FDA Extends Review of Mavacamten to April 2022

The FDA has extended the review of Bristol Myers Squibb’s new drug application for mavacamten, which is being reviewed as a treatment for patients with symptomatic obstructive hypertrophic cardiomyopathy, to April 28, 2022.

The agency has extended the PDUFA date to assess information pertaining to updates to the proposed risk evaluation mitigation strategy (REMS). A REMS program was included in the initial application for mavacamten. No additional data or studies have been requested.

The Institute for Clinical and Economic Review (ICER), in a final evidence report, has found concerns about long-term safety indicate there may not be a benefit for mavacamten when added to first-line therapy. ICER estimates that for mavacamten to be cost-effective, it would need to be priced between $12,000 and $15,000 annually.

ICER recommends that payers use the label as a guide when determining coverage.

“The evidence suggests that mavacamten may deliver important health benefits for patients with a lower rate of side effects than seen with some other medications for HCM, but clinical experts differ in their opinions about the long-term clinical implications of mavacamten reducing left ventricular ejection fraction in some patients. Additional safety data are needed to resolve these issues, David Rind, M.D., ICER’s chief medical officer, said in a statement.

Hypertrophic cardiomyopathy is a chronic disease in which excessive contraction of the heart muscle can lead to the development of debilitating symptoms and cardiac dysfunction.

In patients with hypertrophic cardiomyopathy, the heart muscle becomes abnormally thick, making it harder for the heart to pump blood. The thickened heart muscle can cause shortness of breath, chest pain, or problems in the heart’s electrical system, resulting in life-threatening arrhythmias or sudden death, according to the Mayo Clinic.

In obstructive disease, the thickened heart wall can block or reduce the flow of blood from the left ventricle to the aorta.

It’s estimated that 1 in every 500 people have hypertrophic cardiomyopathy, but a large percentage of patients are undiagnosed, says the American Heart Association. Of those diagnosed, two-thirds have the obstructive form of the disease.

Commonly prescribed medications include beta blockers, anti-arrhythmic medications, calcium channel blockers, and anticoagulants, all therapies used to treat other cardiac conditions. Currently, no medication is available to specifically treat hypertrophic cardiomyopathy.