Patient info Open main menu

Mavacamten BMS 5 mg hard capsules – patient leaflet, side effects, dosage

Last updated: · Text from the MHRA, as of · About this document

Medicine status: Prescription only (POM) ▼ Additional monitoring Details

Medicine strength:
5 mg
Contains active substance:

Patient leaflet - Mavacamten BMS 5 mg hard capsules

1. What Mavacamten BMS is and what it is used for

What Mavacamten BMS is

Mavacamten BMS contains the active substance mavacamten. Mavacamten is a reversible cardiac myosin inhibitor, meaning that it changes the action of the muscle protein myosin in heart muscle cells. What Mavacamten BMS is used for

Mavacamten BMS is used to treat adults with a type of heart disease called obstructive hypertrophic cardiomyopathy (oHCM).

About obstructive hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a condition where the walls of the left heart chamber (ventricle) contract harder and become thicker than normal. As the walls thicken they can block (obstruct) the flow of blood out of the heart and can also make the heart stiff. This obstruction makes it more difficult for blood to flow into and out of the heart and be pumped to the body with each heartbeat, a condition known as obstructive hypertrophic cardiomyopathy (oHCM). Symptoms of oHCM are: chest pain and shortness of breath (especially with physical exercise); tiredness, abnormal heart rhythms, dizziness, feeling that you are about to faint, fainting (syncope) and swelling of the ankles, feet, legs, abdomen and/or veins in the neck. How Mavacamten BMS works

Mavacamten BMS works by reducing excess contraction of the heart and the obstruction to blood flow to the body. As a result, it may improve your symptoms and your ability to be active.

2. What you need to know before you take Mavacamten BMS

Do not take Mavacamten BMS if:

§ you are allergic to mavacamten or any of the

other ingredients of this medicine (listed in section 6).

§ you are pregnant or a woman of childbearing

potential not using effective contraception. § if you are taking medicines which may increase

the level of Mavacamten BMS in your blood such as:

  • oral medicines to treat fungal infections such

    as itraconazole, ketoconazole, posaconazole, voriconazole,

  • certain medicines to treat bacterial infections

    such as the antibiotics clarithromycin,

  • certain medicines to treat HIV infection such

    as cobicistat, ritonavir,

  • certain medicines to treat cancer such as

    ceritinib, idelalisib, tucatinib.

Ask your doctor if the medicine you are taking prevents you from taking mavacamten. See section “Other medicines and Mavacamten BMS” Warnings and precautions

Routine tests

Your doctor will assess how well your heart is working (your heart function) using an echocardiogram (an ultrasound test that takes images of your heart) before your first dose and regularly during treatment with Mavacamten BMS. It is very important to keep these echocardiogram appointments, because your doctor needs to check the effect of Mavacamten BMS on your heart. Your treatment dose may need to be adjusted to improve your response or to reduce side effects. If you are a woman who could become pregnant your doctor may perform a pregnancy test before starting treatment with Mavacamten BMS. Your doctor may do a test to check how this medicine is broken down (metabolised) in your body as this may be used to guide your Mavacamten BMS treatment (see section 3). Tell your doctor or pharmacist straight away:

§ if you get any of these symptoms during your treatment with Mavacamten BMS:

  • new or worsening shortness of breath, - chest pain,
  • tiredness,
  • palpitations (a forceful heartbeat that may be

    rapid or irregular), or

  • leg swelling.

These could be signs and symptoms of systolic dysfunction, a condition where the heart cannot pump with enough force, which can be life-threatening and lead to heart failure.

§ if you develop a serious infection or irregular

heart beat (arrhythmia) as this could increase your risk of developing heart failure. Your doctor may need to do additional tests of your heart function, interrupt the treatment or change your dose, depending on how you feel. Women of childbearing potential

If used during pregnancy, Mavacamten BMS can harm the unborn baby. Before you start treatment with Mavacamten BMS your doctor will explain the risk to you and ask you to do a pregnancy test in order to ensure that you are not pregnant. Your doctor will give you a card which explains why you should not become pregnant while taking Mavacamten BMS. It also explains what you should do to avoid becoming pregnant while you are taking Mavacamten BMS. You must use effective contraception during treatment and for 6 months after stopping treatment (see section “Pregnancy and breast-feeding”). If you do become pregnant while taking Mavacamten BMS, tell your doctor straight away. Your doctor will stop treatment (see “If you stop taking Mavacamten BMS” in section 3). Children and adolescents

Do not give this medicine to children (aged below 18 years) because the effectiveness and safety of Mavacamten BMS have not been studied in children and adolescents.

Other medicines and Mavacamten BMS

Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines. This is because some other medicines can affect the way Mavacamten BMS works. Some medicines can increase the amount of Mavacamten BMS in your body and make it more likely for you to get side effects that may be severe. Other medicines can reduce the amount of Mavacamten BMS in your body and may reduce its beneficial effects.

In particular, before taking Mavacamten BMS tell your doctor or pharmacist if you are taking, have recently taken, or have changed the dose of any of the following medicines:

§ some medicines used to reduce the amount

of acid your stomach produces (cimetidine, omeprazole, esomeprazole, pantoprazole) § antibiotics for bacterial infections (such as

clarithromycin, erythromycin)

§ medicines used to treat fungal infections (such

as itraconazole, fluconazole, ketoconazole, posaconazole and voriconazole)

§ medicines used to treat depression (such as

fluoxetine, fluvoxamine, citalopram) § medicines for HIV infections (such as ritonavir,

cobicistat, efavirenz)

§ rifampicin (an antibiotic for bacterial infections

like tuberculosis)

§ apalutamide, enzalutamide, mitotane, ceritinib,

idelalisib, ribociclib, tucatinib (medicines used to treat certain types of cancer)

§ medicines for fits (seizures) or epilepsy (such as

carbamazepine and phenytoin, phenobarbital, primidone)

§ St. John's wort (a herbal medicine for depression) § medicines that affect your heart (such as beta

blockers and calcium channel blockers e.g. verapamil and diltiazem)

§ medicines that make your heart more resistant

to abnormal activity (such as sodium channel blockers e.g. disopyramide)

§ ticlopidine (a medicine to prevent heart attack

and stroke)

§ letermovir (a medicine to treat cytomegalovirus

infections)

§ norethindrone (a medicine to treat various

menstrual problems)

§ prednisone (steroid).

If you take or have taken any of these medicines, or have changed the dose, your doctor needs to closely monitor you, may need to change your dose of Mavacamten BMS, or consider alternative treatments.

If you are not sure whether you are taking any of the medicines mentioned above, ask your doctor or pharmacist before taking Mavacamten BMS. Before stopping or changing the dose of a medicine or starting a new medicine, tell your doctor or pharmacist.

Do not take any of the above medicines occasionally or once in a while (not on a regular schedule) since that could change the amount of Mavacamten BMS in your body.

Mavacamten BMS with food and drink

You should use caution when drinking grapefruit juice while on treatment with Mavacamten BMS as it may change the amount of Mavacamten BMS in your body.

Pregnancy and breast-feeding

If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor for advice before taking this medicine.

Pregnancy

Do not take Mavacamten BMS during pregnancy, for 6 months before getting pregnant, or if you are a woman who could become pregnant and you are not using effective contraception. Mavacamten BMS may cause harm to your unborn baby. If you are a woman who could become pregnant, your doctor will inform you about this risk and will check if you are pregnant before starting treatment and regularly during treatment. Your doctor will give you a card which explains why you should not become pregnant while taking Mavacamten BMS. If you become pregnant, think you may be pregnant or planning to become pregnant while taking Mavacamten BMS, tell your doctor right away. Breast-feeding

It is not known if Mavacamten BMS passes through breastmilk. You must not breast-feed while taking Mavacamten BMS.

Driving and using machines

Mavacamten may have a small effect on your ability to drive and use machines. If you feel dizzy while taking this medicine, do not drive a vehicle, cycle or use any tools or machines.

Mavacamten BMS contains sodium

This medicinal product contains less than 1 mmol sodium (23 mg) per capsule, that is to say essentially ‘sodium-free’.

3. How to take Mavacamten BMS

Always take this medicine exactly as your doctor has told you. Check with your doctor if you are not sure. How much to take

The recommended starting dose is 2.5 mg or 5 mg taken by mouth once daily. Your doctor may do a test to check how this medicine is broken down (metabolised) in your body. The result may guide your Mavacamten BMS treatment. If you have liver problems, your doctor may also prescribe a reduced starting dose.

Your doctor will monitor how well your heart is working while you are taking Mavacamten BMS using echocardiograms and may change your dose (increase, lower, or temporarily stop) based on the results.

Your doctor will tell you how much Mavacamten BMS to take.

Your doctor will prescribe you a single daily dose of either 2.5 mg, 5 mg, 10 mg or 15 mg. The maximum single dose is 15 mg once daily. Always take Mavacamten BMS as prescribed by your doctor.

The first echocardiogram will be done before you start treatment, and then again during follow-up visits at week 4, 8 and 12 to assess your response to Mavacamten BMS. Routine echocardiograms will then be done every 3 months or 6 months. If your doctor changes your dose of Mavacamten BMS at any point, an echocardiogram will be done 4 weeks afterwards to make sure you are receiving a beneficial dose.

Taking this medicine

§ Swallow the capsule whole with a glass of water

at about the same time each day.

§ You can take the medicine with food or between

meals.

If you take more Mavacamten BMS than you should

If you take more capsules than you should, contact your doctor or go to a hospital straight away if you have taken 3 to 5 times the recommended dose. If possible, take the medicine pack and this leaflet with you.

If you forget to take Mavacamten BMS

If you forget to take Mavacamten BMS at the usual time, take your dose as soon as you remember on the same day and take your next dose at the usual time the next day. Do not take a double dose to make up for a forgotten capsule.

If you stop taking Mavacamten BMS

Do not stop taking Mavacamten BMS unless your doctor tells you to. If you wish to stop taking Mavacamten BMS, notify your doctor to discuss the best way to do so.

If you have any further questions on the use of this medicine, ask your doctor.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them. Serious side effects

Tell your doctor or pharmacist immediately if you get any of these symptoms during treatment with Mavacamten BMS:

§ new or worsening shortness of breath, chest pain, tiredness, palpitations (a forceful heartbeat that may be rapid or irregular), or leg swelling. These could be signs and symptoms of systolic dysfunction (a condition where the heart cannot pump with enough force), which can lead to heart failure and be life-threatening. (Common side effect)

Very common (may affect more than 1 in 10 people)

§ dizziness

§ difficulty breathing

Common (may affect up to 1 in 10 people)

§ fainting

Reporting of side effects

If you get any side effects, talk to your doctor. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the national reporting system (see details below). By reporting side effects you can help provide more information on the safety of this medicine. Yellow Card Scheme

Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store

5. How to store Mavacamten BMS

Keep this medicine out of the sight and reach of children.

Do not use this medicine after the expiry date which is stated on the blister and carton after EXP. The expiry date refers to the last day of that month. This medicine does not require any special storage conditions.

Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.

6. Contents of the pack and other information

What Mavacamten BMS contains

§ The active substance(s) is mavacamten. Each hard capsule contains either 2.5 mg, 5 mg, 10 mg or 15 mg of mavacamten.

§ The other ingredients are:

  • capsule content: silica, colloidal hydrated, mannitol (E421), hypromellose (E464), croscarmellose sodium (E468, see section 2 “Mavacamten BMS contains sodium”), magnesium stearate
  • capsule shell:

    Mavacamten BMS 2.5 mg hard capsules gelatin, titanium dioxide (E171), iron oxide black (E172), iron oxide red (E172) Mavacamten BMS 5 mg hard capsules gelatin, titanium dioxide (E171), iron oxide yellow (E172)

    Mavacamten BMS 10 mg hard capsules gelatin, titanium dioxide (E171), iron oxide red (E172)

    Mavacamten BMS 15 mg hard capsules gelatin, titanium dioxide (E171), iron oxide black (E172)

  • printing ink: iron oxide black (E172), shellac

    (E904), propylene glycol (E1520), ammonia solution, concentrated (E527), potassium hydroxide (E525).

What Mavacamten BMS looks like and contents of the pack

§ The Mavacamten BMS 2.5 mg, approximately

18.0 mm in length, hard capsules (capsules) have a light purple opaque cap and white opaque body imprinted in black ink with “2.5 mg” on the cap and “Mava” on the body. § The Mavacamten BMS 5 mg, approximately

18.0 mm in length, hard capsules (capsules) have a yellow opaque cap and white opaque body imprinted in black ink with “5 mg” on the cap and “Mava” on the body.

§ The Mavacamten BMS 10 mg, approximately

18.0 mm in length, hard capsules (capsules) have a pink opaque cap and white opaque body imprinted in black ink with “10 mg” on the cap and “Mava” on the body.

§ The Mavacamten BMS 15 mg, approximately

18.0 mm in length, hard capsules (capsules) have a grey opaque cap and white opaque body imprinted in black ink with “15 mg” on the cap and “Mava” on the body.

The hard capsules are packaged in aluminium foil blisters containing 14 hard capsules.

Each pack contains either 14 or 28 hard capsules. Not all pack sizes may be marketed.

Marketing Authorisation Holder

Bristol-Myers Squibb Pharma EEIG

Plaza 254

Blanchardstown Corporate Park 2

Dublin 15, D15 T867

Ireland

Manufacturer

Swords Laboratories Unlimited Company T/A Bristol-Myers Squibb Pharmaceutical Operations, External Manufacturing

Plaza 254

Blanchardstown Corporate Park 2

Dublin 15, D15 T867

Ireland

This leaflet was last revised in February 2026

SAP CODE

SAP CODE

Mavacamten BMS 2.5 mg Mavacamten BMS 5 mg

Mavacamten BMS 10 mg Mavacamten BMS 15 mg hard capsules

mavacamten

Mavacamten BMS 2.5 mg

Mavacamten BMS 5 mg

Mavacamten BMS 10 mg

Mavacamten BMS 15 mg

hard capsules

mavacamten

Approved 1.0v

About this document

Source: MHRA - Medicines and Healthcare products Regulatory Agency (products.mhra.gov.uk) · Marketing authorisation: PLGB 15105/0181

Last revision stated in the text: February 2026 · MHRA data as of 13 October 2026

Found a mistake? Tell us on the contact page.

The information on this site does not replace the advice of a doctor or pharmacist.

Facts about Mavacamten BMS 5 mg hard capsules

Prescription needed? Yes, prescription-only medicine (POM)
Active substance Mavacamten
Strength 5 mg
Pharmaceutical form Oral capsule
Mavacamten BMS 5 mg hard capsules
Yellow opaque cap imprinted with “5 mg” in black, and white opaque body imprinted with “Mava” in black, both in radial direction. Capsule size of approximately 18.0 mm in length.
How is it taken Oral
Excipients Silica, colloidal hydrated, Mannitol (E421), Hypromellose (E464), Croscarmellose sodium (E468), Magnesium stearate, Gelatin, Titanium dioxide (E171), Mavacamten BMS 5 mg hard capsules, Iron oxide yellow (E172), Iron oxide black (E172), Shellac (E904), Propylene glycol (E1520), Ammonia solution, concentrated (E527), Potassium hydroxide (E525)
Pack sizes 28 capsule
Is it available? Listed as available (NHS Dictionary of Medicines and Devices – not a record of current supplies)
Shelf life 3 years.
Storage This medicinal product does not require any special storage conditions.
Drug group (ATC) Cardiac therapy, Other cardiac preparations
Additional monitoring Yes ▼ – new safety information is collected quickly. Report any side effect to the Yellow Card scheme.
Marketing authorisation PLGB 15105/0181 (first authorised 28 July 2023)
Marketing authorisation holder Bristol-Myers Squibb Pharma EEIG
Codes GTIN 5012712800101

Sources: the MHRA product information (products.mhra.gov.uk) and the NHS Dictionary of Medicines and Devices (dm+d), release 10.2.0 of 19 October 2026, NHS Business Services Authority. Contains public sector information licensed under the Open Government Licence v3.0.