Milestone Pharmaceuticals Inc (Nasdaq: MIST), a biopharmaceutical company focused on the development and commercialisation of innovative cardiovascular medicines, has revealed top-line results from its phase three, multi-centre, randomised, double-blind, placebo-controlled NODE-301 trial of its investigational new drug, Etripamil nasal spray, it was reported on Monday.

The etripamil nasal spray is the company's novel short-acting calcium channel blocker and is intended for patients with paroxysmal supraventricular tachycardia (PSVT).

The NODE-301 trial enrolled a total of 431 patients across 65 sites in the United States and Canada and is an event-driven Phase three efficacy trial of etripamil for terminating supraventricular tachycardia (SVT) episodes in the at-home setting. Etripamil (70mg) did not achieve its primary endpoint of time to conversion of supraventricular tachycardia SVT to sinus rhythm (SR) compared to placebo over the five hour period following study drug administration (median time to conversion of 25 minutes [95% CI: 16, 43] for etripamil compared to 50 minutes [95% CI: 31,101] for placebo, p=0.12). Despite early activity, including the conversion of 61% of etripamil patients compared to 45% of placebo patients by 45 minutes (p=0.02), a time period consistent with etripamil's known pharmacological activity, results from the latter part of the analysis confounded the statistical analysis of the primary endpoint.

The study demonstrated statistically significant improvements in favour of etripamil over placebo in the important secondary endpoint of patient reported treatment satisfaction, as measured by a treatment satisfaction questionnaire for medication (TSQM-9).