UPDATED: As FDA clears relugolix for uterine fibroids, Myovant, Pfizer gear up to take on AbbVie in commercial rivalry
Pfizer and Myovant have landed the key approval needed to open up the women’s health side of their relugolix franchise, as the FDA clears a three-in-one pill to treat heavy menstrual bleeding associated with uterine fibroids.
Dubbed Myfembree, the drug — a combination of relugolix, estradiol and norethindrone acetate — is the second in Myovant’s marketed portfolio after Orgovyx, which comprises only relugolix, was approved for prostate cancer in December. Both therapies and a third, for endometriosis, were all part of a $4.2 billion commercial alliance with Pfizer — lending significant muscle as Myovant goes up against AbbVie in a heated marketing battle.
The partners expect to launch Myfembree within the next month. The US wholesale acquisition cost will be $974.54 for 28 tablets, which is good for as many days, a spokesperson said (Orgovyx costs $2,300 per month).
An approval in this indication had been expected given the “strong clinical data” from Phase III studies, according to Baird analyst Brian Skorney. Across two studies, 72.1% and 71.2% of women in the treatment arm achieved a response compared to 16.8% and 14.7% of the placebo groups, meeting the primary endpoint.
A response was defined by a certain level of reduction in menstrual blood loss volume. Heavy menstrual bleeding is often cited as one of the most bothersome symptoms of uterine fibroids, noted Myovant CEO David Marek.
Relugolix works by blocking the hormone known as GnRH. In a deal that illustrated some of the ground rules of his Roivant playbook, Vivek Ramaswamy had picked the drug up from Takeda in exchange for stock in Myovant, and subsequently steered the company to a $218 million IPO in 2016 before flipping it to Sumitomo Dainippon as part of a $3 billion pact.
While its development path has mirrored that of AbbVie’s elagolix, this is the first time the two drugs are targeting the same patients, after AbbVie gave up pushing it in prostate cancer. Myovant says it’s on track to file for approval in endometriosis later this year.
For its part, Myovant is touting the fact that Myfembree will be a once-daily alternative to the two-pills-a-day regimen for AbbVie’s Oriahnn (which similarly contains estradiol and norethindrone acetate to alleviate side effects).