivation therapy (ADT) is standard for advanced prostate cancer. Relugolix, a gonadotropin-releasing hormone (GnRH) receptor antagonist, is the only oral ADT, with limited real-world data on therapy persistence and adherence. This retrospective study evaluates persistence and adherence of relugolix, degarelix, and GnRH agonists (leuprolide, goserelin, triptorelin, histrelin) using data from the IBM MarketScan Research Database (Jan 2017 - Dec 2022).

METHODS

The IBM MarketScan Research Database (1 January 2017 - 31 December 2022) was used for enrollment history and claims. ADT adherence was measured by the proportion of days covered (PDC) at 3, 6, and 12 months, calculated as days on ADT divided by period duration. Kaplan-Meier analysis assessed treatment persistence by measuring time to treatment discontinuation.

RESULTS

Relugolix had higher adherence (PDC ≥ 80%) at 12 months (60.8%) compared to degarelix (13.0%) and GnRH agonists (46.3%). Median time to discontinuation was also longer for relugolix (13.5 months) than degarelix (3.1 months) and GnRH agonists (8.8 months). Persistence and adherence rates were higher in metastatic prostate cancer.

CONCLUSIONS

Findings support relugolix use as an oral treatment due to its favorable persistence and long-term adherence profiles.