Drug Trials Snapshots: CARDAMYST

Why It Matters

CARDAMYST offers the first FDA‑approved at‑home, self‑administered therapy for PSVT, potentially reducing emergency visits and expanding treatment options for a condition that currently relies on in‑clinic interventions.

Key Takeaways

• Nasal spray converts 49.6% vs 22.7% placebo
• Hazard ratio 2.59, p<0.001
• Most common side effects nasal discomfort, congestion
• Efficacy consistent across sex and age groups
• FDA approved Dec 12 2025 for adult PSVT

Pulse Analysis

Paroxysmal supraventricular tachycardia (PSVT) affects millions of adults worldwide, often prompting urgent care visits for rapid rhythm control. Traditional management relies on vagal maneuvers, intravenous adenosine, or electrophysiological ablation—options that require clinical supervision and can be distressing for patients. CARDAMYST, a calcium‑channel blocker delivered via nasal spray, fills a critical gap by enabling immediate, self‑administered therapy at the onset of symptoms, aligning with the broader trend toward decentralized, patient‑centric care.

The RAPID phase III trial, a double‑blind, placebo‑controlled study across 160 sites in eight nations, enrolled 255 participants with documented PSVT. Patients self‑treated during an episode, and the primary endpoint—time to conversion to sinus rhythm within 30 minutes—favored CARDAMYST, achieving a 49.6% conversion rate versus 22.7% for placebo. The hazard ratio of 2.59 (95% CI 1.64‑4.09) and a p‑value below 0.001 underscore robust efficacy. Subgroup analyses revealed comparable benefits for females and males, as well as for patients under and over 70, suggesting broad applicability across the typical PSVT demographic.

Safety data indicate that while CARDAMYST is generally well tolerated, nasal irritation is common, affecting 39% of treated subjects compared with 9% on placebo. Serious cardiovascular events were rare, but clinicians should monitor blood pressure and heart rate due to the drug’s vasodilatory properties. The favorable risk‑benefit profile, combined with the convenience of at‑home administration, positions CARDAMYST to capture a sizable share of the acute arrhythmia market, potentially reducing emergency department utilization and driving new revenue streams for Milestone Pharmaceuticals.