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, III, and IV. 1,2
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
This makes it easier for the heart to pump blood to the lungs and slows down the progression of disease. It can relieve PAH symptoms, help patients live longer and lower the need for a lung transplant or hospitalisation for PAH. 6
A simplified image of a sotatercept molecule
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, Bleeding gums, Back pain
-
Common (may affect up to 1 in 10 people)
High blood pressure, Redness of the skin, An infection in the urinary tract (kidney, bladder or urethra) that may cause lower back or belly pain and burning during urination, Itching at the injection site -
Uncommon (may affect up to 1 in 100 people):
Intrapulmonary shunting (a condition where blood bypasses the normal route through the lungs that can result in less oxygen delivery to the body)
Additional warnings1,2
Fertility: Based on findings in animals, sotatercept may impair female and male fertility.
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.
Children: The safety and efficacy of sotatercept in children and adolescents below 18 years of age has not yet been established.
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. 2026. 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 © 2026 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved.
GB-SOT-00165 | Date of Preparation: June 2026
Page last reviewed: June 2026 | Next review due: June 2028
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.
