Aficamten
Aficamten (Myqorzo) is a cardiac myosin inhibitor used to treat adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM), a condition where the heart muscle is abnormally thick and blocks blood flow.
🧬 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 →
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾
Myqorzo can reduce the heart's pumping strength and cause heart failure. This happens because the drug lowers the left ventricular ejection fraction (LVEF) — a measure of how well your heart pumps blood out with each beat. Before you start Myqorzo and regularly while you take it, you must have echocardiograms (heart ultrasounds) to check this. Myqorzo should not be started if your LVEF is already too low. Watch for warning signs of heart failure: new or worsening shortness of breath, chest pain, unusual fatigue, or leg swelling. If any of these develop, contact your doctor right away.
📖 Aficamten: Patient Information Guide
A plain-language walkthrough of Aficamten — 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▾
Aficamten is approved as Myqorzo for one condition in adults:
- Myqorzo is indicated for the treatment of adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) — a condition where an abnormally thickened heart muscle creates an obstruction that limits blood flow out of the heart. Treatment aims to improve exercise tolerance and relieve symptoms such as shortness of breath and fatigue.
⚙️How it works▾
Aficamten is an allosteric and reversible cardiac myosin inhibitor. Cardiac myosin is the protein inside heart muscle cells that generates the force of each contraction. In oHCM, myosin is overactive — the heart muscle contracts too forcefully, causing it to thicken and creating a blockage (called left ventricular outflow tract obstruction, or LVOT obstruction) that restricts blood leaving the heart. Aficamten attaches to myosin at a site that modulates (rather than completely shuts off) its activity, reducing the force generated. This eases the obstruction and the excessive contraction that drive oHCM symptoms. Because the binding is reversible, the effects on heart function return to baseline within weeks after stopping the drug.
💊How it's taken▾
Myqorzo is taken as an oral tablet once daily, with or without food. The starting dose is low, and your prescriber will adjust it based on regular echocardiogram (heart ultrasound) results and how you feel — a process called titration. Do not change your dose or stop taking Myqorzo on your own; any adjustments must be guided by your care team. If you take other medications that interact with Myqorzo, your prescriber may start you at a specific dose or make adjustments when those medications are added or removed.
🤒Side effects — in detail▾
The most common side effect reported with Myqorzo in clinical trials was high blood pressure (hypertension), seen in about 8% of patients. Other effects to be aware of include:
- Reduced heart pumping strength (lower LVEF) — an expected, on-target effect that is monitored with echocardiograms
- Shortness of breath or worsening breathlessness
- Unusual fatigue
- Chest pain
- Leg swelling (edema)
Shortness of breath, chest pain, extreme fatigue, or leg swelling may signal heart failure — a serious complication. Contact your doctor right away if any of these develop or worsen.
⚠️Warnings & precautions▾
- Risk of heart failure: Myqorzo reduces the heart's pumping force, which can lower LVEF and lead to heart failure. This risk is higher during serious illnesses (such as severe infections) or if you develop a new arrhythmia like atrial fibrillation. Echocardiograms are required before and regularly during treatment. Signs to report immediately include shortness of breath, chest pain, fatigue, leg swelling, or sudden weight gain.
- Drug interactions leading to increased heart failure risk or reduced effectiveness: Certain medications can raise aficamten blood levels (increasing heart failure risk) or lower them (making Myqorzo less effective). Your prescriber must know every medication you take. Rifampin must never be used with Myqorzo.
- LVEF monitoring is non-negotiable: Myqorzo should not be started if LVEF is already too low, and treatment must be adjusted or interrupted if LVEF drops significantly during therapy.
🔀What it interacts with▾
Several medications can significantly affect how Myqorzo works in your body. Always tell your prescriber and pharmacist about everything you take:
- Rifampin (antibiotic for tuberculosis) — lowers aficamten levels so much that Myqorzo becomes ineffective; this combination is contraindicated (must not be used together)
- Fluvoxamine (used for OCD or depression) — raises aficamten levels, increasing the risk of heart failure; dose adjustment of Myqorzo is required
- Fluconazole and voriconazole (antifungal medications) — raise aficamten levels; depending on your current Myqorzo dose, your doctor may need to lower it or avoid the combination entirely
- Strong CYP2C9 inhibitors (a group of drugs that slow how your body breaks down aficamten) — can increase aficamten exposure and heart failure risk; Myqorzo dose reduction may be needed
- Moderate-to-strong CYP3A inducers (drugs that speed up the breakdown of aficamten, such as certain anticonvulsants) — can reduce Myqorzo's effectiveness; and stopping one of these inducers while on Myqorzo can abruptly raise aficamten levels and increase heart failure risk
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▾
- Rifampin use: Do not take Myqorzo if you take rifampin — this combination is contraindicated
- All other medications: Report every prescription, over-the-counter drug, supplement, and herbal product to your prescriber and pharmacist before starting Myqorzo
- Pregnancy: Myqorzo has caused fetal harm in animal studies. There are no adequate human pregnancy data. If you become pregnant while taking Myqorzo or within 3 weeks of your last dose, contact your healthcare provider and report the exposure to Cytokinetics at 1-833-633-2986
- Breastfeeding: It is not known whether aficamten passes into human breast milk. Discuss the risks and benefits with your doctor before breastfeeding while on Myqorzo
- Children: Myqorzo has not been studied in patients under 18; safety and effectiveness in pediatric patients have not been established
- Older adults (65+): Clinical trial data showed no overall difference in safety or effectiveness compared to younger adults, but regular monitoring remains essential
- Serious illness or arrhythmia: Tell your doctor right away if you develop a serious infection, new irregular heartbeat, or other significant illness while on Myqorzo — these conditions raise your risk of heart failure on this drug
🚑If you take too much▾
There have been no reported overdoses with Myqorzo. Based on how the drug works, taking too much could cause the heart to pump too weakly, leading to reduced LVEF, heart failure, or low blood pressure (hypotension). Signs to watch for include shortness of breath, extreme fatigue, leg swelling, or feeling faint. If an overdose is suspected, stop the medication, seek medical support to maintain stable circulation, and consider calling the Poison Help line at 1-800-222-1222.
📡Pharmacodynamics — effects in the body▾
In a large clinical trial (SEQUOIA-HCM), Myqorzo measurably reduced the pressure gradient (blockage) in the left ventricular outflow tract — the passage blood travels through as it leaves the heart — within 2 weeks of starting treatment, with continued improvement through 8 weeks and sustained effects over 24 weeks. As expected with its mechanism, Myqorzo also reduced LVEF (the percentage of blood pumped out with each beat) to a greater degree than placebo. Importantly, both the reduction in obstruction and the change in LVEF reversed within 4 weeks of stopping treatment, confirming the drug's effects are reversible. Myqorzo also reduced levels of NT-proBNP (a blood marker of heart stress) and troponin I (a marker of heart muscle strain), though the clinical significance of those specific findings is not yet fully established.
🔬Pharmacokinetics — how your body processes it▾
After taking Myqorzo by mouth, aficamten is rapidly absorbed, reaching peak blood levels in about 1.5 to 2 hours. Food does not meaningfully affect absorption. The drug builds up in the body with once-daily dosing, reaching steady (stable) levels after about 17 days. Aficamten has a long half-life of approximately 80 hours — meaning it stays in the body for several days after a dose, which contributes to its stable once-daily profile. It is broken down primarily by liver enzymes (mainly CYP2C9, with contributions from CYP3A, CYP2D6, and CYP2C19), which is why drugs that affect those enzymes can significantly alter aficamten levels in the blood.
📦How to store it▾
Store at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C to 30°C (59°F to 86°F) .
📄 Written from Aficamten’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 Aficamten — the kind of thing our pharmacy team would talk through with you at the counter.
What is Myqorzo actually doing for my heart condition? ▾
Why do I need echocardiograms so often while taking this medication? ▾
What side effects should I actually watch for at home? ▾
Are there medications I need to avoid while I'm on Myqorzo? ▾
Can I take Myqorzo if I'm pregnant or trying to get pregnant? ▾
What happens if I get sick with something unrelated — like a bad infection — while I'm on this medication? ▾
Is Aficamten available over the counter? ▾
When was Aficamten first available? ▾
💬 Answers drafted from Aficamten’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 Aficamten comes
Aficamten is available in 1 form. 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.
Tablet
How this form is used
- Myqorzo tablets are used to treat adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) to improve functional capacity and reduce symptoms
- Myqorzo is taken by mouth once daily
- Myqorzo tablets can be taken with or without food — a high-fat meal does not significantly affect absorption
- Myqorzo dosing is individualized based on echocardiogram results and your clinical status; do not adjust your dose without your prescriber's guidance
- Myqorzo requires echocardiogram assessments before starting and regularly during treatment to monitor heart function
📊 Aficamten across the U.S. market
How Aficamten 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.
🔍 Compare Aficamten products
A representative set of FDA-listed product records for Aficamten — 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 | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Tablet | ||||
| 5 mg | Oral | Cytokinetics Inc. | NDA | View NDC → |
| 10 mg | Oral | Cytokinetics Inc. | NDA | View NDC → |
| 15 mg | Oral | Cytokinetics Inc. | NDA | View NDC → |
| 20 mg | Oral | Cytokinetics Inc. | NDA | View NDC → |
Showing 4 of 4 products — FDA National Drug Code Directory. See every product, package size and price: browse all 4 Aficamten 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 Aficamten — 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 Aficamten 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 Aficamten 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 2731469 1 dose form · 4 strengths
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Dose form (SCDF) Oral Tablet RxCUI 2731473In current FDA listings
Look up RxCUI 2731469 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 Aficamten 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
🔬 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. Cytokinetics Inc. 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.