Safe and effective nonhormonal treatments for menopausal vasomotor symptoms (VMS) are needed.

To evaluate the efficacy and safety of elinzanetant, a selective neurokinin-1,3 receptor antagonist, for the treatment of moderate to severe menopausal vasomotor symptoms.

Two randomized double-blind phase 3 trials (OASIS 1 and 2) included postmenopausal participants aged 40 to 65 years experiencing moderate to severe vasomotor symptoms (OASIS 1: 77 sites in the US, Europe, and Israel from August 27, 2021, to November 27, 2023, and OASIS 2: 77 sites in the US, Canada, and Europe from October 29, 2021, to October 10, 2023).

Once daily oral elinzanetant, 120 mg, for 26 weeks or matching placebo for 12 weeks followed by elinzanetant, 120 mg, for 14 weeks.

Primary end points included mean change in frequency and severity of moderate to severe vasomotor symptoms from baseline to weeks 4 and 12, measured by the electronic hot flash daily diary. Secondary end points included Patient-Reported Outcomes Measurement Information System Sleep Disturbance Short Form 8b total T score and Menopause-Specific Quality of Life questionnaire total score from baseline to week 12.

Eligible participants (mean [SD] age, OASIS 1: 54.6 [4.9] years; OASIS 2: 54.6 [4.8] years) were randomized to elinzanetant (OASIS 1: n = 199; OASIS 2: n = 200) or placebo (OASIS 1: n = 197; OASIS 2: n = 200). A total of 309 (78.0%) and 324 (81.0%) completed OASIS 1 and 2, respectively. For the elinzanetant and placebo groups, the baseline mean (SD) VMS per 24 hours were 13.4 (6.6) vs 14.3 (13.9) (OASIS 1) and 14.7 (11.1) v 16.2 (11.2) (OASIS 2). Baseline VMS severity was 2.6 (0.2) vs 2.5 (0.2) (OASIS 1) and 2.5 (0.2) vs 2.5 (0.2) (OASIS 2). Elinzanetant significantly reduced VMS frequency at week 4 (OASIS 1: -3.3 [95% CI, -4.5 to -2.1], P < .001; OASIS 2: -3.0 [95% CI, -4.4 to -1.7], P < .001) and at week 12 (OASIS 1: -3.2 [95% CI, -4.8 to -1.6], P < .001; OASIS 2: -3.2 [95% CI, -4.6 to -1.9], P < .001). Elinzanetant also improved VMS severity at week 4 (OASIS 1: -0.3 [95% CI, -0.4 to -0.2], P < .001; OASIS 2: -0.2 [95 CI, -0.3 to -0.1], P < .001) and week 12 (OASIS 1: -0.4 [95% CI, -0.5 to -0.3], P < .001; OASIS 2: -0.3 [95% CI, -0.4 to -0.1], P < .001). Elinzanetant improved sleep disturbances and menopause-related quality of life at week 12, and the safety profile was favorable.

Elinzanetant was well tolerated and efficacious for moderate to severe menopausal VMS.

ClinicalTrials.gov Identifier: OASIS 1: NCT05042362, OASIS 2: NCT05099159.