EXPLORER-HCM top-line results: Mavacamten improves symptoms, quality of life, functional status
MyoKardia announced top-line results from the EXPLORER-HCM clinical trial in patients with symptomatic obstructive hypertrophic cardiomyopathy showing that the trial met its primary and secondary endpoints.
The primary endpoint, a composite functional analysis to assess the effect of mavacamten on symptoms and function compared with placebo, was met (P = .0005), according to a press release issued by the company.
All secondary endpoints were also met, including improvements in NYHA functional classification (P < .0001), post-exercise left ventricular outflow tract peak gradient (P < .0001), Kansas City Cardiomyopathy Clinical Summary Score (P < .0001), peak VO2 (P = .0006) and the HCM Symptom Questionnaire Shortness of Breath Domain Score (P < .0001), according to the release.
The drug was safe and well tolerated, the company stated in the release.
“The extraordinary data from the EXPLORER pivotal trial confirm mavacamten’s ability to relieve dynamic outflow obstruction, control symptoms and improve quality of life in patients with hypertrophic cardiomyopathy,” Iacopo Olivotto, MD, staff physician at Careggi University Hospital in Florence, Italy, and lead clinical investigator of the EXPLORER-HCM trial, said in the release. “Mavacamten is the first drug developed to target the specific molecular defect of the disease. EXPLORER represents a major achievement toward a precision-medicine approach in cardiomyopathies and should provide great hope to a community painfully aware of the lack of disease-specific treatment options.”
The EXPLORER-HCM trial assessed 251 patients with symptomatic obstructive hypertrophic cardiomyopathy (HCM) who were assigned mavacamten once per day or placebo. Patients assigned mavacamten started with a 5 mg dose, which could be adjusted up to two times by 2.5 mg to 15 mg based on a combination of factors including drug plasma concentration, residual LV outflow tract and LV ejection fraction levels, according to the release. Patients received treatment for 30 weeks.
“The resoundingly positive data from EXPLORER bring us a significant step closer to improving the lives of people with serious cardiovascular conditions starting with HCM, a debilitating disease estimated to affect 1 in every 500 people,” Tassos Gianakakos, CEO of MyoKardia, said in the release. “The activity and tolerability profile observed for mavacamten in this pivotal study underscores the profound impact and potential for therapeutics that target the underlying biology of disease.”
MyoKardia plans to submit a new drug application to the FDA in the first quarter of 2021 and anticipates submitting these data to a future meeting in 2020, according to the release.
Disclosures: Olivotto is the lead clinical investigator for the EXPLORER-HCM trial. Gianakakos is an employee of MyoKardia.