Hypertrophic cardiomyopathy is a heart condition where the heart muscle becomes abnormally thick. This makes it harder for the heart to work correctly. Obstructive hypertrophic cardiomyopathy (oHCM) is the most common type of HCM. It happens when the thickened heart muscle blocks blood from flowing out of the heart. The obstruction makes the heart work harder, leading to symptoms that get worse over time.
Camzyos was the first medicine specifically made to target the main cause of obstructive HCM. For people with symptoms, Camzyos may help improve symptoms and improve physical activity.
How Your Medicine Works
Your heart is a strong muscle that pumps blood throughout your body. In a healthy heart, there are millions of tiny protein fibers (myosin and actin) working together to squeeze (contract) and relax the heart muscle.
In oHCM, there is increased myosin activity, which causes the heart muscle to contract with more force and have difficulty relaxing. The heart muscle gets thick and stiff. This can make it hard for the heart to fill up with blood. It can also make it tough for the heart to push blood out to the body. All of this can lead to heart failure, heart rhythm changes like atrial fibrillation, and a stroke or thromboembolism. Symptoms of oHCM worsen over time and can lead you to limit your daily activities. (See table for symptoms)
| Example of oHCM Symptoms | |
|
|
Until the approval of Camzyos, health care providers managed symptoms of HCM, recommended lifestyle changes for diet and exercise, and suggested surgery for severe symptoms. Now, there are new medicines that target the excess myosin activity.
Camzyos reduces the myosin activity in the heart to help balance the contraction and relaxation of the muscle. This allows the heart to fill with blood and pump it out efficiently. Over time, Camzyos may reduce the obstruction, improve symptoms, and increase physical activity.
How Should I Take This Medicine?
Camzyos is a capsule taken at the same time once a day. The capsule is swallowed whole. Do not crush, chew, or sprinkle Camzyos on food.
You will start at a beginning dose, and your health care provider will tell you when and how to increase the dose. Your dose may be changed or stopped by your health care provider if you have an illness (like a serious infection), you are on a specific medicine, or you have heart rhythm changes. It is important to take it as prescribed by your health care provider.
What Studies Were Completed?
Two studies were done to look at the safety and efficacy of Camzyos in people with oHCM, compared with a placebo (a dummy medicine that has no effect). Placebo-controlled studies help researchers see differences in benefit or harm of a medicine when compared with no treatment.
Study 1
People in the study took Camzyos or a placebo for 30 weeks and then were monitored for 8 weeks without any treatment. All people in the study had oHCM, with moderate heart failure symptoms (Class II and III) and severe obstruction. People in the study were at least 18 years old, with an average age of 59 years. About 90% of the people in the study identified as White, with about 10% identifying as Black or African American, Asian, Native American, Alaska Native, or unknown.
Efficacy was measured by assessing blood flow, reviewing symptoms, collecting patient-reported outcomes, and testing the ability to exercise. (See table)
| Blood flow | Left ventricular outflow tract (LVOT) gradient – difference between blood flow pressures in the heart and leaving the heart
|
|
| Symptoms | New York Heart Association (NYHA) Class
|
|
| Patient-reported outcomes | Kansas City Cardiomyopathy Questionnaire – Clinical Summary Score (KCCQ-CSS or KCCQ-23-CSS )
Hypertrophic Cardiomyopathy Symptom Questionnaire – Shortness of Breath (HCMSQ-SoB) Score
|
|
| Ability to Exercise |
|
|
The primary clinical response was defined as improvements when combining at least one of the following changes in exercise capacity (pVO2) and/or improvement in symptoms (NYHA Class changes).
- pVO2 improvement by at least 1.5 mL/kg/min and at least 1 improvement in NYHA Class
- pVO2 improvement by at least 3.0 mL/kg/min and no worsening in NYHA Class
Other efficacy measures included individual changes in the measurements described in the table.
Study 2
This study was done to see if Camzyos was effective in preventing or delaying the need for surgery after 16 weeks of Camzyos or a placebo. All patients had oHCM, had maxed out on all medical therapy, were being referred for surgery called septal reduction therapy (SRT), and had an LVOT gradient ≥ 50 mmHg. People in the study were at least 18 years old, with an average age of 60 years. About 90% of the people in the study identified as White, with the other 10% identifying as Black, Asian, or unspecified/other.
SRT is a surgery that is typically done when someone has severe symptoms despite other medicines and lifestyle changes. Patients are referred for SRT when they have NYHA Class II (with exercise-induced symptoms) or Class III/IV and an LVOT gradient of ≥ 50 mmHg. SRT carries its own risks, since it is an invasive procedure, so the goal of this study was to see if Camzyos could help reduce symptoms without the risk of surgery.
The main efficacy endpoint was the number of people in the study who were still eligible for the SRT procedure at the end of 16 weeks or decided to move forward with SRT before the end of the study. Other efficacy measures included individual changes in the following measurements described in the Table above.
- LVOT gradient
- NYHA Class
- KCCQ-23-CSS questionnaire scores
What Benefits Were Seen in the Studies?
In Study 1, Camzyos reduced the obstruction of blood flow and improved symptoms. People taking Camzyos reported that their quality of life was improved, and they were able to do more daily activities, compared to the people taking the placebo. Twice as many people taking Camzyos (37%) reached the combined outcome, compared to people taking the placebo (17%). This means that more people taking Camzyos were able to do more physical activity and reported fewer symptoms.
LVOT gradient. LVOT gradients were about four times lower in people taking Camzyos, compared with people taking the placebo. After exercise, the average decrease in LVOT gradient was 47 mmHg for people taking Camzyos, compared with 10 mmHg for people taking the placebo. This means that the obstruction of blood flow was less over the 30 weeks for people taking Camzyos.
NYHA class. More than twice as many people taking Camzyos had an improvement in their NYHA Class (65%), compared with people taking the placebo (31%). By week 30, 50% of people taking Camzyos moved from a Class II or III down to Class I, compared with 21% for people taking the placebo. This means that people had fewer symptoms and were able to do more physical activities without worsening symptoms.
Patient-reported outcomes. The KCCQ-CSS score was three times higher, and the HCMSQ-SoB score was three times lower for people taking Camzyos, which means that people reported less frequent and less severe symptoms, compared to people taking the placebo. For the KCCQ-CSS, people taking Camzyos had an average improvement in scores by 14 points, compared to 4 in the people taking the placebo. A higher score means that people reported less severe symptoms and less impact on physical activity. For HCMSQ-SoB, people taking Camzyos had a 3-point lower score, compared to only a 1-point change for people taking the placebo. This shows that people reported less shortness of breath while taking Camzyos.
In Study 2, Camzyos reduced the number of people who were able to avoid SRT by week 16. Over three times more people no longer met the criteria for SRT (82%), compared with people taking the placebo (23%). People taking Camzyos also had similar results as the study above when looking at the following individual measures. This shows that a person taking Camzyos may see improvement in symptoms, the ability to do daily tasks with fewer symptoms, and may be able to delay or prevent SRT.
LVOT gradients. An LVOT gradient higher than 50 mmHg is a criterion for SRT. At the end of 16 weeks, the average decrease in LVOT gradient after exercise was 39 mmHg for people taking Camzyos, compared with 2 mmHg for people taking the placebo. The peak average was 43 mmHg, which means that on average, a person taking Camzyos would fall below the LVOT criteria. The peak average for the placebo remained high, at 83 mmHg.
NYHA class. Three times as many people taking Camzyos had an improvement in their NYHA Class (63%), compared with people taking the placebo (21%). This means that people had fewer symptoms, and they were able to do more physical activities without worsening symptoms.
Patient-reported outcomes. The KCCQ-23-CSS score was five times higher for people taking Camzyos. The average change in score was 10 mmHg for people taking Camzyos, compared with 2 mmHg for people taking the placebo. This means they reported less frequent and less severe symptoms, compared to people taking the placebo.
Your results may differ from what was seen in clinical studies. You and your health care provider should determine if the benefits outweigh any potential risks.
Signs That the Medicine Is Working
After a few months, your symptoms may get less frequent or less severe. You may see some of the following changes.
- Reduced shortness of breath or fatigue
- Increase in physical activity
- Improvement in quality of life
Camzyos works gradually, so you may not see quick changes in your symptoms. The long-term goal is to slow progression, so it is important to track your symptoms and review with your health care provider. Always continue your medicine even if you don’t feel changes in your symptoms right away. Your health care provider may also monitor your heart through different blood, imaging, or physical tests.
Are There Any Reasons Why I Should Not Take Camzyos?
Several medicines can affect the blood levels of Camzyos and should not be taken at the same time. These include strong CYP219 or CYP3A4 inhibitors and moderate to strong CYP2C19 or CYP3A4 inducers, (See the Interactions section below.) Tell your pharmacist or other health care provider about all the prescription or over-the-counter medicines, vitamins/minerals, herbal products, or other supplements you take or have recently taken.
How Can I Prevent and Manage Side Effects?
The most common side effects are heart failure, dizziness, and fainting. Tell your health care provider if you have any episodes of dizziness or fainting. Until you know how Camzyos will affect you, be careful changing positions quickly, especially when getting up. Be sure to drink plenty of water to prevent dehydration, especially in hot weather or during exercise.
Heart failure is a condition where the heart is not pumping as well as it should, which can be serious. Your health care provider may complete tests to check the health of your heart before starting Camzyos. Certain medicines, serious infections, or an irregular heartbeat can increase your risk of heart failure. Tell your health care provider right away if you have any of the following new or worsening symptoms of heart failure:
- Shortness of breath or trouble breathing, especially while lying down
- Swelling in your feet, ankles, or legs
- Unusually fast weight gain
- Unusual tiredness
These are not all of the possible side effects. Talk with your health care provider if you are having symptoms that bother you. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.
What Monitoring or Blood Tests May I Need?
Your health care provider may do the following tests before and during your treatment due to the risk of side effects.
Pregnancy. Camzyos can harm your unborn baby. Your health care provider may do a pregnancy test before starting Camzyos to confirm the absence of a pregnancy. Tell your health care provider if you are pregnant or plan to become pregnant before starting Camzyos.
Echocardiogram. An echocardiogram is required before and during treatment with Camzyos due to the risk of heart failure. This test is used to see how your heart muscle and valves are working. Your health care provider uses the following measurements from the test to find out if Camzyos should be continued and if the dose needs to be adjusted.
- Left ventricular ejection fraction (LVEF) is a measurement of the amount of blood leaving the left chamber (ventricle), which is where blood is pumped out of your heart to the rest of the body. A lower percentage is a sign of damage, like heart failure.
- Valsalva left ventricular outflow tract (LVOT), which measures the pressure difference between the left chamber and the aorta when the heart muscle is contracting. In HCM, higher LVOT measurements indicate more obstruction.
What Types of Interactions Can Happen?
Several medicines can interact with Camzyos. Before taking Camzyos, tell your health care provider about any prescription or over-the-counter medicines, vitamins/minerals, herbal products, and other supplements you are using.
Blood levels of Camzyos. Several medicines can change the blood levels of Camzyos. This may increase the risk of side effects, including heart failure, or may make Camzyos less effective. These changes are related to the effect of these medicines on enzymes called CYP. Ask your health care provider if you are using any of the following medicines or foods that change these enzymes.
Inhibitors of CYP2C19 or CYP3A4 enzymes may increase the levels of Camzyos and increase the risk of side effects. The following medicines or foods should not be used at the same time as Camzyos.
- Moderate to strong CYP2C19 inhibitors, including cenobamate (Xcopri), felbamate (Felbatol), fluconazole (Diflucan), fluoxetine (Prozac), fluvoxamine (Luvox), omeprazole (Prilosec), ticlopidine (Ticlid), and voriconazole (Vfend)
- Strong CYP3A4 inhibitors, including ceritinib (Zykadia), clarithromycin (Biaxin), idelalisib (Zydelig), itraconazole (Sporanox, Tolsura), and ketoconazole (Nizoral), along with medicines used for HIV (like elvitegravir/ritonavir and indinavir/ritonavir) and grapefruit or grapefruit juice
Other inhibitors of CYP2C19 or CYP3A4 enzymes may increase the levels of Camzyos and increase the risk of side effects. For these medicines, the dose may be adjusted by your health care provider.
- Weak CYP2C19 inhibitors, including cimetidine (Tagamet), felbamate (Felbatol), modafinil (Provigil), and rucaparib (Rubraca); and moderate CYP3A4 inhibitors, including aprepitant (Emend, Aponvie, Cinvanti), ciprofloxacin (Cipro), conivaptan (Vaprisol), crizotinib (Xalkori), diltiazem (Cardizem), dronedarone (Multaq), erythromycin, imatinib (Gleevec), verapamil (Isoptin, Calan), and grapefruit or grapefruit juice
Inducers of CYP2C19 or CYP3A4 enzymes may lower the levels of Camzyos and make it less effective. The following medicines should not be used at the same time as Camzyos.
- Moderate to strong CYP2C19 inducers, including apalutamide (Erleada), efavirenz (Sustiva), enzalutamide (Xtandi), phenytoin (Dilantin), and rifampin (Rifadin, Rimactane, Rifampicin)
- Moderate to strong CYP3A4 inducers, including apalutamide (Erleada), bosentan (Tracleer), carbamazepine (Tegretol, Equetro, Epitol), cenobamate (Xcopri), dabrafenib (Tafinlar), efavirenz (Sustiva), enzalutamide (Xtandi), etravirine (Intelence), ivosidenib (Tibsovo), lorlatinib (Lorbrena), lumacaftor/ivacaftor (Orkambi), mitotane (Lysodren), pexidartinib (Turalio), phenobarbital (Sezaby), phenytoin (Dilantin), primidone (Mysoline), rifampin (Rifadin, Rimactane, Rifampicin), and sotorasib (Lumakras), along with St. John’s wort
Blood levels of other medicines. Camzyos can affect the blood levels of some medicines. These changes are related to the effect on these medicines by an enzyme called CYP. This may increase the risk of side effects from these medications. Ask your health care provider if you are using any of the following medicines.
- Many CYP3A4 substrates, including but limited to alprazolam (Xanax), atorvastatin (Lipitor), budesonide-containing medicines, buspirone (BuSpar, Buspirex, Bustab), colchicine (Colcrys, Mitigare, Gloperba, Lodoco), eletriptan (Relpax), eplerenone (Inspra), everolimus (Afinitor, Zortress), lovastatin (Mevacor, Altoprev), midazolam (Versed), sildenafil (Viagra), simvastatin (Zocor), sirolimus (Rapamune), and tadalafil (Adcirca, Cialis, Alyq, Tadliq, Chewtadzy)
- CYP2C9 substrates, including celecoxib (Celebrex), glimepiride (Amaryl), tolbutamide (Orinase), and warfarin (Coumadin)
- CYP2C19 substrates, including diazepam (Valium, Diastat AcuDial, Valtoco)
Birth control. Camzyos may make birth control medicines called combined hormonal contraceptives less effective. Talk to your health care provider about the right birth control while you are taking Camzyos and up to 4 months after stopping Camzyos.
Negative inotropes. Negative inotropes are medicines that change the contraction of the heart muscle, decrease the amount of blood that is pumped, and decrease blood pressure and/or heart rate. Camzyos can have similar effects on the heart, which may increase the risk of side effects. Talk to your health care provider if you are taking any of the following medicines.
- Disopyramide (Norpace), which is commonly used for certain heart rhythm problems
- Ranolazine (Ranexa, Aspruzyo Sprinkles), which is commonly used for chest pain
- A calcium channel blocker, like verapamil (Verelan, Verelan PM, Calan, Calan SR) or diltiazem (Cardizem), which is commonly used for blood pressure or controlling heart rhythm
- A beta-blocker medicine, like atenolol (Tenormin) or metoprolol (Lopressor, Toprol XL)
This is not a complete list of medicines that may interact with Camzyos. Tell your pharmacist or other health care provider about all the prescription or over-the-counter medicines, vitamins/minerals, herbal products, or other supplements you take or have recently taken. This will help them determine if there are any interactions, or if you need a dosage adjustment.
Getting Your Medicine: What to Expect
Camzyos is part of the FDA’s Risk Evaluation and Mitigation Strategy (REMS) program. This is a program required by the FDA for medicines that have potential serious side effects. The goal is to inform you and your health care provider about the risks and how to manage and monitor symptoms during treatment. The drugmaker has a program to help support the process. You can find out more at https://www.camzyosrems.com/ or by calling 833-993-2242.
Here are some differences that you may expect.
Health care provider enrollment. Your health care provider will need to enroll in the REMS program and be certified to prescribe Camzyos. This should only take a few days.
Safety information and monitoring. Your health care provider will give you an overview of the safety concerns and give you a patient brochure. Before starting Camzyos and during treatment, your health care provider will perform an echocardiogram to check how your heart is working and will review your medical history and medicines you are taking.
Insurance approval. Your insurance may require approval for using this medicine, also called prior authorization. The insurance company reviews the prescription from your health care provider to make sure it is covered and determines the process that needs to be followed.
Specialty pharmacy. You may be required to use a specialty pharmacy to get Camzyos each month. The pharmacist helps with instructions on how to take and store the medicine, monitors side effects, and tracks refills. This pharmacy will also work with you on how to get Camzyos, either at a store or through the mail. Your health care provider will locate a Camzyos REMS-certified pharmacy to use.
Cost assistance. There is a copay assistance program from the drugmaker that may allow you to pay $0 for your prescription. Whether you are eligible depends on whether you have prescription insurance and what type of insurance you have. You can find out more at https://www.camzyos.com/mycamzyos-patient-support-sign-up/overview or by calling 855-226-9967.
