Evaluation of persistence and adherence for oral and injectable androgen deprivation therapies (ADT) in United States (US) patients with prostate cancer (PC).

e17110 Background: Relugolix (REL) is the only oral gonadotropin-releasing hormone (GnRH) antagonist available for patients (pts) with advanced PC. Other ADT options for these pts include the injectable GnRH antagonist degarelix (DEG) or injections or implants of GnRH agonists (i.e., leuprolide, goserelin, triptorelin, or histrelin). This study assessed persistence and adherence for REL, DEG, and GnRH agonists in US pts with PC. Methods: This retrospective study used the Merative MarketScan Research Claims Database (Commercial Claims and Medicare Supplemental; 01/2017–12/2022). Eligible pts were adult men with ≥1 claim with PC diagnosis who initiated REL, DEG, or a GnRH agonist (first claim was the index date) between 01/01/2021 and 06/30/2022. Pts were classified into these 3 mutually exclusive cohorts based on the index ADT. Kaplan–Meier (KM) analysis was used to assess persistence (i.e., time from index to treatment discontinuation defined as a gap in treatment of ≥60 days after the last day of supply, or switch to a new ADT). Treatment adherence was assessed at 6 and 12 months (mo) using proportion of days covered (PDC) defined as the sum of non-overlapping days of supply divided by the time period. Results: In total, 173 REL, 266 DEG, and 2,955 GnRH agonist pts were included. Median age was similar across cohorts and the proportion of pts with metastatic disease was slightly lower in GnRH agonist pts (Table). Median time on index ADT was 13.5 (REL), 3.1 (DEG), and 8.8 (GnRH agonist) mo. At 6 mo, persistence was 72.9% (REL), 24.2% (DEG), and 57.3% (GnRH agonist); and the proportion of pts with PDC ≥0.80 was numerically highest in REL and GnRH agonist pts and lowest in DEG. At 12 mo, persistence was 54.8% (REL), 9.9% (DEG), and 39.9% (GnRH agonist); and the proportion of pts with PDC ≥0.80 was also numerically highest in REL and GnRH agonist pts and lowest in DEG (Table). Conclusions: Despite differences in mode of administration, findings indicate that persistence and adherence are similar in pts with PC treated with REL and GnRH agonists while higher than those treated with DEG. Future research is needed to understand the factors associated with persistence and adherence. Table: see text