Phase 3b Trial of Fezolinetant Shows Positive Topline Results for Treatment of VMS Due to Menopause

Study evaluated 24-week efficacy and safety of Astellas' fezolinetant in women considered unsuitable for hormone therapy

TOKYO, June 27, 2023 /PRNewswire/ -- Astellas Pharma Inc. (TSE: 4503, President and CEO: Naoki Okamura, "Astellas") today announced positive topline results from the Phase 3b DAYLIGHT clinical trial for fezolinetant, an investigational oral, nonhormonal compound being studied for the treatment of moderate to severe vasomotor symptoms (VMS) due to menopause. VMS, characterized by hot flashes and/or night sweats, are common symptoms of menopause.1,2

The study, comprised of more than 450 women considered unsuitable for hormone therapy, met the primary objective showing statistically significant reduction from baseline in the frequency of moderate to severe VMS to week 24 for fezolinetant 45 mg once daily versus placebo. Serious treatment emergent adverse events (TEAE) occurred in less than 5% of patients, and the most common TEAEs were COVID-19 and headache. Detailed results will be submitted for publication and for consideration at an upcoming medical meeting.

Marci English, Vice President, Head of BioPharma Development, Astellas
"We are delighted the initial assessment of the DAYLIGHT study further validates the role of fezolinetant in reducing the frequency of moderate to severe VMS due to menopause. These 24-week placebo-controlled data add to our growing base of clinical evidence established in the SKYLIGHT studies and provide additional insights on the safety and effectiveness of fezolinetant in women who cannot or choose not to take hormone therapy."

Fezolinetant was approved as VEOZAH™ by the U.S. Food and Drug Administration (FDA) in May 2023, and Astellas is pursuing regulatory approval for fezolinetant in several other countries and regions, including Europe. The DAYLIGHT study generated additional efficacy and safety data to primarily support health technology assessment (HTA) and reimbursement dossiers throughout Europe.

Astellas has already reflected the impact from this result in its financial forecast of the current fiscal year ending March 31, 2024.

DAYLIGHT (NCT05033886) is a Phase 3b, randomized, double-blind, placebo-controlled, 24-week study to assess the efficacy and safety of fezolinetant in menopausal women aged 40-65 suffering from moderate to severe VMS and considered unsuitable for hormone therapy. A total of 453 women were enrolled at 69 sites in Canada, Europe and Turkey.

About the BRIGHT SKY™ Phase 3 Program
The BRIGHT SKY pivotal trials, SKYLIGHT 1™ (NCT04003155) and SKYLIGHT 2™ (NCT04003142), enrolled over 1,000 women with moderate to severe VMS. The trials are double-blinded, placebo-controlled for the first 12 weeks followed by a 40-week treatment extension period. Women were enrolled at over 180 sites within the U.S., Canada and Europe. SKYLIGHT 4™ (NCT04003389) is a 52-week double-blinded, placebo-controlled study designed to investigate the long-term safety of fezolinetant. For SKYLIGHT 4, over 1,800 women with VMS were enrolled at over 180 sites within the U.S., Canada and Europe.

About Fezolinetant
Fezolinetant is a neurokinin 3 (NK3) receptor antagonist FDA approved in the U.S. for the treatment of moderate to severe vasomotor symptoms (VMS) due to menopause. Fezolinetant is not a hormone. VMS are the feelings of warmth in the face, neck, and chest, or sudden intense feelings of heat and sweating ("hot flashes" or "hot flushes"). Fezolinetant works by blocking neurokinin B (NKB) binding on the kisspeptin/neurokinin B/dynorphin (KNDy) neuron to modulate neuronal activity in the thermoregulatory center of the brain (the hypothalamus) to reduce the frequency and severity of moderate to severe VMS due to menopause.

U.S. Important Safety Information

Do not use VEOZAH if you:

  • have cirrhosis.
  • have severe kidney problems or kidney failure.
  • are taking certain medicines called CYP1A2 inhibitors. Ask your healthcare provider if you are not sure.

Before you use VEOZAH, tell your healthcare provider about all of your medical conditions, including if you:

  • have liver disease or problems.
  • have kidney problems.
  • have any medical conditions that may become worse while you are using VEOZAH.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. VEOZAH may affect the way other medicines work, and other medicines may affect how VEOZAH works.

VEOZAH can cause serious side effects, including:

  • increased liver blood test values. Your healthcare provider will do a blood test to check your liver before you start taking VEOZAH. Your healthcare provider will also do this blood test at month 3, month 6, and month 9 after you start taking VEOZAH.

Call your healthcare provider right away if you have the following signs and symptoms of liver problems:

  • nausea
  • vomiting
  • yellowing of the eyes or skin (jaundice)
  • pain in the right upper stomach (abdomen)

The most common side effects of VEOZAH include:

  • stomach (abdominal) pain
  • diarrhea
  • difficulty sleeping (insomnia)
  • back pain
  • hot flashes or hot flushes

These are not all the possible side effects of VEOZAH. Tell your healthcare provider if you have any side effect that bothers you or does not go away.

Call your healthcare provider for medical advice about side effects. You may report side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088.

For more information, please see the full Prescribing Information and Patient Product Information for VEOZAH (fezolinetant).

About Astellas
Astellas Pharma Inc. is a pharmaceutical company conducting business in more than 70 countries around the world. We are promoting the Focus Area Approach that is designed to identify opportunities for the continuous creation of new drugs to address diseases with high unmet medical needs by focusing on Biology and Modality. Furthermore, we are also looking beyond our foundational Rx focus to create Rx+® healthcare solutions that combine our expertise and knowledge with cutting-edge technology in different fields of external partners. Through these efforts, Astellas stands on the forefront of healthcare change to turn innovative science into VALUE for patients. For more information, please visit our website at

Cautionary Notes
In this press release, statements made with respect to current plans, estimates, strategies and beliefs and other statements that are not historical facts are forward-looking statements about the future performance of Astellas. These statements are based on management's current assumptions and beliefs in light of the information currently available to it and involve known and unknown risks and uncertainties. A number of factors could cause actual results to differ materially from those discussed in the forward-looking statements. Such factors include, but are not limited to: (i) changes in general economic conditions and in laws and regulations, relating to pharmaceutical markets, (ii) currency exchange rate fluctuations, (iii) delays in new product launches, (iv) the inability of Astellas to market existing and new products effectively, (v) the inability of Astellas to continue to effectively research and develop products accepted by customers in highly competitive markets, and (vi) infringements of Astellas' intellectual property rights by third parties. Information about pharmaceutical products (including products currently in development) which is included in this press release is not intended to constitute an advertisement or medical advice.


1 Utian WH. Psychosocial and socioeconomic burden of vasomotor symptoms in menopause: a comprehensive review. Health Qual Life Outcomes. 2005;3:47.
2 Jones RE, Lopez KH, eds. Human Reproductive Biology. 4th ed. Waltham, MA: Elsevier, 2014:120.

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SOURCE Astellas Pharma Inc.

Company Codes: Tokyo:4503, OTC-PINK:ALPMY

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