Patient Medication Information: uses, side effects, how to take - Winrevair

What WINREVAIR® is used for:

WINREVAIR® is a prescription medicine to treat adults with pulmonary arterial hypertension (PAH). PAH is a type of high blood pressure in the arteries of your lungs.

How WINREVAIR® works:

WINREVAIR® is an activin receptor type IIA-Fc (ActRIIA-Fc) fusion protein which works to lower the blood pressure in the arteries of your lungs.

The ingredients in WINREVAIR® are:

Medicinal ingredient: sotatercept

Non-medicinal ingredients: citric acid monohydrate, polysorbate 80, sucrose, and tri-sodium citrate dihydrate at pH 5.8.

WINREVAIR® comes in the following dosage form:

Solution for injection: 45 mg or 60 mg for subcutaneous use.

Single-use vial (45 mg or 60 mg) is packaged in a kit. The kit contains the following components:

3 mL dosing syringe for administration
Needle for injection
Vial adapter(s)
Pre-filled syringe of sterile water for injection, necessary to reconstitute the lyophilized powder in the dose vial
Alcohol wipes

Do not use WINREVAIR® if:

You are allergic to sotatercept or to any of the other ingredients of WINREVAIR®.

To help avoid side effects and ensure proper use, talk to your healthcare professional before WINREVAIR® is administered. Talk about any health conditions or problems you may have, including if you:

Have or have had any medical conditions, and about any allergies.
Have symptoms of blood loss, easy bruising.

Other warnings you should know about:

Pregnancy

If you are pregnant, planning to get pregnant, become pregnant, or you think you may be pregnant while taking WINREVAIR® there are specific risks you must discuss with your healthcare professional. WINREVAIR® may harm your unborn baby.
Your healthcare professional should do a pregnancy test before you start taking WINREVAIR®.
You should use effective birth control when taking WINREVAIR®.
You should continue using effective birth control for at least 4 months after your last dose if you stop taking WINREVAIR®. Ask your healthcare professional about birth control methods that would work well for you.
You or your healthcare professional should report any exposure to WINREVAIR® during pregnancy by calling 1-800-567-2594.

Breastfeeding

It is not known if WINREVAIR® passes into breastmilk.
Do not breastfeed while taking WINREVAIR®.
Do not breastfeed for at least 4 months after your last dose if you stop taking WINREVAIR®. Talk to your healthcare professional about the best way to feed your baby.

Fertility

WINREVAIR® may decrease female and male fertility.

Children

It is not known if WINREVAIR® is safe and effective in children under 18 years of age. WINREVAIR® is not approved for use in children.

Tell your healthcare professional about all the medicines you take, including any drugs, vitamins, minerals, natural supplements or alternative medicines.

It is unknown if WINREVAIR® interacts with other medicines or supplements.

How to use WINREVAIR® (kit):

Read the separate Instructions for Use booklet that comes with your kit.

Use WINREVAIR® exactly as your healthcare professional tells you to.
You will use WINREVAIR® every 3 weeks as an injection just under your skin (subcutaneous) only in these injection sites:
- stomach (abdomen) at least 2 inches away from the belly button, or
- upper thigh
You should inject WINREVAIR® right away after mixing the medicine powder with the sterile water, but no later than 4 hours after mixing.

How you will receive WINREVAIR® (vial):

Your healthcare professional will give you WINREVAIR® every 3 weeks as an injection just under your skin (subcutaneous) only in these injection sites:
- stomach (abdomen) at least 2 inches away from the belly button, or
- upper thigh, or
- upper arm

Usual dose:

Your dose of WINREVAIR® depends on your body weight and blood tests.
Your healthcare professional will tell you how much WINREVAIR® to take and when to take it.
Do not change your dose or stop taking WINREVAIR® without talking to your healthcare professional.
Do not take WINREVAIR® more often than your healthcare professional tells you to. If you are not sure when to take WINREVAIR®, call your healthcare professional.

Your healthcare professional will monitor your dose:

Your healthcare professional will do a blood test before your first 5 doses of WINREVAIR®, longer if needed, and then from time to time to check your levels of hemoglobin (a protein in red blood cells that carries oxygen) and platelets (blood cells that help blood clot). After each of these blood tests, your healthcare provider may delay treatment or change your dose if needed.
Before your first dose and regularly while taking WINREVAIR®, your healthcare professional will do blood tests. These are done so that your healthcare professional can monitor you and find the best dose for you.
Your healthcare professional may adjust your dose, delay treatment, or stop treatment depending on how you respond to WINREVAIR®.

Overdose:

If you take too much WINREVAIR®, call your healthcare professional.

If you think you, or a person you are caring for, have taken too much WINREVAIR®, contact a healthcare professional, hospital emergency department, or regional poison control centre or Health Canada’s toll-free number, 1-844 POISON-X (1-844-764-7669) immediately, even if there are no symptoms.

Missed Dose (kit):

If you miss your prescribed dose of WINREVAIR®, take it within 3 days and follow your original schedule for your next dose. If not taken within 3 days, call your healthcare professional for guidance.

Missed Dose (vial):

If you miss your appointment to be given WINREVAIR®, call your healthcare professional immediately to reschedule your appointment.

Possible side effects from using WINREVAIR®:

These are not all the possible side effects you may have when taking WINREVAIR®. If you experience any side effects not listed here, tell your healthcare professional.

The most common side effects of WINREVAIR® are:

nose bleeds (epistaxis)
telangiectasia (also called spider veins or tiny blood vessels that look like pink or red lines on the skin)
headache
diarrhea
bleeding gums

The following additional side effect has been reported in general use with WINREVAIR®:

build-up of fluid around the heart (pericardial effusion)

Serious side effects and what to do about them

Frequency/Side Effect/Symptom	Talk to your healthcare professional	Stop taking drug and get immediate medical help
Only if severe		In all cases
Common
Serious bleeding: persistent headache, nausea, weakness, black or tarry stool, blood in your stool, bright red blood from vomiting or coughing, persistent abdominal cramps, severe back pain, or abnormally heavy menstrual bleeding, more likely to happen if you take WINREVAIR® with certain medicines. Your healthcare professional will inform you on how to recognize them.		✓
Rare
Erythrocytosis: high level of hemoglobin (a protein in red blood cells that carries oxygen): This can raise the chance of a blood clot forming that can block a blood vessel.		✓ Your healthcare professional will do blood tests to check your hemoglobin levels before starting and regularly during treatment with WINREVAIR®.
Severe Thrombocytopenia: low number of platelets (blood cells that help blood clot): easy bruising, continued bleeding from cuts, and nosebleeds.		✓ Your healthcare professional will do blood tests to check your platelet level before starting and regularly during treatment with WINREVAIR®.

If you have a troublesome symptom or side effect that is not listed here or becomes bad enough to interfere with your daily activities, tell your healthcare professional.

Reporting side effects

You can report any suspected side effects associated with the use of health products to Health Canada by:

Visiting the Web page on Adverse Reaction Reporting (https://www.canada.ca/en/health-canada/services/drugs-health-products/medeffect-canada/adverse-reaction-reporting.html) for information on how to report online, by mail or by fax; or
Calling toll-free at 1-866-234-2345.

NOTE: Contact your health professional if you need information about how to manage your side effects. The Canada Vigilance Program does not provide medical advice.

Storage:

Store WINREVAIR® in the refrigerator at 2°C to 8°C. Do not freeze.
Store in the original container to help protect from light.
Contact your healthcare professional if the unused injection kit has been out of the refrigerator for an extended period of time.
After you mix the medicine powder with the sterile water (provided in the kit), it is recommended that you inject it right away, but no later than 4 hours after mixing.

Keep out of reach and sight of children.

If you want more information about WINREVAIR®:

Talk to your healthcare professional.
Find the full product monograph that is prepared for healthcare professionals and includes the Patient Medication Information by visiting the Health Canada Drug Product Database website (https://www.canada.ca/en/health-canada/services/drugs-health-products/drug-products/drug-product-database.html); or the manufacturer’s website (www.merck.ca); or by calling 1-800-567-2594.

Date of Authorization: 2026-03-31

® Merck Sharp & Dohme B.V. Used under license.

Winrevair: Uses, Side Effects and Dosage