^Allschwil, Switzerland - June 3, 2024 Idorsia Ltd (SIX: IDIA) today announced that new data with daridorexant, Idorsia's dual orexin receptor antagonist for the treatment of adults with insomnia, will be presented at SLEEP 2024 - the 38(th) Annual Meeting of the Associated Professional Sleep Societies, taking place in Houston, Texas, from June 1- 5, 2024. Posters for daridorexant include the following: * Kaufmann P, et al. Excretion of the dual orexin receptor antagonist daridorexant into breast milk of healthy lactating women [0100] * Muehlan C, et al. Nighttime safety of daridorexant: response to noise stimuli, and effects on postural stability, walking and memory [0169] * McCall W, et al. Dose-response of daridorexant in insomnia disorder: a meta- analysis of phase 2 and 3 studies [0414] * Winter Y, et al. Real-world data and health-related quality of life in treatment of chronic insomnia with daridorexant [0415](*) The abstracts can be found in the SLEEP 2024 Abstract supplement (https://www.sleepmeeting.org/wp-content/uploads/2024/04/sleep-apss-annual- meeting-abstracts-2024.pdf). In addition to the poster presentations, Idorsia is hosting a commercial and medical booth (#211) and a product theater at SLEEP 2024. (*)This research is independent of Idorsia. Notes to the editor About daridorexant Daridorexant is Idorsia's dual orexin receptor antagonist (DORA) which blocks the binding of the wake-promoting orexin neuropeptides. Rather than inducing sleep through broad inhibition of brain activity, daridorexant only blocks the activation of orexin receptors. Daridorexant is commercially available as QUVIVIQ in the US, Germany, Italy, Switzerland, Spain, the UK, Canada, Austria, and France, and is approved throughout the EU. About Idorsia Idorsia Ltd is reaching out for more - We have more ideas, we see more opportunities and we want to help more patients. In order 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 is specialized in the discovery, development and commercialization of small molecules to transform the horizon of therapeutic options. Idorsia has a 25-year heritage of drug discovery, a broad portfolio of innovative drugs in the pipeline, an experienced team of professionals covering all disciplines from bench to bedside, and commercial operations in Europe and North America - the ideal constellation for bringing innovative medicines to patients. Idorsia was listed on the SIX Swiss Exchange (ticker symbol: IDIA) in June 2017 and has over 750 highly qualified specialists dedicated to realizing our ambitious targets. For further information, please contact Andrew C. Weiss Senior Vice President, Head of Investor Relations & Corporate Communications Idorsia Pharmaceuticals Ltd, Hegenheimermattweg 91, CH-4123 Allschwil +41 58 844 10 10 investor.relations@idorsia.com media.relations@idorsia.com www.idorsia.com (http://www.idorsia.com) The above information contains certain "forward-looking statements", relating to the company's business, which can be identified by the use of forward-looking terminology such as "estimates", "believes", "expects", "may", "are expected to", "will", "will continue", "should", "would be", "seeks", "pending" or "anticipates" or similar expressions, or by discussions of strategy, plans or intentions. Such statements include descriptions of the company's investment and research and development programs and anticipated expenditures in connection therewith, descriptions of new products expected to be introduced by the company and anticipated customer demand for such products and products in the company's existing portfolio. Such statements reflect the current views of the company with respect to future events and are subject to certain risks, uncertainties and assumptions. Many factors could cause the actual results, performance or achievements of the company to be materially different from any future results, performances or achievements that may be expressed or implied by such forward- looking statements. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described herein as anticipated, believed, estimated or expected. °

Quelle: dpa-Afx