New results across pediatric, adult and real-world insomnia settings highlight the expanding clinical evidence for daridorexant at Sleep Europe 2026

Phase 2 results with daridorexant in pediatric insomnia disorder will be presented in a late-breaking "Impactful Clinical Trial" session. These are the first and only investigational data of a dual orexin receptor antagonist in children.

A growing body of real-world evidence will examine the use of daridorexant in routine clinical practice, including sleep outcomes, daytime functioning, quality of life and work productivity.

Further research will examine daridorexant in adults with insomnia and short sleep duration, and the evolving use of insomnia medications across six countries.

Investigator-initiated studies will explore daridorexant in menopausal women with insomnia and in patients with insomnia and epilepsy, major depressive disorder or sedative-hypnotic use disorder.

Allschwil, Switzerland – October 8, 2026
Idorsia Ltd (SIX: IDIA) continues its commitment to advancing the science of sleep and insomnia at Sleep Europe 2026, a leading European congress for sleep medicine and research, taking place in Maastricht, the Netherlands, from October 20 to 23, 2026. The scientific program features the first clinical study of a dual orexin receptor antagonist in pediatric insomnia disorder, new real-world evidence on daridorexant outcomes in routine practice, and analyses exploring the impact of dual orexin receptor antagonists on the treatment landscape of insomnia.

Late-breaking research in pediatric insomnia
Pediatric insomnia is associated with impaired sleep, daytime functioning, academic performance and quality of life, particularly in children with neurodevelopmental disorders such as Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD). Pharmacological treatment options for pediatric insomnia are very limited, with no approved medication in the US and only prolonged-release melatonin approved for certain pediatric populations in Europe.

The placebo-controlled, Phase 2, two-week dose-finding study evaluated daridorexant 10, 25 and 50 mg in children and adolescents aged 10 to under 18 years with insomnia disorder, including participants with neurodevelopmental disorders such as ASD and ADHD.

The study extends the scientific understanding of orexin signaling in insomnia to a younger and clinically complex population, particularly children and adolescents with neurodevelopmental disorders.

The detailed results were selected by the European Sleep Research Society (ESRS) for inclusion in the “Impactful Clinical Trial Session II” and will be presented by Professor Carmen M. Schröder. The findings will also be presented in a poster session later that day.

• Session II of “Impactful Clinical Trial”. Friday, October 23. Auditorium 2. 11:45-12:10 CEST

The dual orexin receptor antagonist daridorexant in pediatric insomnia disorder. Carmen Schröder, Akinyemi Ajayi, Oliviero Bruni, Yves Dauvilliers, Ingo Fietze, Katharina Lederer, Judith Owens, Adela Fraile, Fabio Pizza, Martine Clozel, Chiara De Stefani, Michael Meinel, Emanuele Noseda, Cedric Vaillant, Daniel Coury. Poster presentation. Friday, October 23. Poster Area 2, Level 1, F282

A growing body of real-world evidence for daridorexant
Two poster presentations will provide complementary perspectives from routine clinical practice, examining outcomes across the 24-hour burden of insomnia, from night-time symptoms to daytime functioning, quality of life and work productivity.

• Interim findings from the prospective ProDiGyA study in Germany and Austria will be presented on real-world treatment patterns, as well as changes in insomnia severity and depressive symptoms during the first months of daridorexant treatment:
  ProDiGyA: Interim Analysis of a Real-world, Prospective, Noninterventional Study Evaluating Daridorexant in Patients with Insomnia Disorder. Yaroslav Winter, Jens Kuhn, Göran Hajak, Stefan Ries, Corinna Frohn, Cornelius Bachman, Henry Memczak, Julia Kleylein-Sohn, Michael Saletu, Lucie Bartova. Wednesday, October 21. Poster Area 1, Level 1, W130
• Results of a Canadian noninterventional study will be presented on quality of life and work productivity in patients prescribed daridorexant:
  Effect of Daridorexant on Quality of Life and Work Productivity in Patients with Insomnia in a Canadian Real-World Setting. Wilfred Alonso, Julie Patenaude, Ariane Légaré, Marc Véronneau, Björn Steiniger-Brach, Jean Lachaine, Joseph Michaels. Wednesday, October 21. Poster Area 3, Level 0, W501

Further insights from the adult pivotal program
A new analysis of a pivotal adult Phase 3 study will examine the efficacy and safety of daridorexant in individuals with insomnia and objectively measured short sleep duration.

• Efficacy and Safety of Daridorexant in individuals with Insomnia with Short Sleep Duration. Julio Fernandez-Mendoza, Paul Saskin, Orestis Briasoulis, Joana Marques-Barros, Fjola Sigurdardottir, Yves Dauvilliers. Wednesday, October 21. Poster Area 3, Level 0, W500

How DORAs are changing the treatment landscape of insomnia
A six-country analysis will examine how the introduction of dual orexin receptor antagonists (DORAs) has influenced the use of traditional sedative-hypnotics, and how reimbursement and healthcare system policies have shaped their adoption.

• Impact of the Introduction of Dual Orexin Receptor Antagonists on the Usage of Prescription Medications for Insomnia. Dieter Kunz, Marco Di Nicola, Pierre-Alexis Geoffroy, Eddy Aelen, Francois Aerts, Björn Steiniger-Brach, Antonio Olivieri, David Taylor. Thursday, October 22. Poster Area 2, Level 1, T403

Investigator-Initiated research on daridorexant
At least six investigator-initiated studies of daridorexant will be presented at Sleep Europe 2026, reflecting continued scientific interest beyond the Idorsia-supported program. Together, these studies advance understanding of insomnia management, generate insights relevant to clinical practice, and help expand the scientific knowledge base on sleep and insomnia.
Presentations include the following investigator-initiated studies:

• Daridorexant for Chronic Insomnia in Menopausal Women: A Retrospective Real-World Study. Claudio Liguori
• Daridorexant in Adult People with Epilepsy and Chronic Insomnia: Preliminary Real-World Findings. Silvia Maio
• Daridorexant for chronic insomnia in patients with sedative-hypnotic use disorder and major depression: a comparative longitudinal study. Laura Palagini
• Hyperarousal Modulates Circadian Heart Rate Variations Associated to Daridorexant Treatment: An Explorative, Real-world, Observational Study. Alessandro Colitta
• Two Birds with One Stone: Efficacy of Daridorexant in Patients with MDD Comorbid with Insomnia. Meiyi Guo
• Daridorexant for Insomnia Disorder: outcomes across two years of treatment and post discontinuation findings. Laura Palagini

Additional investigator-initiated research and case reports involving daridorexant will also be presented. The full list of daridorexant-related presentations as well as their dates, times, and locations, is available online.

About Sleep Europe 2026
Sleep Europe 2026, the 28th Congress of the European Sleep Research Society, will take place in Maastricht, the Netherlands, from October 20 to 23, 2026. Held every two years, the congress brings together more than 3000 clinicians, researchers, scientists and other sleep professionals to share and discuss the latest advances in sleep medicine and sleep research.

Notes to the editor

About daridorexant – a different kind of insomnia treatment
Insomnia affects millions worldwide, yet commonly used treatments can lead to next day drowsiness, dependence, and withdrawal symptoms – leaving a clear unmet need for safer, effective alternatives.

Discovered by Idorsia, daridorexant works differently from traditional hypnotics. As a dual orexin receptor antagonist, it selectively targets the orexin system, helping to regulate overactive wake signaling without broadly suppressing brain activity. Its optimized pharmacokinetics promote restorative sleep throughout the entire night, reducing morning sleepiness and improving daytime functioning.

Clinical trials published in The Lancet Neurology demonstrated that daridorexant significantly improved sleep onset, sleep maintenance, and self-reported total sleep time in adult patients with insomnia at 25mg and 50mg doses compared to placebo. Daridorexant 50 mg also demonstrated a significant improvement in daytime functioning compared to placebo.

About Idorsia
The purpose of Idorsia is to discover, develop and commercialize innovative medicines to help more patients. To achieve this, we will develop Idorsia into a leading biopharmaceutical company, with a strong scientific core.

Headquartered near Basel, Switzerland – a European biotech hub – Idorsia has a highly experienced team of dedicated professionals, covering all disciplines from bench to bedside; QUVIVIQ™ (daridorexant), a different kind of insomnia treatment with the potential to revolutionize this mounting public health concern; strong partners to maximize the value of our portfolio; a promising in-house development pipeline; and a specialized drug discovery engine focused on small-molecule drugs that can change the treatment paradigm for many patients. Idorsia is listed on the SIX Swiss Exchange (ticker symbol: IDIA).

For further information, please contact:
Investor & Media Relations
Idorsia Pharmaceuticals Ltd, Hegenheimermattweg 91, CH-4123 Allschwil
+41 58 844 10 10
investor.relations@idorsia.com – media.relations@idorsia.com – www.idorsia.com

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