GNW-Adhoc: New data with daridorexant to be presented at SLEEP 2024

^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)

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