^Idorsia will publish its Full Year 2023 and Q1 2024 Financial Reporting on

Tuesday May 21, 2024, at 07:00 CEST.

An investor conference call and webcast will be held to discuss the results on

the same day.

Date: Tuesday, May 21, 2024

Time: 14:00 CEST / 11:00 BST / 08:00 EDT

The call will start with presentations by senior management, followed by a Q&A

session.

Dial-in procedure:

1) Participants are required to register in advance of the conference

(link already open for registration) using the link provided below. Upon

registration, each participant will be provided with participant dial in

numbers, and a unique personal PIN.

2) In the 10 minutes prior to the call start time, participants will

need to use the conference access information provided in the e-mail received at

the point of registering. Participants may also use the Call Me feature instead

of dialing the nearest dial in number.

Online Registration:

https://register.vevent.com/register/BI431f6c4637014f91bccc3da0d59c1adc

Webcast: Participants should go to the Idorsia website www.idorsia.com

(http://www.idorsia.com) 10-15 minutes before the conference is due to start.

Replay: A replay of the investor webcast will be available through

www.idorsia.com (http://www.idorsia.com) approximately 60 minutes after the call

has ended.

Kind regards,

Andrew C. Weiss

Head of Investor Relations and Corporate Communications

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