- Topline data from MyoKardia’s Phase 2 PIONEER-HCM study of mavacamten in symptomatic, obstructive hypertrophic cardiomyopathy (oHCM) has shown enough benefit to encourage MyoKardia to seek a regulatory ok to start a pivotal study later this year.
- After 12 weeks of treatment, all 10 patients who completed the study showed a reduction in post-exercise peak left ventricular outflow tract (LVOT) gradient, with eight reaching a post-exercise peak LVOT gradient of ≤30 mmHg, below the diagnostic threshold for the disease.
- There was one serious adverse event in a patient with a history of paroxysmal atrial fibrillation who had discontinued background beta blocker and disopyramide therapy. Th patient discontinued the study drug following recurrent episodes of atrial fibrillation. The Independent Data Monitoring Committee (IDMC) recommended continuation of the study.
The market is taking a positive view on MyoKardia today, after it reported topline cardiomyopathy data and its second quarter financial results. Mavacamten has been developed as part of a 2014 collaboration between Sanofi and MyoKardia to develop therapies for patients with genetic cardiomyopathies, under Sanofi’s Sunrise Initiative to invest in early-stage opportunities.
As part of a next step, MyoKardia will meet with the Food and Drug Administration for an end of Phase 2 meeting to gain feedback on whether its EXPLORER-HCM study, which will use peak VO2 as the primary endpoint, can be used as a pivotal study. The company expects to enroll between 200-250 patients and seeks to begin enrollment before the end of the year.
While the PIONEER-HCM study only inlcuded a very small number of patients, the treatment effect was signficant enough to push MyoKarida to plow rapidly ahead with the genetic heart defect drug. If the FDA gives the ok to move to pivotal studies, bypassing another Phase 2 study, the biotech could cut a huge chunk of time out of the drug’s development.
A second, lower-dose cohort has completed enrollment in the PIONEER-HCM study. MyoKardia is testing lower doses due to the high rate of efficacy seen in the first patient cohort. Data from those patients are expected in the first quarter of 2018.
“We are positioned for a successful second half of 2017 with several key clinical and regulatory developments expected on the heels of the positive topline data announced today from PIONEER-HCM,” said Tassos Gianakakos, CEO. “We have made great progress across our entire pipeline, both clinical-stage and research-stage programs, that strengthens our confidence in MyoKardia’s unique approach to treat heritable cardiomyopathies.”
MyoKardia expects that its cash, cash equivalents, investments and payments from Sanofi will keep it operating until at least 2019.
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