^Ad hoc announcement pursuant to Art. 53 LR

* Viatris and Idorsia will collaborate on the global development and

commercialization of two Phase 3 assets, selatogrel and cenerimod.

* Idorsia to receive an upfront payment of USD 350 million, potential

development and regulatory milestone payments, additional sales milestone

payments and tiered royalties on annual net sales.

* Viatris and Idorsia will both contribute to the development costs for both

programs.

* Includes future optionality to expand collaboration with additional pipeline

assets.

* Combines Viatris' financial strength and worldwide operational

infrastructure with Idorsia's proven, highly productive drug development

team and innovative engine.

Allschwil, Switzerland - February 28, 2024

Idorsia Ltd (SIX: IDIA) today announced that it has entered into agreements for

a significant global research and development collaboration with Viatris Inc.

(NASDAQ: VTRS), a global healthcare company, for the global development and

commercialization of two Phase 3 assets - selatogrel and cenerimod - for an

upfront payment of USD 350 million, potential development and regulatory

milestone payments, and certain contingent payments of additional sales

milestone payments and tiered royalties from mid-single- to low double-digit

percentage on annual net sales.

A joint development committee will oversee the development of the ongoing Phase

3 programs for selatogrel and cenerimod through regulatory approval. Idorsia

will contribute up to USD 200 million in the next 3 years and will transfer to

Viatris at closing the dedicated personnel to both programs.

Viatris will have worldwide commercialization rights for both selatogrel and

cenerimod (excluding, for cenerimod only, Japan, South Korea and certain

countries in the Asia-Pacific region).

Idorsia has also granted Viatris a Right of First Refusal and First Negotiation

for certain other pipeline assets.

The company expects to close the transaction by the end of March, subject to

customary closing conditions, but no additional regulatory or shareholder

approvals are required.

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

"I'm delighted that with Viatris we have found a strong partner to secure and

accelerate the development programs for both selatogrel and cenerimod by

leveraging the strength of Viatris' global infrastructure. From the first

meeting, it was clear that the team at Viatris shares the same excitement and

engagement for our innovations. This global collaboration allows us to share the

costs of the ongoing Phase 3 programs whilst retaining long-term shareholder

value, by sharing the rewards for success through the milestones and royalties."

Scott A. Smith, Chief Executive Officer of Viatris, commented:

"I am extremely pleased with our global research and development collaboration

with Idorsia. We are connecting Idorsia's proven, highly productive drug

development team and innovation engine with Viatris' strong global

infrastructure and experience to focus on two late-stage potential blockbuster

assets with long-dated patent protection. I believe that together we will be

able to execute on the potential of these global assets and any future assets as

we work to deliver on our goal of building a more durable, predictable portfolio

on the foundation of our strong base business, and that selatogrel and cenerimod

can become meaningful components of Viatris' business over the long term."

André C. Muller, Chief Financial Officer of Idorsia, commented:

"In the coming weeks and months, we have many inflection points ahead, namely

the FDA and CHMP decisions for aprocitentan, as well as expanded access and

availability of QUVIVIQ (daridorexant) in the US, Canada and across Europe."

André continued:

"The upfront payment of USD 350 million gives us much needed liquidity. We've

repeatedly explained that we have many balls in the air, we've now caught the

first one and continue to work on others to secure Idorsia's future. We are

working on several funding options, including business development

opportunities, equity, and equity-linked deals to significantly extend our cash

runway."

Notes to the editor

About selatogrel

Selatogrel is a potent, fast-acting, reversible, and highly selective

P2Y(12) inhibitor, being developed for the treatment of acute myocardial

infarction (AMI), in patients with a history of AMI. It is intended to be self-

administered subcutaneously via a drug delivery system (autoinjector). This

novel, self-administered emergency agent has the potential to protect heart

muscle in the very early phase of an AMI - in the crucial time between symptom

onset and first medical attention - so as to treat the ongoing AMI and prevent

early death.

Idorsia is enrolling patients into a large international, double-blind,

randomized, placebo-controlled Phase 3 study - Selatogrel Outcome Study in

suspected Acute Myocardial Infarction (SOS-AMI) - to assess the clinical

efficacy and safety of selatogrel 16 mg when self administered (on top of

standard of care) upon the occurrence of symptoms suggestive of AMI. The primary

efficacy endpoint is the occurrence of death from any cause, or non-fatal AMI,

after self-administration of the study treatment.

A Special Protocol Assessment has been agreed with the FDA, indicating its

concurrence with the adequacy and acceptability of critical elements of overall

protocol design for a study intended to support a future marketing application.

In addition, the FDA designated the investigation of selatogrel for the

treatment of suspected AMI as a "fast-track" development program. This

designation is intended to promote communication and collaboration between the

FDA and pharmaceutical companies for drugs that treat serious conditions and

fill an unmet medical need.

About cenerimod

Cenerimod, the result of 20 years of research in Idorsia's labs, is a highly

selective S1P(1) receptor modulator, given as an oral once-daily tablet.

Cenerimod potentially offers a novel approach for the treatment of systemic

lupus erythematosus (SLE), a disease with a significant impact on patients and

limited treatment options.

In December 2022, Idorsia initiated the OPUS program (Oral S1P(1) Receptor

ModUlation in SLE), which consists of two multicenter, randomized, double-blind,

placebo-controlled, parallel-group Phase 3 studies to evaluate the efficacy,

safety, and tolerability of cenerimod in adult patients with moderate to severe

SLE on top of background therapy. The main objectives of the program are to

evaluate the effectiveness of cenerimod 4 mg in reducing disease activity, as

well as controlling the disease, compared to placebo. The primary endpoint is

response on SRI-4 at month 12 compared to baseline. Secondary endpoints include

response on BICLA at month 12 compard to baseline and - for the first time in a

lupus registration study - measures of sustained disease control: time to first

confirmed 4-month sustained mSLEDAI-2K response and time to first confirmed 4-

month sustained response in mucocutaneous manifestations (i.e. rash, alopecia,

mucosal ulcers).

The investigation of cenerimod for the treatment of SLE has been designated as a

"fast-track" development program by the FDA. This designation is intended to

promote communication and collaboration between the FDA and pharmaceutical

companies for drugs that treat serious conditions and fill an unmet medical

need.

About Viatris

Viatris Inc. (NASDAQ: VTRS) is a global healthcare company uniquely positioned

to bridge the traditional divide between generics and brands, combining the best

of both to more holistically address healthcare needs globally. With a mission

to empower people worldwide to live healthier at every stage of life, we provide

access at scale, currently supplying high-quality medicines to approximately 1

billion patients around the world annually and touching all of life's moments,

from birth to the end of life, acute conditions to chronic diseases. With our

exceptionally extensive and diverse portfolio of medicines, a one-of-a-kind

global supply chain designed to reach more people when and where they need them,

and the scientific expertise to address some of the world's most enduring health

challenges, access takes on deep meaning at Viatris. We are headquartered in the

U.S., with global centers in Pittsburgh, Shanghai and Hyderabad, India. Learn

more at viatris.com and investor.viatris.com, and connect with us on LinkedIn,

Instagram, YouTube and X (formerly Twitter).

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)

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materialize, or should underlying assumptions prove incorrect, actual results

may vary materially from those described herein as anticipated, believed,

estimated or expected.

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