Efficacy and Tolerability of Elagolix in Adolescents and Young Adults with Endometriosis: A Small, Single-Center Retrospective Cohort Study.

STUDY

OBJECTIVE

To evaluate the efficacy and tolerability of the gonadotropin-releasing hormone antagonist elagolix for endometriosis-associated pain symptoms in adolescents and young adults (AYAs)

METHODS

We performed a retrospective cohort study of AYAs with laparoscopically confirmed endometriosis prescribed elagolix between November 2018 and December 2024 at a pediatric tertiary care center. Data from the electronic medical record included demographic and clinical characteristics, previous hormonal therapies, elagolix dose and use of add-back therapy, symptom response, and adverse effects. Primary outcomes were patient-reported symptom improvement and treatment discontinuation. The study was deemed IRB exempt.

RESULTS

Nineteen patients began taking elagolix, median age 18 years (IQR = 16-21). Endometriosis stage was I in 8 patients (42%), II in 10 (52%), and III in 1 (5%). All patients had previously tried 2 or more hormonal therapies, most commonly the levonorgestrel intrauterine device and norethindrone acetate (68% each). Of patients treated with elagolix, add-back therapy was used in 58%, primarily norethindrone acetate. Overall, 53% reported some improvement; dysmenorrhea and pelvic pain improved in 42% and 53%, respectively. Adverse events included persistent pelvic pain (37%), unpredictable bleeding (26%), and mood changes (16%). No serious adverse events occurred. Discontinuation occurred in 95% of patients, most commonly due to persistent pain and mood changes. The median treatment duration was 5.5 months (IQR = 3-12).

CONCLUSION

In this small cohort, elagolix was associated with modest symptom improvement but high discontinuation rates in AYAs with endometriosis. Larger prospective studies are needed to define its role in the long-term management of adolescent endometriosis.