People with a common heart disease were able to use significantly more oxygen while exercising after taking an investigational drug in an international clinical trial, according to a study published today in the journal New England Journal of Medicine. The finding was also presented today at the European Society of Cardiology’s 2024 Heart Failure meeting in Lisbon, Portugal.
Oregon Health & Science University is part of the randomized, double-blind Phase 3 trial evaluating the experimental drug aficamten, developed by Cytokinetics to treat the obstructive form of hypertrophic cardiomyopathy, or HCM. Of the 282 adults who participated in the trial, 19 enrolled through OHSU, the most of any trial site.
“By having more oxygen available during exercise, patients with hypertrophic obstructive cardiomyopathy can walk more easily, perform housework and other daily tasks,” the cardiologist said. Ahmad Masri, MD, MS, who co-wrote today’s article and directs the Hypertrophic Cardiomyopathy Center at OHSU’s Knight Cardiovascular Institute. “Results from our latest clinical trials suggest that aficamten is a promising treatment for HCM.”
HCM affects approximately 1 in 500 people and is one of the most common causes of sudden death among young people and healthy athletes. Often caused by inherited genetic mutations, it thickens the heart muscles and makes it difficult for the heart to function as it should. It causes shortness of breath and reduces people’s ability to exercise. The obstructive form of HCM reduces blood flow out of the heart.
About half of the trial participants received the experimental drug and the other half took a placebo and served as the study’s control group. The scientists measured the participants’ oxygen levels while they used treadmills or bicycles. Those taking aficamten had a significant increase in their peak oxygen use: 1.7 milliliters per kilogram per minute more than those in the control group.
Having a higher maximum oxygen consumption can improve a patient’s ability to be physically active, while reduced oxygen consumption can increase the risk of heart failure, needing a heart transplant, and death.
Non-drug treatment options for obstructive HCM include surgery to remove excess heart muscle. In 2022, the Food and Drug Administration also approved mavacamten as the first drug designed to target the underlying cause of obstructive HCM. However, mavacamten may increase the risk of heart failure and interacts with several commonly used medications. As a result, patients using mavacamten must also undergo intensive monitoring.
Over the past decade, OHSU has participated in many research studies exploring new treatment options for HCM. It has been the center of several mavacamten studies and participates in gene therapy research. The university is also currently involved in four other trials of aficamten evaluating it as a potential treatment for various forms of HCM and in different types of patients, including children.
“This is an exciting time for HCM treatment,” Masri said. “While we continue to offer traditional surgical and procedural therapies for HCM, we are now also able to offer patients other treatment options: therapies that were recently approved by the FDA and investigational therapies that are available through participation in clinical trials.”