Written By: Pharmacally Medical News Desk
Milestone Pharmaceuticals has received U.S. Food and Drug Administration (FDA) approval for CARDAMYST™ (etripamil) nasal spray, making it the first and only self-administered, rapid-acting nasal therapy for adults with paroxysmal supraventricular tachycardia (PSVT). The company expects CARDAMYST to be available through retail pharmacies in the first quarter of 2026, following completion of launch and access preparations.
PSVT is a common supraventricular arrhythmia marked by sudden episodes of rapid heart rate that often begin without warning. Although not usually life-threatening, episodes can be highly symptomatic and frequently lead to emergency department visits when they fail to resolve spontaneously.
Joseph Oliveto, President and Chief Executive Officer of Milestone Pharmaceuticals, described the approval as a significant milestone for the company and the PSVT community, emphasizing the value of an at-the-ready treatment option for an unpredictable condition.
A self-administered, on-demand approach
CARDAMYST is designed for at-the-ready use during a PSVT episode, allowing appropriate patients to self-administer treatment outside of hospital settings. The therapy contains etripamil, a short-acting calcium channel blocker formulated for intranasal delivery, enabling rapid systemic absorption and a brief duration of action aligned with episodic arrhythmias.
This approach differs from current acute management options, which often rely on vagal maneuvers or intravenous medications administered under medical supervision. By enabling timely treatment at symptom onset, CARDAMYST may reduce the need for urgent care in selected patients.
Etripamil is a short-acting, non-dihydropyridine calcium channel blocker that works by temporarily slowing electrical conduction through the atrioventricular (AV) node, a key structure involved in most forms of paroxysmal supraventricular tachycardia.
Clinical evidence supporting approval
The FDA approval was supported by Milestone’s late-stage clinical development program, including the Phase 3 RAPID trial, a global, randomized, double-blind study comparing CARDAMYST to placebo in adults with PSVT who self-administered treatment during symptomatic episodes.
In the RAPID trial, 64% of participants who received CARDAMYST (N=99) converted from supraventricular tachycardia to normal sinus rhythm within 30 minutes, compared with 31% of those receiving placebo (N=85). After one hour, conversion to sinus rhythm was observed in 73% of patients treated with CARDAMYST.
CARDAMYST also demonstrated a faster and more durable time to conversion, with a median time to sinus rhythm of 17 minutes versus 54 minutes for placebo. Separation between treatment groups occurred early and was maintained over time. The safety profile was consistent with prior studies, with most adverse events reported as mild to moderate and primarily related to nasal administration.
Key Opinion
Lorenz Muller, Chief Commercial Officer of Milestone Pharmaceuticals, said, “Our goal is that CARDAMYST will become a trusted and essential solution for healthcare providers and their patients.” He also noted that the company is actively working to secure insurance coverage and establish retail pharmacy distribution to support broad access following launch.
From a clinical perspective, James Ip, M.D., FACC, FHRS, an etripamil investigator, highlighted the burden PSVT places on patients, including anxiety related to sudden episodes and frequent emergency care. He noted that a self-administered option capable of rapidly terminating episodes may help some patients avoid hospital visits or emergency services.
Until now, acute management of PSVT has largely depended on emergency care or supervised intravenous therapy. CARDAMYST introduces a patient-controlled, outpatient approach that may reduce healthcare utilization while preserving safety through appropriate patient selection and physician guidance.
CARDAMYST is intended for adults with a confirmed diagnosis of PSVT and does not replace long-term rhythm management strategies or specialist follow-up.
Beyond PSVT, Milestone is preparing to advance intranasal etripamil into a Phase 3 program for atrial fibrillation with rapid ventricular rate (AFib-RVR), supported by encouraging findings from the ReVeRA Phase 2 trial. This program reflects a broader interest in rapid, noninvasive rate control strategies for acute arrhythmias.
The FDA approval of CARDAMYST (etripamil) marks a meaningful advance in the treatment landscape for PSVT. Supported by robust Phase 3 data, including rapid and sustained conversion to sinus rhythm, CARDAMYST offers a new, evidence-based option for self-administered, on-demand management of acute PSVT episodes, with U.S. availability anticipated in early 2026.
References
Milestone Receives FDA Approval of CARDAMYST™ (etripamil) as First and Only Self-Administered Nasal Spray for Adults with Paroxysmal Supraventricular Tachycardia (PSVT), 12 December 2025, https://investors.milestonepharma.com/news-releases/news-release-details/milestone-receives-fda-approval-cardamysttm-etripamil-first-and
Stambler, Bruce SIp, James E et al., self-administered intranasal etripamil using a symptom-prompted, repeat-dose regimen for atrioventricular-nodal-dependent supraventricular tachycardia (RAPID): a multicenter, randomised trial, The Lancet, Volume 402, Issue 10396, 118 – 128, DOI: 10.1016/S0140-6736(23)00776-6