Winrevair (sotatercept or sotatercept-csrk) is an FDA-approved medication used to treat adults with pulmonary arterial hypertension (PAH). It’s an activin signaling inhibitor that helps increase your ability to exercise, improve your daily functioning, and decrease the chances of worsening PAH. Winrevair (sotatercept) is given as an injection under the skin every 3 weeks. It’s given by your PAH specialist at the beginning. But you can give the injection to yourself at home once you or a family member receives training from a healthcare professional. Common side effects include headaches, nose bleeds, and rashes.
In people with PAH, the walls of the small blood vessels in the lungs grow too thick. Scientists think that people with PAH may have extra activin, a protein that tells the blood vessels to get thicker, in their lungs.
When this happens, it makes the heart work harder to get blood to the lungs for oxygen. As a result, people with PAH have symptoms like shortness of breath, tiredness, dizziness, and chest pain.
Winrevair (sotatercept) is an activin signaling inhibitor, which means it blocks the activity of activin in the body. By balancing signals for blood vessel growth, Winrevair (sotatercept) prevents the blood vessels in the lungs from getting too thick.
Source: Prescribing information
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Only taken once every three weeks
Can inject at home once your PAH specialist knows how you react to the medication
Can use along with other medications for PAH
Must be given as an injection
Requires regular blood work to make sure your blood cell count is normal
Shouldn’t take while pregnant or breastfeeding
Winrevair (sotatercept) is given as an injection under the skin every 3 weeks by your PAH specialist. Eventually, your PAH specialist may train you or a family member to inject the medication at home. If this is the case, you’ll no longer need to come into the clinic to receive your injection.
Your PAH specialist will check your blood cell count before each of your first 5 doses and every so often during treatment. These blood tests help make sure Winrevair (sotatercept) is safe for you. Treatment raises the risk of having extra red blood cells, which can lead to blood clots. It can also put you at risk for having too few platelets, which can raise the risk for bleeding.
If you can get pregnant, make sure to use effective birth control while you’re taking Winrevair (sotatercept) and for at least 4 months after your last dose. This medication can be harmful to an unborn baby.
How to use Winrevair (sotatercept) at home:
Carefully review the instructions for use or watch the instructional video before you prepare and inject Winrevair (sotatercept) at home. If you have questions about how to use the medication, contact your PAH specialist or ask a pharmacist.
Each Winrevair (sotatercept) kit has everything you need for one dose. Don't save or reuse any of the materials in the kit for future use. Each kit is for a one-time use only.
Before you prepare Winrevair (sotatercept) for your injection, remove the kit from the refrigerator and wait 15 minutes for it to reach room temperature (injecting cold medication can be more uncomfortable). Don’t warm up Winrevair (sotatercept) in any other way, since that can damage the medication. As you wait, look at the vials and prefilled syringes to check for damage, leaks, or visible particles inside. If you find any damage, don’t use the kit and call the pharmacy to ask what to do next.
To prepare Winrevair (sotatercept), attach the prefilled syringe to the vial using the vial adapter. Then, slowly add all of the sterile water to the vial and swirl gently until the powder fully dissolves (don’t shake). Let the vial sit for 3 minutes to get rid of large bubbles. The solution should appear colorless to slightly brownish-yellow. Use the solution within 4 hours. If your kit contains 2 vials, repeat these steps with the second vial.
Follow your PAH specialist’s instructions to draw up your prescribed Winrevair (sotatercept) dose with the empty syringe and safety needle from the bottom tray. Remove any air bubbles or extra medication from the syringe, if needed.
To inject Winrevair (sotatercept), swab an area of skin on your belly or upper thigh with an alcohol wipe. Then, pinch the skin and insert the needle at a 45 to 90 degree (diagonal to vertical) angle. Slowly push the plunger all the way down to inject the medication.
Choose an area of skin to inject Winrevair (sotatercept) into that’s different from your most recent injection. Using different injection sites each time helps prevent skin irritation from repeated injections.
After each Winrevair (sotatercept) injection, put used needles, syringes, and anything else you used in a red sharps container to prevent injuries to yourself or others. Get rid of the sharps container as recommended in your area.
Winrevair (sotatercept) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Taking Winrevair (sotatercept) can raise the number of red blood cells in your body. Large increases in the number of red blood cells in your body can make you more likely to have a blood clot. It can also make your blood thicker so it doesn’t flow as freely.
Your PAH specialist will check your blood cell count before each Winrevair (sotatercept) injection for at least the first five doses. But they may continue to monitor your blood cell count from time to time during treatment. Based on your lab results, your PAH specialist will let you know whether you need to pause your Winrevair (sotatercept) injections.
Go to the emergency room right away if you experience symptoms of a blood clot, including redness or swelling of the legs, chest pain, difficulty breathing, or weakness of the face.
Risk factors: Low platelet levels | Also receiving prostacyclin therapy | Taking blood thinners
Taking Winrevair (sotatercept) can decrease the number of platelets you have in your body. Because platelets help your blood to clot, having low platelet levels makes you more likely to have serious bleeding.
Your PAH specialist will check your blood cell count before each of your first five doses of Winrevair (sotatercept). But they may continue to monitor your blood cell count every so often during treatment. If your platelet count is too low, your PAH specialist will decide whether you should hold off on your Winrevair dose to lessen your bleeding risk.
Watch out for signs of serious bleeding, such as blood in the urine, stool that appears black and sticky, vomit that looks like coffee grounds, or a bruise that keeps getting bigger. Go to the emergency room right away if you experience any of these symptoms. Additionally, go to the hospital if you fall and hit your head. Tell the care team that you fell so they know to check for any bleeding in the brain, even if you feel okay.
Studies in animals showed that Winrevair (sotatercept) can harm an unborn baby if it’s taken during pregnancy. If you’re able to get pregnant, it’s recommended that you take a pregnancy test before starting this medication. Also use effective birth control while taking Winrevair (sotatercept) and for at least four months after your last dose of the medication. If you think you may be pregnant or plan to become pregnant, talk to your PAH specialist or obstetrician-gynecologist (OB-GYN) about alternative treatment options.
Studies done in animals found that taking Winrevair (sotatercept) can make it more difficult to get pregnant or to get someone else pregnant. Animal studies showed that the change may be reversible after stopping the medication. Talk to your PAH specialist or OB-GYN about other medication options if you’re interested in having a baby while taking Winrevair (sotatercept).
In general, Winrevair (sotatercept) is injected under the skin every 3 weeks. Your PAH specialist will give injections into your belly, upper thigh, or upper arm. They can also train you to inject the medication on your own (under the skin of either your belly or upper thigh only).
Your dose will be based on your weight in kilograms (kg). The first dose is typically 0.3 mg/kg injected under the skin. Three weeks after that, the typical dose is 0.7 mg/kg injected under the skin every 3 weeks as a maintenance dose.
Note: Since Winrevair (sotatercept) is drawn up into a dosing syringe with milliliter (mL) markings, your PAH specialist will prescribe the medication using mL units.
Your PAH specialist may temporarily pause or adjust your dose depending on your blood test results and your risk for side effects.
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American Lung Association. (2024). Treating and managing PAH.
Hoeper, M. M., et al. (2023). Phase 3 trial of sotatercept for treatment of pulmonary arterial hypertension. The New England Journal of Medicine.
Merck & Co., Inc. (n.d.). Taking Winrevair™ (sotatercept-csrk).
Merck Sharp & Dohme LLC. (2024). Instructions for use: Winrevair™ (WIN-reh-vair) (sotatercept-csrk) for injection, for subcutaneous use.
Merck Sharp & Dohme LLC. (2024). Winrevair™ (sotatercept-csrk) for injection, for subcutaneous use [package insert].
Pulmonary Hypertension Association. (n.d.). Transplant and pulmonary hypertension.
Stubbe, B., et al. (2021). Intravenous prostacyclin-analogue therapy in pulmonary arterial hypertension – A review of the past, present and figure. Respiratory Medicine.
U.S. Food & Drug Administration. (2023). Best way to get rid of used needles and other sharps.
Upton, P. D., et al. (2022). An emerging class of new therapeutics targeting TGF, Activin, and BMP ligands in pulmonary arterial hypertension. Developmental Dynamics.
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