Idorsia reports dose-dependent sleep improvements with daridorexant in a pediatric Phase 2 insomnia study, supporting further clinical development.
Written By: Aasritha Thippavajjala, PharmD
Reviewed By: Pharmacally Editorial Team
Idorsia reported positive Phase 2 results for daridorexant in children and adolescents with insomnia disorder at the Sleep Europe 2026 congress. Announced on October 23, 2026, the findings showed a statistically significant dose-response relationship for objectively measured total sleep time (TST) after the first dose. At 50 mg, daridorexant increased sleep time by approximately 50 minutes from baseline, compared with 20 minutes with placebo.
Daridorexant is a dual orexin receptor antagonist (DORA) that targets orexin-mediated wake signalling. Although marketed as QUVIVIQ for adults in several markets, daridorexant remains investigational for pediatric use and is not approved or marketed for children in any country.
Study Design and Patient Population
The randomized, double-blind, placebo-controlled Phase 2 dose-finding study (NCT05423717) evaluated daridorexant at doses of 10 mg, 25 mg and 50 mg against placebo over two weeks. A total of 165 children and adolescents aged 10 to under 18 years with insomnia disorder received study treatment.
Participants included children without neurodevelopmental disorders, those with subthreshold autism spectrum disorder (ASD) or attention-deficit/hyperactivity disorder (ADHD) traits, and those with diagnosed neurodevelopmental disorders.
The primary endpoint was the change from baseline to Day 1 in TST measured by polysomnography (PSG), an objective method for assessing sleep duration. Additional assessments covered sleep initiation, sleep maintenance, sleep quality, morning sleepiness, alertness, daytime functioning, safety and tolerability.
Dose-Dependent Improvements in Total Sleep Time
The study met its primary endpoint, demonstrating a statistically significant dose-response relationship for TST on Day 1 (p=0.0185). A single 50 mg dose increased objectively measured TST by approximately 50 minutes from baseline, compared with 20 minutes with placebo.
The results were also notable in participants with neurodevelopmental disorders. In this subgroup, TST increased by approximately 64 minutes with daridorexant 50 mg, compared with 27 minutes with placebo. These findings suggest that orexin receptor antagonism warrants further investigation in children with insomnia and neurodevelopmental conditions, where treatment options remain limited.
However, the subgroup results should not be interpreted as proof that daridorexant is more effective in all children with ASD, ADHD or other neurodevelopmental disorders. The reported changes describe sleep-duration improvements from baseline, rather than direct evidence of improvements in underlying neurodevelopmental symptoms.
Caregiver-reported outcomes provided a complementary measure of benefit. After two weeks, reported TST increased by approximately 69 minutes from baseline with daridorexant 50 mg, compared with approximately 30 minutes with placebo. The 50 mg dose also produced the most consistent improvements across measures of sleep initiation, sleep maintenance and sleep quality, while morning sleepiness decreased numerically.
The distinction between these findings is important: the primary endpoint measured objective sleep duration after the first dose, whereas caregiver-reported sleep duration was assessed after two weeks.
Safety and Tolerability Findings
Daridorexant was reported to be well tolerated across the doses studied. At 50 mg, the highest recommended adult dose, the incidence of adverse events was similar to placebo, and the company reported no new safety findings relative to the established adult safety profile.
No adverse events suggestive of abuse potential or physical dependence, or withdrawal symptoms following treatment discontinuation, were reported during the study. These observations are encouraging but do not establish the absence of such risks during longer-term pediatric treatment.
The 14-day treatment period and relatively small study population limit conclusions about long-term safety, uncommon adverse events and sustained efficacy. Further studies will be needed to characterize the benefit-risk profile in children more fully.
Next Steps in Clinical Development
Idorsia said the manuscript describing the full study dataset was under evaluation by a scientific journal. The company was also consolidating feedback from global health authorities on the protocol for a pediatric Phase 3 development program, which it expects to initiate in the second half of 2027.
This remains a planned development milestone, not an initiated Phase 3 trial or a regulatory approval.
Clinical Interpretation
The Phase 2 findings provide early evidence that daridorexant can increase objectively measured sleep duration in children and adolescents with insomnia. The statistically significant dose-response relationship, supported by caregiver-reported outcomes and improvements across several sleep measures, provides a rationale for further clinical development.
The observed results in participants with neurodevelopmental disorders are particularly relevant, although the available findings do not establish superior efficacy in this subgroup or demonstrate improvements in associated neurodevelopmental symptoms. Similarly, short-term tolerability does not resolve questions about long-term pediatric safety.
The planned Phase 3 program will be important for confirming efficacy, evaluating durability of benefit and further characterizing safety. Until those data are available and regulatory requirements are met, daridorexant remains an investigational treatment for pediatric insomnia.
References
Idorsia Ltd. Idorsia presents outstanding results with daridorexant in children and adolescents with insomnia and an expanding body of evidence in adults at Sleep Europe 2026. October 23, 2026.
Dose-finding Study Assessing the Efficacy, Safety, and Pharmacokinetics of Daridorexant in Subjects Aged 10 to < 18 Years with Insomnia Disorder, ClinicalTrials.gov ID NCT05423717
About the Writer
Aasritha Thippavajjala (Linkedin) is a pharm D student and aspiring medical writer with medical writing, clinical training experience and a strong interest in clinical research and patient safety She has hands-on exposure to clinical pharmacy activities including medication profile assessment, clinical case review, identification of potential drug-related problems, ADR awareness, patient counselling, and clinical documentation. She has also gained experience in medical literature review, evidence synthesis, and scientific communication through her published review article on digital twin-based patient simulation and her poster presentation at the 74th Indian Pharmaceutical Congress. Certified in ICH Good Clinical Practice (E6(R3)) and Scientific Writing in Health Research, she is passionate about applying her clinical knowledge and research skills to medical writing ,clinical research and contributing to accurate, evidence-based healthcare.