What it is
Seltorexant, also known as JNJ-42847922 or MIN-202, is an investigational selective orexin-2 receptor antagonist. Orexin is part of the brain's wake-maintenance system. The basic idea is to reduce an arousal signal that keeps wakefulness active rather than create sleep through a broad sedative mechanism.
Why the selective mechanism caught my attention
The practical target was not simply feeling knocked out. It was quieter sleep: falling asleep cleanly, waking less during the night, and returning to sleep without carrying an obvious next-morning penalty. Seltorexant was designed to favor the orexin-2 receptor and has a relatively short human half-life of roughly two to three hours, making sleep continuity and next-morning alertness the useful real-world questions.
The strongest insomnia trial
A randomized, double-blind trial enrolled 364 adults with insomnia and compared 5 mg, 10 mg, and 20 mg of Seltorexant with placebo and zolpidem. The clearest effects appeared at 10 mg and 20 mg: participants fell asleep faster and spent less time awake after sleep onset, and those effects remained present with repeated treatment. The study's conclusion did not establish 5 mg as an efficacious insomnia dose.
The earlier sleep-efficiency signal
An earlier crossover study used 40 mg in 27 people with insomnia. Compared with placebo, Seltorexant increased total sleep by about 28 minutes after the first dose and 38 minutes after repeated dosing. Sleep efficiency improved by 5.8 and 7.9 percentage points, respectively. Sleep onset also became faster, while wake time after sleep onset fell by roughly 11 minutes.
Evidence in persistent insomnia with depression
A separate four-way crossover study in 20 antidepressant-treated people with persistent insomnia tested single doses of 10 mg, 20 mg, and 40 mg. All three amounts shortened sleep latency, increased total sleep, and improved sleep efficiency compared with placebo. That population is different from mine, but it reinforces the same expected signature: faster onset and better sleep maintenance.
Timing and residual-effect context
In a healthy-volunteer study spanning 5–60 mg, Seltorexant reached peak concentration in approximately 0.5–1.5 hours and had a mean half-life of two to three hours. Amounts above 5 mg registered as sedating four hours after daytime administration, while 20 mg and above consistently produced somnolence. The short profile is relevant to next-morning function, but it does not guarantee an absence of residual effects.
Safety and development status
Seltorexant remains investigational. Johnson & Johnson's current pipeline lists it in phase 3 for adjunctive treatment of major depressive disorder with insomnia symptoms. In the 364-person insomnia trial, most treatment-emergent adverse events were mild or moderate; headache was the most common, and somnolence was more frequent at 20 mg than at 5 or 10 mg. Uncommon rhythm or conduction findings also led several participants to discontinue treatment.
Sources
- Mesens et al., JAMA Psychiatry 2025 — 364-person randomized insomnia trial comparing 5 mg, 10 mg, 20 mg, placebo, and zolpidem.
- De Boer et al., Journal of Psychopharmacology 2018 — 40 mg crossover trial measuring sleep efficiency, total sleep, sleep latency, and wake after sleep onset.
- Brooks et al., Journal of Psychopharmacology 2019 — 10 mg, 20 mg, and 40 mg crossover study in persistent insomnia with major depressive disorder.
- Van der Ark et al., Journal of Psychopharmacology 2018 — repeated-dose human pharmacokinetics, somnolence, alertness, and tolerability study.
- Bonaventure et al., Journal of Pharmacology and Experimental Therapeutics 2015 — orexin-2 selectivity, target engagement, preclinical sleep effects, and early clinical-candidate characterization.
- Johnson & Johnson development pipeline — current investigational and phase 3 development status.