Treatment Patterns of Goserelin 3.6 mg Once Every 4 Weeks and 10.8 mg Once Every 12 Weeks in Women With Breast Cancer: A Real-World Analysis of Patients in the United States.

purposeGoserelin is a gonadotropin-releasing hormone agonist for ovarian function suppression in the treatment of pre- and perimenopausal patients with breast cancer and for the preservation of ovarian function during chemotherapy. Goserelin is available in doses of 3.6 mg once every 4 weeks or 10.8 mg once every 12 weeks. This study used US real-world evidence to characterize goserelin treatment patterns.

methodsElectronic health record data of adults with a history of breast cancer and ≥2 goserelin prescriptions between January 1, 2017, and December 31, 2022, were identified through TriNetX. Patient demographics and treatment patterns were examined.

resultsOverall, 3,620 US patients were identified: 2,870 treated with goserelin 3.6 mg once every 4 weeks, 410 treated with 10.8 mg once every 12 weeks, and 340 switched from 3.6 mg once every 4 weeks to 10.8 mg once every 12 weeks. Peak utilization of 10.8 mg once every 12 weeks (36.6%) and dose switching to 10.8 mg once every 12 weeks (26.5%) occurred in 2020. Patients who switched to 10.8 mg once every 12 weeks had the longest median treatment duration (776 days), compared with the 3.6 mg once every 4 weeks and 10.8 mg once every 12 weeks cohorts (264 and 429 days, respectively). Of patients who switched, 65% were still being treated after 2 years, compared with 30% and 40% treated with 3.6 mg once every 4 weeks only or 10.8 mg once every 12 weeks only, respectively. Patients initially treated with or who switched to 10.8 mg once every 12 weeks were more adherent (64.4%-75.0%), compared with patients treated with 3.6 mg once every 4 weeks (45.4%).

conclusionTreatment with goserelin 10.8 mg once every 12 weeks is associated with greater adherence and longer treatment duration, compared with 3.6 mg once every 4 weeks in patients with breast cancer in the United States.