TOKYO, March 7, 2022 – Astellas Pharma Inc. (TSE: 4503, President and CEO: Kenji Yasukawa, Ph.D., “Astellas”) today announced topline results from the Phase 3 SKYLIGHT 4™ clinical trial investigating the long-term safety of fezolinetant, an investigational oral, nonhormonal compound being studied for the treatment of moderate to severe vasomotor symptoms associated with menopause (VMS) which will support future regulatory filing submissions. VMS, characterized by hot flashes (also called hot flushes) and/or night sweats, are common symptoms of menopause.1,2

SKYLIGHT 4 is a randomized, placebo-controlled, double-blind Phase 3 clinical trial in over 1,800 women investigating the long-term (52-week) safety of fezolinetant in women seeking treatment for relief of VMS associated with menopause. The study’s primary objectives were to evaluate the effect of fezolinetant on endometrial health and the long-term safety and tolerability of fezolinetant. The primary endpoint assessing endometrial health was achieved and the most common treatment emergent adverse events (TEAE) were headache and COVID-19, consistent with placebo. The topline data further characterize the long-term safety profile of fezolinetant and will inform future regulatory filings. Detailed results will be submitted for publication and for consideration at upcoming medical meetings.

“Based on our initial assessment, we are pleased with the outcome of the SKYLIGHT 4 study, which further characterizes the long-term safety of fezolinetant,” said Nancy Martin, M.D., PharmD, Vice President, Global Medical Head, Medical Specialties, Astellas. “With these fezolinetant data, we are hopeful that we will have the opportunity to deliver a first-in-class, nonhormonal treatment option for moderate to severe VMS associated with menopause.”

“Vasomotor symptoms are often reported as the most bothersome symptoms of menopause, yet there has been very little innovation in this therapeutic area,” said Genevieve Neal-Perry, M.D., Ph.D., Chair, UNC School of Medicine Department of Obstetrics and Gynecology. “I am excited by the potential of a new nonhormonal treatment option for women experiencing moderate to severe VMS associated with menopause.”

The SKYLIGHT 4 findings, along with the results from two pivotal Phase 3 clinical trials, SKYLIGHT 1™ and SKYLIGHT 2™, will provide the foundational data for regulatory submissions in the U.S. and Europe.

Fezolinetant is an investigational selective neurokinin-3 (NK3) receptor antagonist. The safety and efficacy of fezolinetant are under investigation and have not been established. 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.


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