What happened

Shares of Myokardia Inc. (MYOK), a clinical-stage biotech developing treatments for inherited heart problems, took flight this morning. Positive data for its lead candidate propelled the stock 82.8% higher as of 11:42 a.m. EDT during Monday's session.

So what 

This morning, Myokardia announced results from a mid-stage clinical trial testing mavacamten's ability to help patients' abnormally strong hearts relax a little. The study met its main goal, lowering peak left ventricular outflow tract gradient for a small group of obstructive hypertrophic cardiomyopathy patients, with flying colors.

Big rocket blasting through the atmosphere into outer space.

Image source: Getty Images.

Beta blockers that slow these patients' heart rates and lower blood pressure help, but don't attack the root cause of the disease that leads to irreparable heart damage. Mavacamten had shown an ability to reduce overly strong heart contractions, but today's result is a much stronger hint that doing so might lead to a long-term survival benefit.

Now what

One patient initially enrolled in the group that provided today's data had to drop out early, possibly due to the trial protocol requiring patients to stop beta-blocker treatment before beginning the study. Myokardia recently completed enrollment of another group that will receive a lower dose of mavacamten while remaining on beta blockers. If this group shows similarly positive results, it could smooth out the path forward.

Although it wasn't the trial's main goal, Myokardia noted the 10 patients with 12 weeks of data showed a significant oxygen consumption increase. Based on today's interim results, the company intends to design its next study in a manner that could support a new drug application, possibly with increased oxygen consumption as the main goal.

Of course, investors will want to keep an eye out for news that the Food and Drug Administration might be willing to accept an application supported with data from a trial with a protocol similar to the mid-stage study that delivered winning results today. If it does, this stock could soar again.