TOKYO, February 19, 2021 – Astellas Pharma Inc. (TSE: 4503, President and CEO: Kenji Yasukawa, Ph.D., “Astellas”) today announced positive topline results from the Phase 3 pivotal SKYLIGHT 1™ and SKYLIGHT 2™ clinical trials for fezolinetant, an investigational oral, nonhormonal compound being studied for the treatment of moderate to severe vasomotor symptoms (VMS) – i.e., hot flashes associated with menopause. 

Both trials met all four co-primary endpoints showing statistically significant reduction from baseline in the frequency and severity of moderate to severe VMS to week 4 and week 12 for women who received fezolinetant 30 and 45 mg once-daily (QD) versus placebo. Serious treatment emergent adverse events (TEAE) occurred in less than 2 percent of patients and the most common TEAE was headache. SKYLIGHT 1 and SKYLIGHT 2 are ongoing studies, with patients completing a treatment duration for 52 weeks. Detailed results will be submitted for publication and for consideration at upcoming medical meetings following the 52-week analyses. 

“We are encouraged by these results for fezolinetant, which mark the first Phase 3 data in a new category of selective neurokinin-3 (NK3)-targeted treatments for moderate to severe vasomotor symptoms,” said Salim Mujais, M.D., Senior Vice President and Therapeutic Area Head, Medical Specialties, Astellas. “Vasomotor symptoms can add a significant burden and impact quality of life for women. We are hopeful that with fezolinetant, we will be able to deliver a novel nonhormonal treatment option.”

VMS are the most common symptoms associated with menopause, affecting more than 50 percent of women 40 to 64 years of age.1,2 VMS can have a considerable effect on a woman's comfort and sleep which can lead to fatigue, mood changes, and effect work and relationships.1,3

Fezolinetant is an investigational, selective neurokinin-3 receptor (NK3R) antagonist that blocks neurokinin B (NKB) binding on the kisspeptin/neurokinin/dynorphin (KNDy) neuron to moderate neuronal activity in the thermoregulatory center in the hypothalamus of the brain to treat VMS associated with menopause. If approved by regulatory authorities, fezolinetant would be a first-in-class, nonhormonal treatment option to reduce the frequency and severity of VMS associated with menopause.   

SKYLIGHT 1 and SKYLIGHT 2 are double-blinded and placebo-controlled studies evaluating 30 and 45 mg fezolinetant administered once-daily for the first 12 weeks followed by 40-week active treatment extension periods.


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