Milestone Pharmaceuticals Faces FDA Setbacks and Losses

Introduction

MILESTONE PHARMACEUTICALS INC (Nasdaq: MIST) is a clinical-stage biopharmaceutical company based in Montreal, Quebec. As of July 11, 2025, its shares closed at USD 1.7650, a decrease of 31.05% from the prior trading session, with a trading volume of 675,231 shares. Milestone focuses on developing self-administered therapies for acute cardiovascular episodes outside of hospital settings.

Corporate Structure

Founded in 2007, Milestone Pharmaceuticals operates with 11–50 employees. Its leadership team comprises professionals with experience from major pharmaceutical companies and emerging life sciences firms. The company's core asset, etripamil (branded CARDAMYST), is a nasal spray calcium channel blocker designed for the at-home termination of paroxysmal supraventricular tachycardia (PSVT) and atrial fibrillation with rapid ventricular rate (AFib-RVR).

Cardiovascular therapy by Ali Hajiluyi

Recent Developments and News

• FDA Complete Response Letter (March 2025): The FDA issued a Complete Response Letter (CRL) citing two Chemistry, Manufacturing, and Controls (CMC) issues regarding CARDAMYST: a request for additional data on nitrosamine impurities and the need for a facility inspection following a change in ownership. Milestone has requested a Type A meeting to discuss the resolution of these issues.
• Q1 2025 Financial Results (May 14, 2025): Milestone reported no revenue for Q1 2025, with a net loss of USD 20.8 million, compared to a net loss of USD 10.4 million in Q1 2024. Research and development expenses amounted to USD 5.0 million (Q1 2024: USD 3.6 million), while general and administrative expenses were USD 5.2 million (Q1 2024: USD 4.0 million). As of March 31, 2025, cash, cash equivalents, and short-term investments totaled USD 56.0 million, down from USD 69.7 million as of December 31, 2024.
• Patent Extension (May 2025): The U.S. Patent and Trademark Office issued U.S. Patent No. 12,257,224 for the repeat-dose regimen of CARDAMYST utilized in its Phase 3 RAPID study, which could extend U.S. exclusivity until July 2042.
• Managed Care Survey (May 6, 2025): An independent survey conducted by Managed Healthcare Executive and The American Journal of Managed Care indicated that 40% of respondents anticipate CARDAMYST to be the most impactful new cardiovascular therapy.
• AFib-RVR Phase 3 Protocol: The FDA has approved the Phase 3 study design for etripamil in AFib-RVR; however, enrollment is on hold until the CRL related to PSVT is resolved.
• Equity and Warrant Offering (July 11, 2025): Milestone filed a preliminary prospectus (Form 424B5) for an offering of common shares, pre-funded warrants, and Series A and B warrants aimed at strengthening its cash position.

Financial and Strategic Analysis

Milestone's Q1 2025 performance reflects a cash-burn profile in the absence of product revenue. The reported cash balance of USD 56.0 million is anticipated to fund operations into late 2025, contingent upon capital market conditions and timelines associated with FDA engagement. The CMC issues noted in the CRL are procedural; the FDA identified no safety or efficacy concerns, but the resolution of these matters might delay commercial launch and necessitate additional financing. The extended patent protection until July 2042 may enhance long-term value. The offering filed on July 11, 2025, is intended to support CRL resolution, prepare for potential commercialization of CARDAMYST, and restart AFib-RVR enrollment.

Market Position and Industry Context

Milestone addresses a specific need in acute cardiovascular care by facilitating at-home treatment of PSVT and AFib-RVR. The nasal spray formulation of etripamil distinguishes it from conventional intravenous and oral therapies. The findings from the managed care survey, along with the novel delivery mechanism, position CARDAMYST strategically against existing hospital-based treatments. However, Milestone's transition from a research-focused entity to a commercial biopharmaceutical company remains dependent on FDA approval and the successful acquisition of further capital.

tl;dr

Milestone Pharmaceuticals (Nasdaq: MIST) closed at USD 1.7650 on July 11, 2025, following a 31.05% decline. The FDA issued a CRL for CARDAMYST in March 2025 due to manufacturing concerns; a Type A meeting is pending. As of Q1 2025, cash stood at USD 56.0 million, with no revenue reported and a net loss of USD 20.8 million. Patent protection now extends through July 2042. Enrollment in the AFib-RVR Phase 3 trial is currently paused. A prospectus filed on July 11, 2025, outlines an equity and warrant offering for financing CRL resolution and operational support.