Bayer’s hot flash drug candidate has hit the mark in a phase 3 breast cancer trial, potentially positioning the German drugmaker to get the jump on Astellas’ rival drug Veozah.
Astellas won the race to win approval for the treatment of hot flashes associated with menopause. The FDA approved Astellas’ NK-3 antagonist Veozah in that setting in May 2023. Bayer only had its filing for approval of the NK-1 and NK-3 antagonist elinzanetant accepted for review in October 2024. Yet, while Bayer is playing catch-up in the menopause space, the German drugmaker has stolen a lead in cancer.
Thursday, Bayer shared top-line data from a phase 3 trial that tested elinzanetant in women on adjuvant endocrine therapy for breast cancer. The anticancer therapy can cause hot flashes, known medically as vasomotor symptoms, creating an overlap with the symptoms experienced by menopausal women.
Investigators randomized 474 recipients of adjuvant endocrine therapy to take elinzanetant or placebo once daily and asked them to record information about hot flashes. After four and 12 weeks of treatment, Bayer saw significant reductions in hot flashes compared to placebo, causing the trial to hit its co-primary endpoints.
The trial also hit all secondary endpoints. Bayer linked elinzanetant to reductions in the severity of hot flashes at weeks 4 and 12. Reductions in the frequency of hot flashes were seen at Week 1, and the effect was maintained over the study period. Bayer reported improvements in sleep disturbances and quality of life, too. The safety profile over 52 weeks was “generally consistent” with other data on elinzanetant.
The data drop comes around four months after Astellas dosed the first patient in a phase 3 trial of its rival hot flash drug. Astellas is working to enroll about 540 women on adjuvant endocrine therapy with a view to reaching the primary completion of the study in October 2026.
While Bayer already has phase 3 data on elinzanetant in the setting, the results come from a study that was conducted outside of the U.S. Europe provided most of the trial sites, although Bayer also activated some centers in Canada and Israel. The ClinicalTrials.gov page for Astellas’ trial currently only lists three study sites, all of which are in Canada.