Myovant Sciences  and Pfizer Inc. announced that the U.S. Food and Drug Administration (FDA) has approved MYFEMBREE® (relugolix 40 mg, estradiol 1 mg, and norethindrone acetate 0.5 mg) as a one-pill, once-a-day therapy for the management of moderate to severe pain associated with endometriosis in pre-menopausal women, with a treatment duration of up to 24 months. The approval is supported by one-year efficacy and safety data, including 24-week data from the Phase 3 SPIRIT 1 and SPIRIT 2 trials, which were published in The Lancet, and the first 28 weeks of an open-label extension study for eligible women who completed either SPIRIT 1 or SPIRIT 2. MYFEMBREE also is approved for heavy menstrual bleeding associated with uterine fibroids in pre-menopausal women. Myovant and Pfizer will continue to jointly commercialize MYFEMBREE in the U.S. and product is available immediately.

MYFEMBREE offers an effective, once-daily treatment option for the management of moderate to severe pain associated with endometriosis, with a treatment duration of up to 24 months. Endometriosis is a serious chronic condition that requires long-term interventions. Optimization of medical therapies is the recommended treatment paradigm.

MYFEMBREE introduces an option for up to two years of pharmacological management of moderate to severe pain associated with endometriosis in pre-menopausal women. This approval is supported by one-year data from the Phase 3 SPIRIT program, which included two 24-week multi-national clinical studies (SPIRIT 1 and SPIRIT 2) in more than 1,200 women with pain associated with endometriosis, as well as the first 28 weeks of an open-label extension study to assess its longer-term use. Overall, these studies showed MYFEMBREE reduced menstrual pain and non-menstrual pelvic pain with a loss of mean bone mineral density of less than 1% from baseline through one year of treatment.

SPIRIT 1 and 2 each met their co-primary endpoints with 75% of women in the MYFEMBREE group in both studies achieving a clinically meaningful reduction in dysmenorrhea compared with 27% and 30% of women in the placebo groups at Week 24, respectively (both p <0.0001). For non-menstrual pelvic pain, treatment with MYFEMBREE demonstrated a clinically meaningful reduction in pain in 59% and 66% of women, compared with 40% and 43% of women in the placebo groups (p < 0.0001). Adverse reactions occurring in at least 3% of women treated with MYFEMBREE and greater than placebo were: headache, vasomotor symptoms, mood disorders, abnormal uterine bleeding, nausea, toothache, back pain, decreased sexual desire and arousal, arthralgia, fatigue, and dizziness.

The open-label extension study for eligible women who completed either SPIRIT 1 or SPIRIT 2 showed mean bone mineral density loss of less than 1% from baseline through one year of treatment; some patients (19.7%) had losses >3%. Annual bone density measurement is recommended while treating women for endometriosis. MYFEMBREE is available immediately to patients with moderate to severe pain associated with endometriosis with a prescription from their healthcare provider.

Myovant and Pfizer also are committed to supporting women in the U.S. who are prescribed MYFEMBREE throughout their treatment journeys. The MYFEMBREE Support Program provides access support services, including insurance benefits checks, prior authorization support, co-pay support for commercially insured patients, and patient assistance for qualifying uninsured patients. Program terms and conditions apply.

Indications and Usage: MYFEMBREE is indicated in premenopausal women for the management of: Heavy menstrual bleeding associated with uterine leiomyomas (fibroids); and Moderate to severe pain associated with endometriosis. Limitations of Use: Use of MYFEMBREE should be limited to 24 months due to the risk of continued bone loss which may not be reversible.