Milestone's lead product candidate, etripamil, is currently in a Phase III program for the treatment of paroxysmal supraventricular tachycardia (PSVT) and in a Phase II proof-of-concept trial for the treatment of patients with atrial fibrillation with rapid ventricular rate.

In October 2022, Milestone announced positive top-line efficacy and safety data from the Phase III RAPID clinical trial of etripamil in PSVT.