Pulmonary Arterial Hypertension
Overview

How Sotatercept Works

Instructions for Use Video

Safety Profile

Your healthcare professional should have directed you to this website for general education information about sotatercept. This information does not replace your healthcare professional’s advice.

Please always follow your healthcare professional’s instructions and talk with them about any questions or problems you have regarding your health and treatment.

All the information on this website is for adults, not children or adolescents. For information for children and adolescents, please consult with your healthcare professional for more information.

Indication

WINREVAIR® (sotatercept), in combination with other pulmonary arterial hypertension (PAH) therapies, is indicated for the treatment of PAH in adult patients with World Health Organization (WHO) Functional Class (FC) II to III, to improve exercise capacity.^1,2

What is Pulmonary Hypertension (PH)?³

PH is a rare condition that causes high blood pressure in the blood vessels connecting the heart and lungs (the pulmonary arteries).

PAH is a form of PH, which is defined as: ⁴

Pulmonary – means related to the lungs
Arterial – refers to the artery connecting the heart and lungs
Hypertension – means high blood pressure

In healthy pulmonary arteries, blood can flow easily within these vessels, transporting blood between the heart and lungs, as show in the diagram.

diagram showing the heart and lungs, showing the 4 steps of blood transport between the heart and lungs. Step 1: Blood returns to the heart after delivering oxygen to the body. Step 2: Blood gets pumped to the lungs via the pulmonary arteries to pick up a fresh supply of oxygen. Step 3: Blood returns to the heart from the lungs. Step 4: Oxygen-rich blood is pumped back out to the body.

diagram showing a human heart and lungs. The diagram also shows a through section of a healthy blood vessel, and a through section of a PAH-affected blood vessel

In patients with PAH, changes occur causing the pulmonary arteries to thicken and/or constrict, narrowing the space for blood to flow.

This can lead to symptoms such as shortness of breath, fatigue and chest tightness.³

How does Sotatercept work?

Sotatercept is the first and only activin signalling inhibitor indicated for PAH treatment.^1,2

In patients with PAH, signalling from excessive activins, a type of protein, leads to thickening of the artery walls.⁵

Sotatercept is designed to bind to activins, thereby reducing their signalling, and decrease excessive cell division, ultimately aiming to target a key cause of PAH progression.⁵

Watch the full mechanism of action video here:

Step-by-step self-administration video

Before administering Sotatercept, watch the self-administration video below and refer to the Instructions for Use Booklet.

Possible side effects⁶

Like all medicines, this medicine can cause side effects.

Talk to your doctor or pharmacist immediately if you notice:

Easy bruising, prolonged bleeding from cuts and nosebleeds. These could be signs of a low number of platelets (thrombocytopenia). This will be shown in your blood tests.

In addition, your doctor will do regular blood tests to notice whether you have:

High levels of haemoglobin

The serious side effects above may affect more than 1 in 10 people.

Talk to your doctor or pharmacist if you notice any of the following:

Very common (may affect more than 1 in 10 people)
Headache, Nosebleeds (epistaxis), Spider veins or tiny blood vessels that look like pink or red lines on the skin (telangiectasia), Diarrhoea, Dizziness, Skin rash

Common (may affect up to 1 in 10 people)
High blood pressure, Redness of the skin, Bleeding gums, Itching at the injection site

Additional warnings^1,2

Fertility: Based on findings in animals, Sotatercept may impair female and male fertility.

Children: The safety and efficacy of Sotatercept in children and adolescents below 18 years of age has not yet been established.

If you are pregnant or breast-feeding, think you may be pregnant, or are planning to have a baby, ask your doctor or pharmacist for advice before using this medicine.

Let your PH specialist team know about all medications you are currently taking, including any prescription drugs, vitamins, minerals, natural supplements, or alternative treatments. It is not known if Sotatercept interacts with other medications or supplements.

References

Sotatercept (45 mg) Summary of Product Characteristics. Available from: https://www.medicines.org.uk/emc/product/100843/smpc.
Sotatercept (60 mg) Summary of Product Characteristics. Available from: https://www.medicines.org.uk/emc/product/100844/smpc.
What is PH? PHA UK. Available at: https://www.phauk.org/about-ph-2/what-is-ph/.
Lan NS, et al. Diseases. 2018 May 16;6(2):38.
Humbert M, et al. N Engl J Med. 2021;384(13);1204-15.
Sotatercept. Patient Information Leaflet. 2025. Available from: https://www.medicines.org.uk/emc/product/100844/pil.

Merck Sharp & Dohme (UK) Limited Registered Office: 120 Moorgate, London, EC2M 6UR, United Kingdom.
Registered in England No. 233687 © 2025 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved.

GB-SOT-00019 | Date of Preparation: September 2025

Reporting of side effects: If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in the package leaflet. You can also report side effects directly via the Yellow Card Scheme at https://yellowcard.mhra.gov.uk/. By reporting side effects, you can help provide more information on the safety of this medicine.

Pulmonary Arterial Hypertension Overview