RCOG 2024

Objective: To evaluate the efficacy and safety of Elagolix 150 mg (Egolix TM 150 manufactured by Sun Pharma) compared to Dienogest 2 mg in alleviating pain associated with endometriosis.Design: Phase-III, randomized, multi-centric, double-blind, double-dummy, parallel-group, active-controlled, comparative, non-inferiority study.Methods: This study included premenopausal female patients with documented endometriosis having pain assessed via numeric rating scale (NRS) 4, dysmenorrhoea scale (DYS) 2, and non-menstrual pelvic pain (NMPP) 2.The study was conducted after receiving regulatory and ethics committee approvals.The patients were randomized (1:1) to either receive Elagolix 150 mg [Test] or Dienogest 2 mg [Comparator] and matching placebos for 24 weeks.For efficacy outcomes NRS, DYS, NMPP, proportion of patients requiring rescue medication and proportion of overall responders on Patient Global Impression of Change (PGI-C) scale were evaluated and for safety outcomes treatment emergent adverse events (TEAEs) were assessed.[Clinical trial registration: CTRI/2023/01/049292] Result: A total of 340 patients were screened out of which 230 patients (115 each in Test arm and Comparator arm) were enrolled.The baseline demographic characteristics were comparable in between treatment arms.The primary endpoint of reduction in NRS score from baseline to Day 85 in Test arm was non-inferior to Comparator arm [Test: -2.43 1.28; Comparator: -2.47 1.26; treatment difference [T-C] (95% CI): 0.04 (-0.3, 0.37)] as the upper 95% CI was below the pre-defined margin of 1.5.The reductions in NRS score from baseline to Day 169 in Test arm was non-inferior to Comparator arm [Test: -4.33 1.46; Comparator: -4.37 1.28, T-C (95% CI): 0.04 (-0.32, 0.4)].The reduction of DYS score and NMPP score from baseline to Day 85 and Day 169 were comparable in both Test and Comparator arms.The proportion of patients requiring rescue medication at Day 169 were comparable in both Test and Comparator arms [Test: 17.7%; Comparator: 17.0%; p > 0.9999].The proportion of overall responders in PGI-C scale at Day 169 were comparable in both Test and Comparator arms [Test: 92.9%; Comparator: 94.6%; p = 0.5928].The incidence of TEAEs were similar in both treatment arms and no serious adverse events were reported. Conclusion:This first-in-the-world active-controlled study demonstrates Elagolix 150 mg tablets to be non-inferior to Dienogest 2 mg tablets in treatment of pain associated with endometriosis as assessed via NRS score from baseline to Day 85 and Day 169 and both treatments were found to be well tolerated.Hence, Elagolix can be considered as valuable treatment option in management of pain associated with endometriosis.