Idorsia daridorexant Phase 2 paediatric data to headline Sleep Europe
Idorsia will present a substantial cluster of daridorexant data at Sleep Europe 2026, the biennial congress of the European Sleep Research Society (ESRS), taking place in Maastricht from 20 to 23 October. The programme spans five continents of evidence: a late-breaking paediatric Phase 2 study, new real-world datasets from Germany, Austria and Canada, an adult Phase 3 subgroup analysis, and at least six investigator-initiated studies exploring the drug in populations ranging from menopausal women to patients with epilepsy or major depressive disorder.
The centrepiece is a placebo-controlled, two-week dose-finding study evaluating daridorexant at 10 mg, 25 mg and 50 mg in children and adolescents aged 10 to under 18 years with insomnia disorder. The trial included participants with neurodevelopmental conditions such as autism spectrum disorder and attention-deficit/hyperactivity disorder. Idorsia describes it as the first and only clinical investigation of a dual orexin receptor antagonist (DORA) in paediatric insomnia, and the ESRS selected it for inclusion in its "Impactful Clinical Trial Session II". Professor Carmen Schröder will present the findings on 23 October.
Paediatric insomnia: an area with almost no approved options
The paediatric setting is notable for its near-total absence of approved pharmacotherapy. In the United States, no drug is approved for paediatric insomnia. In Europe, only prolonged-release melatonin holds approval for specific paediatric populations. That regulatory gap has limited treatment to off-label prescribing and behavioural interventions, leaving clinicians without a regulatory-endorsed pharmacological option, particularly for children with comorbid neurodevelopmental disorders in whom sleep disruption is both more common and more clinically disruptive.
Daridorexant's mechanism, selective blockade of both orexin-1 and orexin-2 receptors, is distinct from traditional sedative-hypnotics, which broadly suppress central nervous system activity. The DORA class has shown a cleaner side-effect profile in adults, with lower rates of next-day sedation and no established dependence liability at approved doses. Whether those properties translate to children is the scientific question the Phase 2 study is designed to begin answering; a two-week dose-finding design will not establish long-term safety or efficacy, and Idorsia has not disclosed plans or a timeline for a potential Phase 3 paediatric programme.
Real-world data and treatment landscape
Beyond the paediatric headline, real-world evidence from two non-interventional studies rounds out the congress presentation. Interim data from the ProDiGyA study in Germany and Austria will examine treatment patterns and changes in insomnia severity and depressive symptoms in routine practice. A Canadian study will look at quality-of-life and work-productivity outcomes in patients prescribed daridorexant, an endpoint set increasingly favoured by payers seeking to justify reimbursement of newer, more expensive sleep agents.
A six-country analysis adds a healthcare-economics lens, examining how the introduction of DORAs has affected prescription volumes for traditional sedative-hypnotics and how reimbursement policy has shaped adoption. This is a commercially relevant data point for Idorsia as it seeks to defend and extend market access for QUVIVIQ, its branded formulation of daridorexant, across European markets where pricing negotiations remain ongoing.
The investigator-initiated strand, which Idorsia notes is independent of its own sponsored programme, covers sedative-hypnotic use disorder, comorbid depression, epilepsy and menopausal insomnia. The breadth of conditions under active investigation suggests growing academic interest in the DORA class beyond the core adult chronic insomnia label. For Idorsia, which has faced balance-sheet pressure following the 2025 transfer of several pipeline assets to service debt obligations, demonstrating a widening evidence base for its lead commercial product carries strategic significance ahead of further partnering discussions.
Detailed results for all presentations will be available following the congress sessions. Idorsia has not indicated when data will be submitted for peer-reviewed publication.