Bristol Myers falls as heart disease drug fails in late-stage trial

** Shares of drugmaker Bristol Myers Squibb BMY.N fall 1.6% to $50.50 in extended trading

** Co says its experimental heart disease drug, mavacamten, did not meet the main goals in a late-stage study

** The drug was being tested to treat adult patients with with the so-called non-obstructive form of hypertrophic cardiomyopathy (nHCM), an inherited condition characterized by thickening of heart muscles

** The drug, branded as Camzyos, did not improve symptoms or exercise more easily in patients with nHCM

** The drug is already approved in the U.S. for the obstructive form of the disease

** As of last close, stock down 9.2% YTD