Relugolix, a novel oral gonadotropin-releasing hormone antagonist, in the treatment of pain symptoms associated with uterine fibroids: a randomized, placebo-controlled, phase 3 study in Japanese women

Abstract

To investigate the efficacy and safety of the oral gonadotropin-releasing hormone receptor antagonist, relugolix, in patients experiencing uterine fibroid-associated pain. Phase 3, multicenter, randomized, double-blind, placebo-controlled study. Medical centers. Premenopausal Japanese women (N = 65) experiencing moderate-to-severe uterine fibroid-associated pain with a maximum Numerical Rating Scale (NRS) score of ≥4 were randomized and completed the study. Once-daily 40mg relugolix (n = 33) or placebo (n = 32) for 12weeks. Primary end point: proportion of patients with a maximum NRS score of ≤1 during the 28-day period before the final dose of study drug. Secondary end points: proportion of patients with no pain (NRS = 0) and percentage of days without pain during the 28-day period before the final dose of study drug; adverse events. More patients receiving relugolix versus placebo achieved a maximum NRS score of ≤1 during the 28-day period before the final dose of study drug (57.6% vs. 3.1%). Similarly, more patients receiving relugolix versus placebo achieved a maximum NRS score of 0 (48.5% vs. 3.1%) and experienced more days without pain (96.4% vs. 71.4%). More patients receiving relugolix versus placebo experienced treatment-emergent adverse events (TEAEs; 87.9% vs. 56.3%); however, the rate of treatment discontinuation was low and not different between groups. Most TEAEs were mild to moderate in intensity. TEAEs (≥10%) included hot flush, metrorrhagia, hyperhidrosis, and menorrhagia, consistent with relugolix's mechanism of action, and viral upper respiratory tract infection. Relugolix improved uterine fibroid-associated pain and was well tolerated. NCT02655224. JapicCTI-163127.