Milestone Pharmaceuticals Inc. (NASDAQ: MIST) announced the launch of RESET-PSVT, a Phase 4 multicenter registry designed to collect real-world data on CARDAMYST (etripamil) nasal spray usage in adults with paroxysmal supraventricular tachycardia.

The registry plans to enroll approximately 450 adult patients across 20 electrophysiology and cardiology sites, with enrollment expected to begin by the end of 2026. The Duke Clinical Research Institute will lead the study.

CARDAMYST received FDA approval in December 2025 and is commercially available in the United States for converting acute symptomatic episodes of PSVT to normal heart rhythm in adults.

The study's primary endpoint focuses on characterizing usage patterns of CARDAMYST in PSVT management, including episode frequency, usage frequency, doses per episode, and triggers for use. Secondary endpoints will compare CARDAMYST users with non-CARDAMYST users across quality of life measures, healthcare utilization, and episode characteristics.

"This registry is designed to help us better understand how CARDAMYST is being used in adults with PSVT in routine care," said David Bharucha, Chief Medical Officer of Milestone Pharmaceuticals.

The registry will evaluate patients prescribed CARDAMYST as well as those receiving other therapies. Enrolled patients and healthcare providers will complete outcome surveys as part of the data collection process.

Sean D. Pokorney, the study's lead investigator and Assistant Professor at Duke University School of Medicine, noted the registry aims to capture patient-reported outcomes in a contemporary PSVT population while informing real-world usage patterns.

Results from the registry are expected to be presented at scientific conferences and published in peer-reviewed publications. The company presented the study design at the Preventive Cardiovascular Nurses Association 2026 Cardiovascular Nursing Symposium in Scottsdale, Arizona.