Mavacamten is Promising in Reducing Shortness of Breath in Cardiomyopathy

Woman holding her chest
Photo by Joice Kelly on Unsplash

A new drug, mavacamten, shows promise in providing relief to cardiomyopathy patients experiencing shortness of breath, according to new research presented at the American College of Cardiology (ACC) Scientific Session.

Dr Florian Rader presented results of an international clinical trial showing that mavacamten alleviated the shortness of breath in patients with obstructive hypertrophic cardiomyopathy.

The genetic condition causes thickening of the heart muscle, and as a result, heart muscle cells enlarge and scarring often develops between cells. Patients with the condition typically experience shortness of breath, chest pressure, irregular heartbeat, and, although rare, sudden cardiac arrest.

“Until now, existing treatments for hypertrophic cardiomyopathy have been suboptimal, leaving most patients symptomatic and often, in need of invasive or even open-heart surgery,” said Dr Rader, who served as site principal investigator of the clinical trial at Cedars-Sinai Hospital. “Follow-up data from this extended clinical trial shows success in lessening the obstruction to blood flow out of the heart in hypertrophic cardiomyopathy. Along with this relief of obstruction came substantial improvements in symptoms and an important heart failure blood biomarker.”

As Dr Rader explained, mavacamten showed preliminary success in relieving symptoms associated with the condition – chiefly, shortness of breath, which can be debilitating.

Key data from the clinical trial includes:

  • The average age of the 231 clinical trial participants was 60 years old, and 39% of those on the trial were female. The median follow-up was 62 weeks.
  • 69% of trial participants had improved shortness of breath after 48 weeks of treatment.
  • Treatment with mavacamten was generally well tolerated, and no new safety concerns were raised during longer-term follow-up.

Dr Rader said that no disease-specific targeted treatment options have been developed for the condition since it was first described some 60 years ago.

Though the prevalence of hypertrophic cardiomyopathy is roughly 1 in every 200 patients, Dr Rader said that the condition is thought to be widely underdiagnosed.

“A lot of patients have the condition and often feel short of breath or palpitations but their doctor doesn’t recognise these symptoms as stemming from hypertrophic cardiomyopathy,” Dr Rader said. “Instead, patients may be told by their physician they are out of shape, need to lose weight or are suffering from an anxiety condition.”

The correct approach, said Dr Rader, is to first pay close attention to the patient’s symptoms. If shortness of breath is a main concern, then a doctor should listen to the patient’s heart for a murmur, then follow up with an electrocardiogram, and, ultimately, an echocardiogram, which most often will lead to the correct diagnosis.

Source: Cedars-Sinai Medical Center