Astellas’ Phase 3 STARLIGHT 2 trial in Japan shows fezolinetant significantly reduced menopausal vasomotor symptoms versus placebo, with a favorable safety profile, supporting planned regulatory filing
Written By: Pharmacally Medical News Desk
Astellas Pharma Inc. has reported positive topline results from the Phase 3 STARLIGHT 2 pivotal study evaluating fezolinetant for the treatment of vasomotor symptoms associated with menopause in Japanese women. The trial met its primary endpoint, showing a statistically significant reduction in the frequency of vasomotor symptoms compared with placebo.
Topline Efficacy Results
STARLIGHT 2 enrolled 410 Japanese women experiencing moderate to severe vasomotor symptoms, including hot flashes and night sweats. Treatment with fezolinetant 30 mg and 45 mg once daily led to a statistically significant improvement in the frequency of vasomotor symptoms from baseline to week 8 versus placebo. These findings confirm the clinical benefit of a nonhormonal oral option in a population where treatment choices remain limited.
Safety and Tolerability
Fezolinetant was generally well tolerated in the study. Serious treatment-emergent adverse events were reported in fewer than 4% of patients, and the overall safety profile was consistent with what has been observed in previous global studies of the drug. No new safety signals were identified during the 12-week treatment period.
Regulatory and Development Plans
Astellas plans to submit the full STARLIGHT 2 data for presentation at a scientific congress and for publication in late 2026. The results will support a regulatory filing for fezolinetant in Japan, marking a key step toward expanding access to nonhormonal therapy for menopausal symptoms in the region. The company has already factored the expected impact of these results into its financial forecast for the fiscal year ending March 31, 2025.
Global Context of Fezolinetant
Fezolinetant received its first approval in May 2023 from the U.S. Food and Drug Administration under the brand name VEOZAH™. Since then, the drug has been approved in 45 countries and is commercially available in 36 markets worldwide.
About the STARLIGHT 2 Trial
STARLIGHT 2 (NCT06206408) is a randomized, double-blind, placebo-controlled, parallel-group, multicentre Phase 3 study conducted in Japan. Participants were randomized to receive fezolinetant 30 mg, fezolinetant 45 mg, or placebo once daily for 12 weeks. The primary endpoint was the mean change in vasomotor symptom frequency from baseline to week 8.
About Fezolinetant
Fezolinetant is an investigational, oral, nonhormonal therapy designed to address vasomotor symptoms of menopause. It works by blocking neurokinin B signalling on kisspeptin/neurokinin/dynorphin neurons, helping rebalance the brain’s temperature regulation center in the hypothalamus. This mechanism reduces the frequency and intensity of hot flashes and night sweats without the use of hormone therapy.
References
Phase 3 Trial of Fezolinetant in Japan Shows Topline Results for Treatment of Vasomotor Symptoms (VMS) Associated with Menopause, 03 February 2026, https://newsroom.astellas.com/2026-02-03-phase-3-trial-of-fezolinetant-in-japan-shows-topline-results-for-treatment-of-vasomotor-symptoms-vms-associated-with-menopause
A Study to Confirm if Fezolinetant Helps Reduce Hot Flashes in Japanese Women Going Through Menopause (Starlight 2), ClinicalTrials.gov ID NCT06206408, https://clinicaltrials.gov/study/NCT06206408