Sotatercept-Csrk
Sotatercept-csrk (WINREVAIR) is a prescription injection used to treat pulmonary arterial hypertension (PAH) in adults, helping improve exercise ability, functional status, and reducing the risk of serious disease worsening.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
📖 Sotatercept-Csrk: Patient Information Guide
A plain-language walkthrough of Sotatercept-Csrk — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.
🎯What it's used for▾
Sotatercept-csrk is approved for use in adults with pulmonary arterial hypertension (PAH). All current FDA-supported uses are specific to WINREVAIR, the branded product.
- WINREVAIR is indicated for the treatment of adults with pulmonary arterial hypertension (PAH, WHO Group 1 pulmonary hypertension) to improve exercise capacity and WHO functional class
- WINREVAIR reduces the risk of clinical worsening events, including hospitalization for PAH, lung transplantation, and death
- WINREVAIR is used in combination with background standard-of-care PAH therapies, not as a standalone replacement
⚙️How it works▾
In pulmonary arterial hypertension, the small blood vessels in the lungs become abnormally narrow because cells in the vessel walls grow and multiply too much. WINREVAIR (sotatercept-csrk) is a fusion protein — a specially engineered molecule — that acts as a trap for activin A and related signaling proteins called TGF-β superfamily ligands. By binding these proteins, it quiets the pathway that drives excess cell growth and inflammation, and lets the opposing pathway that normally restrains vessel-wall thickening work properly again. In animal models, this led to thinner vessel walls, partial recovery of the right side of the heart, and better blood flow through the lungs.
💊How it's taken▾
WINREVAIR is given as a subcutaneous injection (a shot under the skin) once every three weeks. Treatment starts at a lower dose and is increased to the target dose over time, based on how your hemoglobin and platelet counts respond.
- Blood counts are checked before each of the first five doses — or longer if levels are not stable
- Doses may be delayed or reduced if hemoglobin rises too high or platelets fall too low
- There are no food restrictions associated with WINREVAIR
- Follow your prescriber's exact schedule — do not adjust your dose on your own
🤒Side effects — in detail▾
The most common side effects reported in clinical trials of WINREVAIR include:
- Nosebleeds (epistaxis)
- Headache
- Rash
- Telangiectasia (small, visible dilated blood vessels on the skin) — typically appearing after several months of treatment
- Diarrhea
- Dizziness
- Skin redness (erythema)
- Gum bleeding (gingival bleeding)
More serious reactions include a significant rise in red blood cell count (erythrocytosis), a dangerous drop in platelet count (severe thrombocytopenia), and serious bleeding events — contact your doctor right away if you notice signs of unusual bleeding, blood clots, or a very high blood pressure reading.
⚠️Warnings & precautions▾
- Erythrocytosis (too many red blood cells): WINREVAIR can raise hemoglobin levels. If levels get very high, the blood becomes too thick, raising the risk of blood clots and a condition called hyperviscosity syndrome. Regular blood monitoring is used to catch this early and adjust your dose if needed.
- Severe thrombocytopenia (very low platelets): WINREVAIR can lower platelet counts, which increases bleeding risk. Platelet counts are monitored closely, especially in the first several doses.
- Serious bleeding: Serious bleeding events have occurred, and the risk is higher in patients also taking prostacyclin therapies or blood thinners, or who have low platelet counts. WINREVAIR must not be given during active serious bleeding.
- Fetal harm (embryo-fetal toxicity): Animal studies show WINREVAIR can cause harm to a developing baby, including pregnancy loss and growth problems. Women who can become pregnant must use effective contraception during treatment and for at least 4 months after the last dose.
- Fertility: WINREVAIR may affect fertility in both women and men — discuss family planning with your doctor before starting treatment.
🔀What it interacts with▾
The FDA label for WINREVAIR identifies two key drug interaction concerns to discuss with your healthcare team:
- Prostacyclin therapies (medications commonly used to treat PAH, such as epoprostenol or treprostinil) — when combined with WINREVAIR, the risk of serious bleeding is increased
- Antithrombotic agents (blood thinners and antiplatelet drugs) — using these alongside WINREVAIR raises the risk of serious bleeding, especially if platelet counts are already low
This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.
📋Before taking it▾
- Pregnancy: WINREVAIR can harm a developing baby. A pregnancy test is recommended before starting, and effective contraception must be used during treatment and for at least 4 months after the final dose.
- Breastfeeding: Breastfeeding is not recommended during WINREVAIR treatment or for 4 months after the last dose, because the potential effects on an infant are unknown.
- Low platelet count: Treatment should not be started if your platelet count is below the safe threshold — your doctor will check this before your first dose.
- Fertility concerns: WINREVAIR may impair fertility in both men and women. Discuss this with your doctor before beginning treatment if having children is a consideration.
- Children: The safety and effectiveness of WINREVAIR have not been established in patients under 18 years of age.
- Older adults: Patients 65 and older were included in clinical studies without differences in effectiveness observed. Always share your complete health history with your prescriber.
- Kidney disease: No significant differences in drug behavior were seen in patients with mild to moderate kidney disease or end-stage kidney disease, but discuss your kidney health with your doctor.
🚑If you take too much▾
In studies of healthy volunteers, taking too much WINREVAIR caused hemoglobin to rise and blood pressure to increase; both improved with a procedure called phlebotomy (removing blood). If an overdose is suspected, medical monitoring of hemoglobin and blood pressure is recommended, along with supportive care. WINREVAIR cannot be removed from the body by dialysis.
📡Pharmacodynamics — effects in the body▾
In clinical trials, WINREVAIR significantly reduced pulmonary vascular resistance (PVR) — a measure of how hard the heart has to work to push blood through the lungs — compared to placebo. It also substantially lowered NT-proBNP, a blood marker of heart strain. In the highest-risk patients studied (ZENITH trial), WINREVAIR additionally reduced mean pulmonary artery pressure by a clinically meaningful amount. These changes reflect real improvements in how blood flows through the lungs and how much stress the heart is under.
🔬Pharmacokinetics — how your body processes it▾
WINREVAIR is given as a subcutaneous (under-the-skin) injection and reaches peak blood levels roughly 7 days after each dose, with about 66% of the drug absorbed into the bloodstream. It stays in the body for a long time — its effective half-life (the time it takes the body to clear half the drug) is approximately 24 days, so it takes about 15 weeks of regular dosing to reach stable, steady levels. The drug is broken down into small peptides by the body's normal protein-clearing pathways and is not significantly affected by age, sex, race, or kidney disease.
📦How to store it▾
Store vials refrigerated at 2°C to 8°C (36°F to 46°F) in original carton to protect from light. Do not freeze. refrigerator until ready for use.
📄 Written from Sotatercept-Csrk’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →
🩺 Pharmacist Counseling Corner
Quick, plain-English answers to the questions patients ask most about Sotatercept-Csrk — the kind of thing our pharmacy team would talk through with you at the counter.
What exactly is WINREVAIR and why has my doctor prescribed it? ▾
How is this medication given, and how often will I need it? ▾
What side effects should I watch out for? ▾
I'm a woman of childbearing age — what do I need to know? ▾
Why do I need so many blood tests while on this medication? ▾
How long does it take for WINREVAIR to start working? ▾
Is Sotatercept-Csrk available over the counter? ▾
When was Sotatercept-Csrk first available? ▾
Who makes Sotatercept-Csrk? ▾
💬 Answers drafted from Sotatercept-Csrk’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →
🧰 Keep exploring
💊 How Sotatercept-Csrk comes
Sotatercept-Csrk is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Injection
How this form is used
- WINREVAIR injection is used to treat adults with pulmonary arterial hypertension (PAH, WHO Group 1) to improve exercise capacity, improve WHO functional class, and reduce the risk of hospitalization, lung transplantation, or death related to PAH
- WINREVAIR is given as a subcutaneous (under the skin) injection once every three weeks
- WINREVAIR is started at a lower dose and increased to the target dose based on blood count monitoring and tolerability
- WINREVAIR should not be administered if the patient is experiencing serious active bleeding
- Hemoglobin and platelet counts must be checked before each of the first five doses of WINREVAIR, or longer if values are unstable, and periodically after that
Oral solution
📊 Sotatercept-Csrk across the U.S. market
How Sotatercept-Csrk appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
Also listed with the FDA, not a patient dose form: Kit (20) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
📈 How widely Sotatercept-Csrk is used
A general measure of how commonly Sotatercept-Csrk is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Sotatercept-Csrk is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Sotatercept-Csrk prescribed? Of the 1,596 medications we measure, Sotatercept-Csrk ranks #931 by Medicaid prescriptions — more than 42% of them.
Utilization by Sotatercept-Csrk product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
sotatercept-csrk 45 MG Injection Most dispensed
Summed across the 1 of 2 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2678937
sotatercept-csrk 60 MG Injection
Summed across the 1 of 2 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2678945
Other Sotatercept-Csrk products — combination packs and listings not yet matched to a specific clinical product (kept visible so every prescription is accounted for)
Summed across the 2 of 4 listed NDC products with Medicaid activity.
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Sotatercept-Csrk, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 4 of 8 listed Sotatercept-Csrk NDCs with Medicaid activity.
🔍 Compare Sotatercept-Csrk products
A representative set of FDA-listed product records for Sotatercept-Csrk — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|
| 💊Injection | |||
| 45 mg/mL | Patheon Italia S.p.A. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 60 mg/mL | Patheon Italia S.p.A. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 💊Oral solution | |||
| 1 g/g | AbbVie Inc. | BULK INGREDIENT | View NDC → |
| 1 kg/kg | SAMSUNG BIOLOGICS Co., Ltd. | BULK INGREDIENT | View NDC → |
| 💊Kits | |||
| — | Merck Sharp & Dohme LLC × 20 listings | BLA | View NDC → |
Showing 24 of 24 products — FDA National Drug Code Directory. See every product, package size and price: browse all 24 Sotatercept-Csrk NDCs →
📈 What people report — real-world data (FDA FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Sotatercept-Csrk — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Sotatercept-Csrk in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
🏛️ The road to your pharmacy
How Sotatercept-Csrk went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
🚨 Recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
Source: openFDA drug enforcement (recall) reports.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 2678930 1 dose form · 2 strengths
-
Dose form (SCDF) Injection RxCUI 2678934In current FDA listings
Look up RxCUI 2678930 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
📦 Supply & shortage status
Whether Sotatercept-Csrk is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
🏷️ Sold under these brand names
🏭 Manufacturers & labelers
RxNorm drug class
Sotatercept-Csrk belongs to the Activin Signaling Inhibitor class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
🔬 Where this comes from
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How we combine label and product data
HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.
For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Merck Sharp & Dohme LLC is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.
This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.