Edgewise falls on safety, efficacy doubts for heart disease drug

Shares of biopharma firm Edgewise Therapeutics EWTX fall 39.4% to $12.20

EWTX says its experimental drug, EDG-7500, when tested in patients with Hypertrophic cardiomyopathy (HCM), was able to meaningfully reduce LVOT gradients, a predictor of heart failure

But patients who took the drug reported dizziness and respiratory tract infections, with one patient discontinuing the trial due to dizziness

Brokerage RBC Capital Market says "while there may be some questions around safety, we think the profile is manageable"

RBC says the efficacy markers from this trial are "relatively modest" compared with early-stage study data

Shares of rival Cytokinetics CYTK.O, which is developing experimental heart drug aficamten, rise 12% to $42

HCM is characterized by thickening of the heart muscle, affecting its ability to pump blood

As of last close, EWTX has risen 11.7% in the past 12 months