Interpreting elinzanetant data and benefits on sleep in postmenopausal women

Multiple data presented at the SLEEP 2026 Annual Meeting in Baltimore, Maryland, highlighted positive sleep impacts with elinzanetant (Lynkuet) treatment in postmenopausal women, including from the phase 2 NIRVANA study (NCT06112756).^1,2

In a previous discussion, abstract co-author Fiona Baker, PhD, director, Human Sleep Research Program, SRI International, discussed key takeaways and modalities regarding how the NK3 receptor antagonist reduced wakefulness after sleep onset (WASO). Click here to learn more about the data and the 3 modalities in which WASO was measured.

Key findings from NIRVANA:

The NIRVANA trial randomized 110 postmenopausal women with PSG-confirmed WASO of at least 30 minutes and at least 20 moderate-to-severe vasomotor symptoms (VMS) per week to elinzanetant 120 mg (n = 55) or placebo (n = 55) once daily for 12 weeks. PSG assessments were conducted at baseline, week 4, and week 12 (2 consecutive nights per timepoint). The Sleepiz One+, a contactless home-monitoring device, was used in a subset of participants (elinzanetant: n = 33, placebo: n = 33), whereas sleep diary data were collected nightly across all participants.

Across all 3 modalities, overall treatment effects over 12 weeks favored elinzanetant. By PSG, baseline mean WASO was 74.7 minutes (SD 34.8) for elinzanetant and 82.8 minutes (SD 34.4) for placebo.

“Overall treatment effect favored elinzanetant (least squares [LS] mean difference: -10.1 minutes; unadjusted 95% confidence interval [CI]: -18.5, -1.6),” the authors wrote.

Breaking down elinzanetant data to patients

In the discussion above, Baker further explains what the data means for impacts not only on sleep, but also on the downstream impacts on the next day. Baker explains how the NIRVANA trial data are encouraging, as they build on strong data from the OASIS clinical program.

Contemporary OB/GYN:

The absolute WASO reductions range from roughly 8 to 18 minutes depending on the modality. How should clinicians frame those numbers for patients in terms of real-world impact on sleep and daytime function?

Fiona Baker, PhD:

When we consider menopausal sleep disturbances, the primary complaint that women report is waking up after they've first fallen asleep, waking up and then having trouble going back to sleep. So they're spending time in the night waking and then spending that time awake instead of sleeping, and what the NIRVANA trial shows is that with treatment with elinzanetant, there is this reduction in the amount of time spent awake. So when we look at the absolute numbers, whether it's 10 minutes or 18 minutes, it did differ depending on whether we were using our polysomnography, that was the in-lab gold standard sleep measurement, or using a device that's another objective measure of wakefulness, or of course looking at the self-report, like how long women thought they were spending awake, and it's on average around about a reduction of 10 minutes with elinzanetant, which is impactful.

So when you ask somebody who is spending a lot of time awake during the night, that is one of the main factors that influences how they feel the next day, so they will say they feel more tired. It also leads to a poor mood, sort of immediate impact the next day. So any improvement and reduction in the amount of how much time you're spending awake during the night is likely to have a benefit for the next day. I do think that there will be further results and further analysis of the data coming out from the NIRVANA trial that can very clearly look at the next-day impact and how that was improved with that reduction in wakefulness.

Contemporary OB/GYN:

These findings are post hoc and exploratory. How should that designation shape how providers communicate the sleep benefit of elinzanetant until more prospective sleep-focused data are available?

Baker:

I think that the NIRVANA trial adds to what we are already learning and know from the OASIS trials about the efficacy of elinzanetant in treating sleep disturbance associated with menopause, again, that is in women who have moderate-to-severe vasomotor symptoms, and so we're seeing that the evidence is building. NIRVANA adds to that by using these objective measures of wakefulness and sleep disturbance. Objective measures have a higher bar. As for the requirements for entry into the study, the women needed to have at least 30 minutes of objective measures of wakefulness based on polysomnography to enter the study, and so I think that the best way of looking at these results is putting it together with OASIS trials, that whether we are measuring self-reported sleep or measuring with our gold standard polysomnography, or measuring with a more modern device that's placed next to the bed and that's tracking objective sleep, we can see improvements in the elinzanetant compared to the placebo group.

That said, of course, there are more studies needed, because this was doing a post hoc analysis across the 12-week period, so we need to also look at women who not only have the moderate to severe vasomotor symptoms, but also consider women with a range of severity of vasomotor symptoms, and see how elinzanetant performs in those women.

I think the novelty about elinzanetant is that it's not hormonal. It is targeting the mechanism of hot flashes, and so it has a very targeted approach, and not only that, it has a dual action where it's hypothesized that the dual action of elinzanetant is not only targeting the mechanism of the hot flashes, but through its second mechanism may also be directly targeting the sleep disturbances associated with menopause. So, there's certainly a lot of evidence from mechanistic understandings, as well as from the NIRVANA and other trials, that elinzanetant is a promising option for women who have menopausal sleep disturbances, and right now in women who also have those moderate-to-severe vasomotor symptoms.

References:

1. Fitch J. Fiona Baker, PhD, details elinzanetant's effectiveness on wakefulness after sleep onset in postmenopausal women. Contemporary OB/GYN. Published June 16, 2026. Accessed June 18, 2026. https://www.contemporaryobgyn.net/view/fiona-baker-phd-details-elinzanetant-effectivenes-wakefulness-sleep-onset-postmenopausal
2. Joffe H, Soares Cl, Zammit G, et al. Effects of elinzanetant on wakefulness after sleep onset in postmenopausal women: Post hoc analysis of NIRVANA study. Abstract. Presented at: SLEEP 2026. June 14-17, 2026. Baltimore, Maryland.