^Ad hoc announcement pursuant to Art. 53 LR

* CEO, Jean-Paul Clozel, to update on how Idorsia is being adapted for

sustainable value creation

* The company is focused on extending the cash runway beyond the current

estimate of early April 2024, through various avenues, including potential

out-licensing deals

* Postponement of the publication of Full-Year 2023 Financial Results and the

subsequent Annual General Meeting of Shareholders

Allschwil, Switzerland - January 10, 2024

Idorsia Ltd (SIX: IDIA) today announced that Jean-Paul Clozel, Chief Executive

Officer of Idorsia, will present at the J.P. Morgan Healthcare Conference on

January 10, 2024, at 10:30 PST / 19:30 CET. The conference will take place at

the Westin St. Francis hotel in San Francisco, USA.

Jean-Paul will describe how Idorsia is being adapted for sustainable value

creation. The presentation will cover the progress of QUVIVIQ(TM) (daridorexant) in

the US and Europe, and the clinical data included in the new drug application

for aprocitentan with the US Food and Drug Administration (FDA) which is

currently under review. He will also present other unencumbered assets that

provide the company with strategic flexibility and several avenues to explore

potential fundraising. Follow this link

(https://jpmorgan.metameetings.net/events/healthcare24/sessions/49264-idorsia-

pharmaceuticals-ltd/webcast?gpu_only=true&kiosk=true) to access the audio stream

and find the presentation available here

(https://www.idorsia.com/dam/jcr:3b9c11d2-a3af-4914-935a-239588d0b046/2024-

idorsia-at-jpm-investor-webcast.pdf).

Jean-Paul Clozel MD and Chief Executive Officer of Idorsia commented:

"Creating a sustainable pharma company requires scientific innovation and

substantial investment. We have demonstrated our ability to innovate and bring

new drugs to the market and have a portfolio of innovative products, however, we

have limited financing, so we need to prioritize activities that offer the

maximum return in the near term. We estimate the current cash reserves to last

to early April 2024, we therefore plan to extend the cash runway through various

avenues, including potential out-license deals."

Expected highlights in 2024

* Secure additional funding to extend the cash runway

* Expand access and availability of QUVIVIQ (daridorexant) in the US, Canada

and across Europe

* Achieve FDA decision for the NDA for aprocitentan in resistant hypertension

* Achieve EMA decision for the MAA for aprocitentan in resistant hypertension

Jean-Paul commented on the portfolio:

"More than 11 million QUVIVIQ tablets have been dispensed to help patients

achieve better nights and days. We have made great progress with access and

availability in our key markets, and I expect to see that translating into

income in 2024. I also expect aprocitentan - the first antihypertensive working

on a new pathway for 30 years - to become available for treated patients whose

hypertension remains uncontrolled. Discussions with health authorities are going

well and I'm confident that the label will reflect the outstanding results we've

seen for these high-risk patients. We also intend to progress the two global

Phase 3 programs with selatogrel and cenerimod which have the potential to

transform treatment in their target indications."

Idorsia's portfolio

-------------------------------------------------------------------------------

Product / compound Mechanism of action Therapeutic area Status

-------------------------------------------------------------------------------

Commercially

available in the

US Germany,

Italy,

Switzerland,

Spain, the UK,

and Canada;

QUVIVIQ(TM) Dual orexin receptor Approved in the

(daridorexant) antagonist Insomnia EU; Phase 2 in

pediatric

insomnia -

recruiting

Partners: Mochida

& Sosei in Japan,

Simcere in China

and Hong Kong

-------------------------------------------------------------------------------

NDA under review

in the US,

MAA under review

Dual endothelin Resistant in the EU, other

Aprocitentan receptor antagonist hypertension filings in

preparation

Partner:

Unencumbered

-------------------------------------------------------------------------------

Phase 3 primary

endpoint not met;

Glucosylceramide open-label

Lucerastat synthase Fabry disease extension study

inhibitor ongoing

Partner:

Unencumbered

-------------------------------------------------------------------------------

Phase 3

Suspected acute recruiting

Selatogrel P2Y(12) inhibitor myocardial

infarction Partner:

Unencumbered

-------------------------------------------------------------------------------

Phase 3

S1P(1) receptor Systemic lupus recruiting

Cenerimod modulator erythematosus

Partner:

Unencumbered

-------------------------------------------------------------------------------

Multiple sclerosis Phase 2 in

ACKR3 / CXCR7 and other preparation

ACT-1004-1239 antagonist demyelinating

diseases Partner:

Unencumbered

-------------------------------------------------------------------------------

Rare lysosomal Phase 1 complete

Sinbaglustat GBA2/GCS inhibitor storage

disorders Partner:

Unencumbered

-------------------------------------------------------------------------------

Phase 1

ACT-1014-6470 C5aR1 antagonist Immune-mediated

disorders Partner:

Unencumbered

-------------------------------------------------------------------------------

Phase 1

ACT-777991 CXCR3 antagonist Recent-onset Type

1 diabetes Partner:

Unencumbered

-------------------------------------------------------------------------------

Phase 1

IDOR-1117-2520 Undisclosed Immune-mediated

disorders Partner:

Unencumbered

-------------------------------------------------------------------------------

Phase 1 in

Synthetic glycan Clostridium preparation

IDO-090 vaccine difficile

infection Partner:

Unencumbered

-------------------------------------------------------------------------------

Neurocrine Biosciences has a global license to develop and commercialize ACT-

709478 (NBI-827104), Idorsia's novel T-type calcium channel blocker.

On July 20, 2023, Idorsia sold its operating businesses in the Asia Pacific (ex-

China) region to Sosei Heptares, including the assignment of the license for

PIVLAZ (clazosentan) for the Asia Pacific (ex-China) region. Idorsia retains the

rights to clazosentan in the rest of the world.

Further details including the current status of each project in our portfolio

can be found in our innovation fact sheet

(https://www.idorsia.com/dam/jcr:ed5ae81e-28cc-4040-b984-f7b1be039bd1/fs-

innovation-portfolio.pdf).

Upcoming Financial Updates

The company has decided to postpone the publication of Full-Year 2023 Financial

Results and the subsequent Annual General Meeting of Shareholders.

* Full-Year 2023 and First Quarter 2024 Financial Results reporting on April

25, 2024

* Annual General Meeting of Shareholders on June 13, 2024

* Half-Year 2024 Financial Results reporting on July 25, 2024

Notes to the editor

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 20-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 800 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 (mailto:investor.relations@idorsia.com)

media.relations@idorsia.com (mailto: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.

°