Safety concerns overshadow efficacy highlights in MyoKardia’s cardiomyopathy data

Despite positive efficacy data for mavacamten across two hypertrophic cardiomyopathy trials, MyoKardia shares dropped $4.56 to $55.45 on Monday when investors picked up on signs that a narrow therapeutic window could bring safety risks.

In two presentations released in advance of the 2019 American Heart Association’s Scientific Sessions next week, MyoKardia Inc. (NASDAQ:MYOK) reported safety and efficacy data for its cardiac myosin inhibitor mavacamten in obstructive and non-obstructive hypertrophic cardiomyopathy (HCM). ...