Treatment with Myovant Sciences’ investigative drug relugolix was generally well tolerated and reduced pelvic pain in women with endometriosis, according to results come from a Phase 2 trial and an extension study that evaluated the drug in women with endometriosis-associated pain.
The multicenter, randomized, double-blind, placebo-controlled Phase 2 study (NCT01458301) evaluated the safety of relugolix at three doses (10 mg, 20 mg, and 40 mg) administered orally once daily for 12 weeks in 487 women with endometriosis-associated pain. Effectiveness was assessed using leuprorelin as a drug comparator. The primary endpoint was a reduction of pelvic pain as measured by the Visual Analogue Scale.
An extension study (NCT01452685) looked at the long term safety and effectiveness of relugolix also at three doses (10 mg, 20 mg, and 40 mg), administered orally once daily for a total of 24 weeks in women with endometriosis pain who had participated in the preceding 12-week study. This study included 397 premenopausal women ages 20 and older.
The study’s primary endpoint was the safety including assessment of change in bone mineral density in all patients who were administered the study drug.
The results showed that treatment with relugolix for 24 weeks was generally well tolerated and demonstrated a similar reduction in pelvic pain as leuprorelin in women with endometriosis. Relugolix also demonstrated similar benefits to injectable leuprorelin in the extension study, the researchers reported.
In severe cases of endrometriosis, gonadotropin-releasing hormone (GnRH) agonists such as leuprorelin are used for short-term therapy. But GnRH agonists can cause temporary increases in the secretion of gonadotropin, which can cause an initial worsening of symptoms, Myovant explained on its website.
Relugolix is a GnRH receptor antagonist, leading to the suppression of estrogen in women and improving uterine fibroids and pain from endometriosis, according to the company.
According to a press release the 12-week Phase 2 trial findings were presented at the 13th World Congress on Endometriosis (WCE) in Vancouver, Canada, while the 24-week data from the extension study was presented at the 19th European Congress of Endocrinology (ECE) in Lisbon, Portugal.
At the WCE, Dr. Yutaka Osuga from the University of Tokyo presented an abstract titled “Results from a Phase 2 Study of Relugolix, an Oral Gonadotropin-Releasing Hormone Receptor Antagonist, vs. Placebo in Women with Endometriosis-Associated Pain.”
At the ECE, Osuga presented an abstract titled “Relugolix, an Oral Gonadotropin‐Releasing Hormone Receptor Antagonist, in Women with Endometriosis‐Associated Pain: Phase 2 Safety and Efficacy 24‐Week Results.”
Clinical experience to date, supported by an extensive development program, suggests that relugolix could be an important treatment option for women battling endometriosis and uterine fibroids.