More than half of elinzanetant’s sleep benefits occur independently of its effect on nighttime hot flashes, according to a pooled analysis of four clinical trials presented at the SLEEP 2026 Annual Meeting. The finding suggests the drug, sold under the brand name Lynkuet, may work through a separate mechanism to improve sleep in menopausal women.
The analysis, led by Pauline M. Maki, PhD, used data from the phase 3 OASIS-1, -2, and -3 trials and the phase 2 NIRVANA trial, covering 1,345 postmenopausal women. They applied a longitudinal causal mediation analysis to separate elinzanetant’s total sleep effect into two components: improvement independent of nighttime vasomotor symptom reduction, and improvement mediated through vasomotor symptom reduction.
The total treatment effect on PROMIS Sleep Disturbance scores was −4.92 (95% CI, −5.73 to −4.12). Of that, 54.3% came from the direct effect (NDE: −2.67; 95% CI, −3.28 to −2.07), with the rest mediated through nighttime vasomotor symptom reduction (NIE: −2.25; 95% CI, −2.81 to −1.69).
Pauline M. Maki said about half of the treatment benefit of elinzanetant on sleep is actually direct. She identified the NK1 receptor as a potentially novel mechanism for sleep disturbance in midlife women, separate from the vasomotor pathway targeted by NK3 blockade.
The finding held across trial populations with different enrollment rules. The OASIS-3 trial had no minimum hot flash requirement, which Maki said generalizes more broadly to the clinical range of menopausal symptoms than trials requiring 35 or 50 or more hot flashes per week.
Pauline M. Maki said the fact that women didn’t have to meet a minimum threshold for the number of hot flashes does suggest that maybe it’s not the magnitude of the hot flash burden that determines the benefits of elinzanetant on sleep. Maybe it’s a general benefit that may not be dependent on the severity of those symptoms.
This matters for the millions of women whose sleep problems persist even when hot flashes are controlled. Standard hormone therapy and other vasomotor symptom-targeted treatments often leave the sleep disruption untouched, and the new data suggests elinzanetant might fill that gap by acting on a different biological pathway—one that affects sleep architecture directly rather than through temperature regulation, which is related to collaborative care approaches.
Maki’s broader point was that hot flashes account for only about one third of the total time menopausal women spend awake at night. The remaining two thirds reflects other menopause-associated changes to sleep architecture that occur independently of vasomotor events.
She said two thirds of the time that they’re awake is really associated with just some phenomenon associated with menopause. Elinzanetant’s direct sleep benefit may be acting on precisely that component—the sleep disruption that vasomotor symptom-targeted treatment alone cannot reach.
The analysis was published in the journal Sleep as part of the SLEEP 2026 meeting proceedings. The drug’s dual mechanism—acting on both NK1 and NK3 receptors—appears to give it a broader effect on menopausal sleep than drugs targeting hot flashes alone, which is important for overall well-being.
