FDA Issues New Liver Injury Warning for Astellas' Veozah

The FDA has issued a new warning regarding Astellas Pharma's hot flash therapy, Veozah (fezolinetant), following a postmarketing safety review. This warning addresses the risk of "rare but serious" liver injury observed in a patient who showed elevated liver blood test values after approximately 40 days of treatment. Consequently, the drug's label now recommends enhanced liver monitoring protocols for patients.

Veozah, a non-hormonal small molecule blocker, specifically targets the NK3 receptor, which is involved in hormonal signaling related to the menstrual cycle. This mechanism helps reduce the frequency and intensity of hot flashes and night sweats for menopausal women. The FDA had initially approved Veozah for this use in May 2023.

The updated label for Veozah advises healthcare professionals to conduct more frequent blood liver tests. These should include monthly screenings for the first two months, followed by additional tests at three, six, and nine months. Additionally, hepatic testing should be done before initiating treatment. Patients experiencing symptoms indicative of liver problems—such as fatigue, jaundice, nausea, vomiting, unusual itching, and light-colored stools—should discontinue Veozah immediately and consult their healthcare provider.

Despite this setback to Veozah’s safety profile, analysts from Jeffries believe that the new warning will not significantly impact the drug's market performance. They noted that while the additional liver tests may place a greater burden on patients, it is unlikely to diminish overall demand for Veozah.

Astellas Pharma has been actively promoting Veozah, unveiling new data from Phase IIIb studies in December 2023. These studies demonstrated statistically significant improvements in moderate to severe vasomotor symptoms at 24 weeks compared to a placebo. Veozah also showed a reduction in sleep disturbances for these patients. Astellas indicated that these findings would support reimbursement negotiations in Europe.

Competition in the non-hormonal treatment space for menopausal symptoms is growing. Bayer is developing a rival drug, elinzanetant, a small molecule dual inhibitor of the NK1 and NK3 receptors. Bayer acquired this drug by purchasing KaNDy Therapeutics for $425 million upfront in August 2020. In May 2024, Bayer released positive data from its Phase III OASIS 1 and OASIS 2 studies, showing that elinzanetant effectively reduced the frequency of hot flashes, improved sleep disturbances, and enhanced menopause-related quality of life.

In summary, while the FDA’s new warning about Veozah poses additional safety considerations, it is not expected to significantly impact Astellas Pharma's market position. The company continues to advance its product with promising clinical data, even as competitors like Bayer introduce alternative treatments for menopausal symptoms.