MIST Stock Surges on Historic FDA Clearance: First Self-Administered PSVT Treatment

MIST (Milestone Pharmaceuticals Inc.) captured market attention this week following a landmark regulatory milestone. The company’s stock touched a 52-week high of $3.06 during intraday trading on Friday, December 12, 2025, before settling at $2.41—reflecting an 18.31% decline from that peak. The movement comes on the heels of groundbreaking FDA approval for CARDAMYST, a nasal spray treatment that represents a significant shift in how a common heart rhythm disorder is managed.

What Makes This FDA Approval Historic

CARDAMYST marks the first FDA-approved treatment for paroxysmal supraventricular tachycardia (PSVT) in more than three decades. Unlike traditional approaches requiring emergency department visits, this rapid-acting calcium channel blocker enables patients to self-administer treatment during acute episodes—a game-changer for the millions affected by this condition.

Understanding PSVT: The Patient Impact

Paroxysmal supraventricular tachycardia stems from electrical irregularities in the heart’s conduction system. The condition affects more than two million Americans, causing sudden episodes of accelerated heart rate ranging between 160 and 220 beats per minute, occasionally exceeding 250 bpm. These unpredictable episodes strike without warning, then cease spontaneously.

Patients typically experience a cluster of symptoms during attacks: heart palpitations, profuse sweating, chest discomfort or sharp pain, respiratory difficulties, sudden energy crashes, loss of consciousness, and overwhelming anxiety. Young people encounter this condition more frequently, particularly during periods of intense physical exertion.

The Clinical Advantage

Prior to CARDAMYST’s approval, PSVT management options were limited. The nasal spray’s rapid-acting formulation addresses a critical gap—allowing symptomatic patients immediate relief outside traditional healthcare settings. This represents a meaningful advancement in patient autonomy and quality of life.

Market Timeline and Availability

MIST plans to launch CARDAMYST in retail pharmacy locations beginning in the first quarter of 2026. The company will host a conference call and webcast on Monday, December 15, 2025, at 8:00 a.m. ET to discuss the approval and commercial strategy.

Stock Performance Context

MIST shares traded around $1.98 when previously highlighted on January 29, 2025. The recent volatility reflects typical market dynamics surrounding major FDA clearances—initial enthusiasm followed by profit-taking. Investors monitoring the biotech sector should note that this regulatory win establishes CARDAMYST as the first major commercial product for Milestone Pharmaceuticals, potentially reshaping the company’s revenue trajectory.

Disclaimer: This analysis represents market observations and does not constitute investment advice.