Milestone Pharmaceuticals Inc. Q1 FY2026 earnings call

Commercial Launch of Cardamist

• Cardamist (Atripamil) was approved by the FDA on December 12, 2025, as the first and only rapid-acting, self-administered prescription therapy for acute PSVT episodes in adults. The company met its aggressive launch goal, making Cardamist available via retail pharmacies by the end of January 2026 and deploying a 60-person national sales force and starting promotion in mid-February 2026.
• Early adoption metrics show steady sequential growth: 100 prescriptions in February, 200 in March, 300 in April, totaling ~600 through end of April. These prescriptions were written by over 400 unique healthcare providers for ~560 unique patients, with broad early adoption across the provider base, seen as a positive signal of product-market fit.
• The company secured an early major win with Express Scripts, one of the three largest U.S. PBMs, adding Cardamist to its commercial national formulary, giving 25% of all commercially insured patients quality coverage with minimal prior authorization burden. Negotiations with other major PBMs and health plans are ongoing.
• Early feedback from healthcare providers and patients is overwhelmingly positive: providers quickly recognize the product's value based on its established mechanism and strong safety profile, and patients report increased security even if they have not yet used the drug, with positive outcomes for those who have used it.

Clinical Development Update

• The company has initiated the Phase III pivotal registration trial (Rivera 301) for Atripamil in AFib-RVR, building on positive Phase II results that showed statistically significant, clinically meaningful heart rate reduction and symptomatic improvement versus placebo.
• The trial is a double-blind, placebo-controlled, event-driven study that uses the same 70mg dose, self-administration design, and operational framework already validated in the PSVT Phase III program. First patient enrollment is expected in H2 2026.

Financial Position

• As of March 31, 2026, the company holds $184 million in cash, cash equivalents, and short-term investments, up from $106 million at December 31, 2025, driven by a $75 million payment from a royalty purchase agreement with RTW and ~$19 million in net proceeds from ATM sales and Series A warrant exercises.
• Q1 2026 operating cash burn was $23.7 million. R&D expense (net of tax credits) was $3.3 million, down from $5 million in Q1 2025 due to lower external drug development costs. G&A expense was $4.8 million, down from $5.2 million in Q1 2025 due to lower professional costs offset by higher personnel costs. Commercial expense was $15.8 million, up from $10.4 million in Q1 2025 due to launch-related personnel, professional, and operational costs. Net loss for Q1 2026 was $26.1 million ($0.20 per share), compared to $20.8 million ($0.31 per share) in Q1 2025.

Milestone Pharma has only one commercial product segment, Cardamist (Atripamil) for paroxysmal supraventricular tachycardia (PSVT). In Q1 2026 (partial quarter post-launch), product revenue for Cardamist was $0.2 million. As of the end of April 2026, the product has accumulated approximately 600 total prescriptions, with 300 written in the partial Q1 period. The revenue contribution of this segment is 100% of the company's total product revenue for the quarter. The company's other lead candidate Atripamil for atrial fibrillation with rapid ventricular rate (AFib-RVR) is still in clinical development and has not generated revenue.

• Management expects the cash balance of $184 million will provide sufficient runway to fund ongoing Cardamist launch activities and all operations, including execution of the Rivera 301 Phase III trial, into the second half of 2027.
• The Rivera 301 trial is expected to take approximately two years from first patient enrollment to readout, and will enroll up to 600 patients to yield the target of 150-200 evaluable AFib-RVR events. First patient enrollment is guided for the second half of 2026.
• Management expects prescription volume acceleration over the course of the launch, driven by expanding payer coverage, increased promotional frequency from the existing sales force, and positive word-of-mouth from patients who have had successful treatment experiences.
• DTC/direct-to-patient marketing programs are expected to be rolled out gradually, with pilot programs ongoing in 2026 and full deployment expected as late 2026 or early 2027, once sufficient provider awareness and coverage is established.
• Any decision to expand the 60-person sales force will be made later in 2026 or early 2027, based on ROI analysis of existing promotional efforts and patient activation pilots, and aligned with expanded payer coverage.

• Forward-looking statements related to launch progress, clinical trial results, future revenue growth, and coverage expansion are subject to substantial risks and uncertainties that could cause actual results to differ materially from expectations, as detailed in the company's SEC filings including the 2025 Form 10-K.
• Early launch metrics are not definitive, and long-term growth depends on successfully expanding payer coverage beyond the initial Express Scripts win, converting early prescriber interest to repeat and higher-volume prescribing, and successfully completing the AFib-RVR Phase III trial.
• Prescriber adoption could be slowed by administrative hassle related to limited formulary coverage, and the company's current small sales force only reaches one-third of its 10,000 target physicians, limiting near-term growth until coverage and promotional reach expand.

Q: What is the current mix of Cardamist prescribers, how is this mix expected to evolve, and how does the company's patient assistance/free drug program work? / A: Currently, 50% of prescriptions come from general cardiologists, 25% from electrophysiologists (EPs), and 25% from advanced practice providers (APPs) and other providers, matching pre-launch expectations. Over time, general cardiologists will grow as a share of total prescriptions, EPs will remain a smaller but influential segment focused on bridging patients to ablation, and APPs and eventually primary care physicians will grow their prescribing share as adoption becomes more widespread. The company only provides free drug as a bridge when prior authorization or medical exception for coverage is denied, rather than widespread sampling, to help demonstrate patient demand to payers. This program continues to catch patients that would otherwise be denied access, and weekly filled prescription volume growth reflects expanding coverage and effective denial conversion.

Q: What is the expected enrollment timeline and patient population for the Rivera 301 Phase III AFib-RVR trial? / A: The trial targets symptomatic patients with a history of AFib with episodes of rapid ventricular rate (over 100 BPM), who would otherwise need to visit the emergency department for IV treatment. The trial is powered to detect symptomatic improvement, enrolling up to 600 patients to yield 150-200 evaluable events. Management estimates the trial will take approximately two years from first patient enrollment (expected H2 2026) to top-line data, based on experience from the PSVT and AFib Phase II programs.

Q: Does the Express Scripts formulary win accelerate prescription growth, and what are the key levers for long-term launch ramp? / A: The Express Scripts (ESI) win came right at the end of Q1, so it has not yet been fully reflected in Q1 results. ESI coverage reduces administrative hassle for providers and patients, which management expects will directly increase prescription pull-through, and reduces provider frustration that would slow adoption. Long-term ramp drivers include: expanding formulary coverage to additional payers, increasing promotional frequency as the sales force builds relationships with target providers (most have only had 1-2 interactions to date), and growing repeat prescribing as patients with positive experiences request refills and new prescriptions.

Q: How does the company approach DTC spending, and how is the launch tracking relative to pre-launch expectations? / A: DTC/direct-to-patient activation is a core long-term growth driver, but the company is rolling it out gradually to avoid overwhelming providers who are not yet aware of the drug. The company is running small low-cost pilots of patient awareness tactics currently, and will build full direct-to-patient capabilities to launch either late 2026 or early 2027, once sufficient provider awareness and coverage is in place. The launch is tracking ahead of plan: the early ESI formulary win was ahead of expectations, provider engagement is strong with over 10% of reached providers already prescribing within the first 3 months, and early patient feedback is overwhelmingly positive.