MyoKardia has dosed the first patient in its Phase II trial of mavacamten for the treatment of non-obstructive hypertrophic cardiomyopathy (nHCM), a sub-type of HCM.
The placebo-controlled MAVERICK-HCM trial is designed to analyse the safety and tolerability of a 16-week treatment course of mavacamten.
The trial’s secondary endpoints include the effect of mavacamten on exercise capacity as measured by peak oxygen uptake, changes in NYHA functional classification, diastolic and systolic function as measured by echocardiography, symptoms and quality of life measures, as well as NT pro-BNP levels and patient activity as measured by a wrist-worn accelerometer.
Around 60 patients with nHCM and preserved left ventricular ejection fraction are expected to be included in the trial.
Participants will be randomised evenly into three groups and given a once-daily dose of mavacamten targeting one of two plasma concentration levels of drug or placebo.
The trial will evaluate the pharmacokinetics (PK) level in each patient at week four, and the dose at week six will be adjusted to achieve the target drug concentration.
During the MAVERICK-HCM trial, patients will be allowed to maintain background medications including beta blockers or calcium channel blockers.
Apart from the 16-week treatment period, patients will take part in a screening period of up to four weeks and will be monitored for an additional eight weeks after discontinuation of mavacamten.
Topline data from the trial are expected to be available in the second half of next year.
MAVERICK-HCM principal investigator Dr Stephen Heitner said: “Patients with nHCM tend to get diagnosed once their disease is quite advanced, by which time they are already experiencing symptoms that force them to restrict their regular everyday activities.
“With no approved therapeutic interventions available, current treatment options are limited to off-label medications aimed at symptom relief, or heart transplant.
“The prospect of a pill that could reduce the hypercontractility that underpins this disease and improve patients’ ability to function could truly change the nHCM treatment paradigm.”
MyoKardia has been evaluating mavacamten through six clinical trials, which have so far proved the solution to be generally well-tolerated.