Oral GnRH antagonists effective in endometriosis-related pain, dysmenorrhea

Oral gonadotropin-releasing hormone (GnRH) antagonists help relieve pain in women with endometriosis or dysmenorrhea, according to the results of a meta-analysis.

Researchers conducted a systematic review of available literature evaluating the effects of oral GnRH antagonists in endometriosis patients with moderate or severe pain. They searched multiple electronic databases for relevant studies. The outcomes examined were endometriosis-associated pain, dysmenorrhea, dyspareunia, and noncyclic pelvic pain reduction.

The Cochrane Risk of Bias tool 2 was used to assess the risk of bias in the included studies, while a Bayesian random-effects network meta-analysis was performed for indirect comparisons. Treatment ranking was carried out through the surface under the cumulative ranking curve. Finally, the certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development and Evaluation framework.

The search yielded five studies and six randomized controlled trials, involving a total of 2,796 women and 10 different doses of oral GnRH antagonist treatments, for inclusion. All studies were deemed to have a low risk of bias. Nearly all efficacy- and safety-related outcomes showed a dose-response relationship.

In terms of endometriosis-associated pain, the top three treatments were elagolix 400 mg, linzagolix 75 mg, and linzagolix 200 mg, with mean differences of −1.26 (95 percent credible interval [CrI], −1.70 to −0.79), −0.98 (95 percent CrI, −1.84 to −0.15), and −0.98 (95 percent CrI, −1.90 to −0.064), respectively.

The three top ranked treatments with respect to reducing dysmenorrhea were relugolix 40 mg, elagolix 400 mg, and relugolix 20 mg. The corresponding mean differences were −1.60 (95 percent CrI, −2.07 to −1.14), −1.25 (95 percent CrI, −1.56 to −0.95), and −1.10 (95 percent CrI, −1.59 to −0.62).

Meanwhile, relugolix 40 and 20 mg and elagolix 400 mg were associated with a significantly increased frequency of adverse events, with odds ratios of 6.88 (95 percent CrI, 2.18–24.58), 1.60 (95 percent CrI, 0.62–4.13), and 1.85 (95 percent CrI, 1.05–3.30), respectively.