Myovant Sciences and Pfizer announced positive results from the Phase III LIBERTY trial of relugolix combination therapy in women with uterine fibroids.
Relugolix is showing positive results.
Myovant Sciences and Pfizer announced positive results from the Phase III LIBERTY trial of relugolix combination therapy in women with uterine fibroids. The combination therapy is made up of relugolix 40 mg plus estradiol 1.0 mg and norethindrone acetate 0.5 mg. The trial was designed to evaluate continued treatment with the relugolix combo for up to two years.
This particular study, the LIBERTY randomized withdrawal study, was a Phase III trial that enrolled eligible women who completed the LIBERTY long-term extension study. The criteria for eligibility included meeting the responder criteria at one year. Responder criteria were defined as a menstrual blood loss volume of less than 80 mL and a 50% or greater reduction from baseline in menstrual blood loss volume during the last 35 days of treatment measured by the alkaline hematin method.
The women were randomized at Week 52 to once-daily relugolix combination therapy or placebo for a one-year double-blind treatment period. In addition, women on placebo with relapse or heavy menstrual bleeding during the trial were offered re-treatment with open-label relugolix combination therapy.
“Since many women with uterine fibroids spend years struggling to manage their symptoms, there is a critical need for non-invasive long-term treatment options,” said Ayman Al-Hendy, professor of Obstetrics and Gynecology, University of Chicago and LIBERTY Steering Committee Member. “Data from the LIBERTY randomized withdrawal study demonstrate the potential value of continued treatment for women with uterine fibroids, with those receiving relugolix combination therapy in the study experiencing meaningful symptom relief for up to two years.”
Uterine fibroids are noncancerous growth of the uterus. They most often appear during childbearing years. They are not associated with an increased risk of uterine cancer. According to the Mayo Clinic, they can range in size from seedlings to bulky masses that can enlarge or distort the uterus. Many women with fibroids have no symptoms, but common signs and symptoms include heavy menstrual bleeding, menstrual periods longer than a week, pelvic pressure or pain, frequent urination, difficulty emptying the bladder, constipation or backache or leg pains.
“We are pleased to see the positive data from the LIBERTY randomized withdrawal study which support the potential benefit of longer-term treatment with relugolix combination therapy,” said Juan Camilo Arjona Ferreira, chief medical officer of Myovant. “We look forward to making the full data available at a future medical congress.”
The relugolix combination tablet is currently being reviewed by the U.S. Food and Drug Administration (FDA) for uterine fibroids. The agency has a target action date of June 1, 2021.
“Uterine fibroids can affect many women during their lifetime with uncomfortable symptoms, such as heavy menstrual bleeding,” said James Rusnak, senior vice president, chief development officer, Internal Medicine and Hospital, Global Product Development at Pfizer. “We believe that these study results offer encouraging data in support of longer-term efficacy in women suffering from uterine fibroids.”
The two companies inked a partnership deal in late December 2020. Relugolix is a once-daily, oral gonadotropin-release hormone (GnRH) receptor antagonist. The two companies are collaborating in the U.S. and Canada, with Pfizer receiving an exclusive option to develop the drug in oncology outside those two markets except in Asian countries.
They are working to develop and commercialize the drug, under the brand name Orgovyx, in advanced prostate cancer, and if approved, in combination with estradiol 1.0 mg and norethindrone acetate (0.5 mg) in women’s health in the U.S. and Canada. They will split profits and certain expenses for Orgovyx and the relugolix combination.
As part of the deal, Pfizer is paying Myovant up to $4.2 billion, including an upfront payment of $650 million and $200 million in potential regulatory milestones, and tiered sales milestones after hitting specific thresholds up to $2.5 billion in net sales for prostate cancer and also for the combined women’s health indications. If Pfizer chooses to exercise the option in oncology outside the U.S. and Canada, it will pay Myovant another $50 million and double-digit sales royalties.
