Myovant’s Relugolix Combo Therapy Positive for Uterine Fibroids
Myovant Sciences announced positive data from LIBERTY 1, one of its two Phase III trials of once daily relugolix combination therapy in uterine fibroids.
The trial met its primary endpoint and six key secondary endpoints. For the primary endpoint, 73.4% of patients receiving once daily doses of relugolix hit the responder criteria comped to 18.9% of women who received placebo. The response was defined as menstrual blood loss volume of less than 80 mL and a 50% or greater decrease from baseline in menstrual blood loss volume during the last 35 days of the 24-week treatment. On average, women receiving the relugolix combination therapy had an 84.3% reduction in menstrual blood loss from baseline, which was a key secondary endpoint.
Patients receiving the drug also maintained bone mineral density to levels comparable to those on placebo over 24 weeks. The therapy was generally well tolerated.
Uterine fibroids are noncancerous tumors that develop in or on the walls of the uterus. They are some of the most common reproductive tract tumors in women. Although benign, the symptoms include abnormal uterine bleeding, heavy or painful periods, anemia, abdominal pain, backache, increased abdominal girth and bloating, urinary frequency or retention, constipation or painful defecation, pregnancy loss, painful intercourse and sometimes infertility.
Relugolix is a once daily oral gonadotropin-releasing hormone (GnRH) receptor antagonist. It decreases ovarian estradiol production. This hormone stimulates the growth of uterine fibroids.
Myovant has two Phase III trials, LIBERTY 1 and 2, of relugolix combination therapy (relugolix 40 mg plus estradiol 1.0 mg and norethindrone acetate 0.4 mg) in women with uterine fibroids and heavy menstrual bleeding.
LIBERTY 1 enrolled 388 women. LIBERTY 2 enrolled 382 women.
“We are incredibly pleased with the positive results of this first Phase III study demonstrating a clinically meaningful response in a high proportion of women while maintaining bone health,” stated Lynn Seely, president and chief executive officer of Myovant.
Seely went on to say, “These results substantiate our once daily oral combination therapy approach. The improvements in symptoms most relevant to women, such as reduction in menstrual blood loss and pain, and improvement in quality of life are particularly exciting. We look forward to the possibility of bringing a new treatment option, suitable for long-term use, to the millions of women suffering from this debilitating disease.”
Secondary endpoints included mean change in menstrual blood loss from baseline to week 24, decrease in pain at baseline, improvement in quality of life, amenorrhea defined as no or negligible blood loss, improvement in anemia in women with anemia at baseline and reduction in uterine volume.
The adverse events were comparable between the relugolix combination group and placebo cohort, 62% and 66%, respectively. In the group receiving the combo therapy, 5% discontinued treatment early because of adverse events compared to 4% in the placebo group. The only side effect in the relugolix combination arm that occurred in at least 10% of women and more frequently than in the placebo group was hot flush (11% compared to 8%).
The company is planning a readout from its second Phase III trial in the third quarter. If that provides positive results, the company expects to file with the U.S. Food and Drug Administration in the fourth quarter.
AbbVie and Neurocrine Biosciences are working on a Phase III of elagolix for uterine fibroids, as is ObsEva, for its OBE2109. Allergan’s Esmya, however, was rejected in August 2018 over safety concerns.