Milestone Pharmaceuticals Inc. has announced the resubmission of its New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for etripamil nasal spray, an investigational product for the management of paroxysmal supraventricular tachycardia (PSVT). This action follows a Type A meeting with the FDA after the company received a Refusal to File (RTF) letter.
The resubmission package includes restructured data sets capturing the timing of reported adverse events and reformatted data files to facilitate the FDA’s analyses. Milestone Pharmaceuticals President and CEO Joseph Oliveto stated, “We appreciate FDA’s guidance through the resubmission process. We believe we have addressed all the issues raised in the Refusal to File letter and look forward to working with the Agency as it reviews our application.”
Addressing PSVT with Etripamil
PSVT, a type of arrhythmia, affects an estimated two million people in the United States. It is characterized by sudden episodes of rapid heartbeats, often exceeding 150 to 200 beats per minute. These episodes can last for several hours and cause severe palpitations, shortness of breath, chest discomfort, dizziness, and distress, significantly impacting patients' daily activities and provoking anxiety.
Many healthcare providers are dissatisfied with current treatment options, which often involve prolonged and costly emergency department visits or invasive cardiac ablation procedures. Etripamil, a novel calcium channel blocker nasal spray, is designed as a self-administered rapid response therapy, potentially bypassing the need for immediate medical oversight. If approved, it could provide patients with active management and a greater sense of control over their condition.
Etripamil's Potential Beyond PSVT
Etripamil is also under investigation for the treatment of atrial fibrillation with rapid ventricular rate (AFib-RVR). An estimated five million Americans suffer from atrial fibrillation (AFib), and a subset of these patients experience episodes of abnormally high heart rate. Milestone's market research suggests that 30 to 40% of patients with AFib experience one or more symptomatic episodes of RVR per year that require treatment, suggesting a target addressable market of approximately three to four million patients in 2030 for etripamil in patients with AFib-RVR.
CARDAMYST™, the conditionally approved brand name for etripamil nasal spray, has undergone a robust clinical trial program, including a completed Phase 3 clinical-stage program for PSVT and a Phase 2 trial for AFib-RVR.
