MyoKardia’s stock prices jumped today after their recent Stage II trial of the experimental drug mavacamten (formally known as MYK-461)  demonstrated a statistically significant reduction to left ventricular outflow tract gradients as well as improvement to aerobic capacity in patients with obstructive hypertrophic cardiomyopathy.  

Of the 10 patients who completed the study, 8 saw their gradient reduced to normal levels after 12 weeks on the drug.  The study also showed improvements in both peak oxygen consumption (peak VO2) and New York Heart Association classifications:  7 patients moved up one NYHA class while 2 patients improved by two classes.

The drug seemed to have mild to moderate side effects, though one patient was forced to drop out of the trial due to a recurrence of atrial fibrillation which necessitated discontinuation of mavacamten and a return to anti-arrythmic drugs which had been discontinued due to participation in the trial.

MyoKardia hopes to enroll between 200 and 250 patients in its next phase trial (Explorer HCM) which it plans to begin before the end of 2017.

MyoKardia also plans a clinical trial of mavacamten in non-obstructive HCM patients in the second half of 2017.

For more information on MyoKardia and  recent drugs being developed for HCM read these past blog entries:

MyoKardia HCM Drug Has Success in Cats

End of the Road for Eleclazine and Liberty HCM Study

HCM Drug Trial Advances to Next Round

Drug for Non-Obstructive HCM Moves Along