8-K: Adagio Medical's VT Study Shows High Acute Effectiveness

Adagio Medical announced preliminary acute safety and efficacy results from its FULCRUM-VT Study for treating Sustained Monomorphic Ventricular Tachycardia, demonstrating 97% acute effectiveness.

Summary

• Adagio Medical Holdings, Inc. announced preliminary acute (within 7 days) safety and efficacy results from its FULCRUM-VT Study.
• The study evaluates Ultralow Temperature Cryoablation (ULTC) technology for Sustained Monomorphic Ventricular Tachycardia (SMVT) in patients with both ischemic and non-ischemic cardiomyopathy.
• Data was presented by Travis Richardson, MD, at the 20th Annual International Symposium on Ventricular Arrhythmias held in Philadelphia on October 10, 2025.
• A total of 207 patients underwent ventricular tachycardia (VT) ablation using Adagio's ULTC system at 19 sites in the United States and Canada.
• Acute clinical success, defined as non-inducibility of target ventricular arrhythmias, was 97.4%.
• All clinically-relevant ventricular tachycardias were eliminated in 96.7% of patients tested by post-ablation programmed electrical stimulation.
• The mean procedure duration was 206 +/68 minutes.
• The patient population included those with a Left Ventricular Ejection Fraction (LVEF) of 35+/-10%, with 33% having non-ischemic cardiomyopathy (NICM) and 75% with congestive heart failure.

Sentiment

Score: 8

Explanation: The preliminary acute results show very high efficacy (97.4% acute success) and a favorable safety profile for a challenging patient population, indicating strong potential for the ULTC technology. While there were peri-procedural deaths, the overall safety rate and the fact that only one was definitely device-related, combined with the high efficacy, suggest a positive outlook for the technology's development and regulatory path.

Positives

• Acute clinical success, defined as non-inducibility of target ventricular arrhythmias, was 97.4%.
• All clinically-relevant ventricular tachycardias were eliminated in 96.7% of patients tested by post-ablation programmed electrical stimulation.
• The study demonstrated a favorable safety profile with a low rate of intraand peri-procedural complications, consistent with the underlying morbidity of the treated population.
• The ULTC system's ability to produce deep, titratable endocardial lesions without irrigation and without concerns for catheter stability makes it a promising tool for a broad patient population.
• The broad inclusion criteria for the study, including patients with non-ischemic disease (often more difficult to treat), fueled swift enrollment and showed excellent acute effectiveness across the study population.
• No signal of incremental risk was associated with the specific technology/novel energy source.

Negatives

• A 2.5% rate of major adverse events was observed.
• Four (1.9%) peri-procedural deaths occurred.
• One (0.5%) peri-procedural death was adjudicated by an independent clinical events committee as definitely related to the investigational device (sepsis post-surgery in a roll-in patient).
• Other deaths included hypoxic failure after surgical RV laceration and acute decompensation post-anesthesia.
• One air embolism during sheath exchange (roll-in patient) was also reported as a major adverse event.

Risks

• The reproducibility of any favorable results initially seen in the preliminary FULCRUM-VT acute data.
• The ability of the proprietary ULTC system to become a tool for a broad patient population.
• Adagio's research, development, and regulatory plans for its product candidates.
• The ability of Adagio's proprietary ULTC technology to transform treatment for patients with VT.
• General business risks are described in Adagio's Securities and Exchange Commission (SEC) filings, including its Annual Report on Form 10-K for the full-year ended December 31, 2024, and Quarterly Report on Form 10-Q for the quarter ended June 30, 2025.

Future Outlook

The company plans to share the six-month primary efficacy endpoint results of the FULCRUM-VT trial at the Heart Rhythm 2026 conference. Long-term outcomes, as well as analysis of the effectiveness in different myocardial substrates, will be reported in the future. The results of the study will be used to apply for FDA premarket approval (PMA) for Adagio's vCLAS Cryoablation System, potentially leading to the broadest industry indication for purely endocardial ablation of scar-mediated VT. Development of a next-generation catheter design (8.5Fr, D/F, more flexible, colder and shorter ablations) is underway.

Management Comments

• Dr. Travis Richardson: "The patient profile in FULCRUM-VT is representative of what we see in real-world practice. The ability of Adagio's ULTC system to produce deep, titratable endocardial lesions without irrigation and without concerns for catheter stability make it a promising tool for a broad patient population. These factors, along with the broad inclusion criteria for the study, fueled swift enrollment."
• Dr. Travis Richardson: "FULCRUM-VT not only included patients with ischemic myopathy, but also a large number with nonischemic disease, whose VT is often more difficult to treat due to deep substrate. Despite this, the acute effectiveness across the study population was excellent. This, along with the favorable safety profile of the ULTC System, is encouraging. VT is a largely undertreated condition, partially because the available treatment tools make ablation procedures challenging, and I have hope that ULTC will help to change that."
• Todd Usen, Chief Executive Officer of Adagio Medical: "We are pleased with the preliminary FULCRUM-VT acute data, which highlight the potential of Adagio's proprietary ULTC technology to transform treatment for patients with ventricular tachycardia."
• Todd Usen, Chief Executive Officer of Adagio Medical: "On behalf of the entire Adagio Medical team, I want to thank all of the investigators, research coordinators and patients who have supported this study and whose commitment to serving this underserved population of patients will bring us one step closer to a purpose-built solution for VT."

Industry Context

Ventricular Tachycardia (VT) is described as a largely undertreated condition, partly due to the challenges posed by existing treatment tools. Adagio's Ultralow Temperature Cryoablation (ULTC) system aims to address this by offering a promising tool for a broad patient population, including those with difficult-to-treat non-ischemic disease. The technology's ability to create deep, titratable lesions without irrigation and with catheter stability could represent a significant advancement in the catheter ablation market for cardiac arrhythmias, potentially improving patient outcomes and expanding treatment access.

Comparison to Industry Standards

• Traditional (N20-base, Tb=-88.50C) cryoablation technology is useful in certain clinical scenarios but lacks power and lesion depth advantage over radiofrequency (RF) ablation, whereas Adagio's ULTC operates near-critical (NC)-N2, offering deeper, titratable lesions.
• Adagio's vCLAS Cryoablation System is commercially available for the treatment of monomorphic ventricular tachycardia in Europe and select other geographies, indicating it has met regulatory standards in those regions.
• The FULCRUM-VT study results will be used to apply for FDA premarket approval (PMA), potentially leading to the broadest industry indication for purely endocardial ablation of scar-mediated VT, setting a new benchmark for treatment options.

Stakeholder Impact

• Shareholders: Positive impact due to strong preliminary clinical trial results, potentially leading to FDA approval and broader market adoption, which could enhance company valuation.
• Patients: Potential for a new, highly effective treatment option for Sustained Monomorphic Ventricular Tachycardia, especially for those with difficult-to-treat conditions, offering improved quality of life.
• Medical Professionals: Provides a promising new tool for VT ablation, potentially simplifying procedures, improving outcomes, and expanding the treatable patient population.

Next Steps

• Share six-month primary efficacy endpoint results of the FULCRUM-VT trial at the Heart Rhythm 2026 conference.
• Report long-term outcomes and analysis of effectiveness in different myocardial substrates in the future.
• Apply for FDA premarket approval (PMA) for Adagio's vCLAS Cryoablation System based on study results.
• Continue development of next-generation catheter design (8.5Fr, D/F, more flexible, colder and shorter ablations).

Key Dates

Recommendation

The preliminary acute results from the FULCRUM-VT study are exceptionally strong, demonstrating 97.4% acute effectiveness and 96.7% patient-level clinical success in a challenging patient population. While there were some adverse events, including deaths, the overall safety profile is deemed favorable, and only one death was definitively linked to the device. This high efficacy, coupled with the potential for FDA PMA and a broad industry indication, positions Adagio Medical's ULTC technology as a significant advancement in treating ventricular tachycardia. The positive clinical data significantly de-risks the product's future and suggests substantial market potential, warranting a strong buy recommendation for long-term investors.

Keywords

Adagio Medical, ADGM, FULCRUM-VT Study, Ultralow Temperature Cryoablation, ULTC, Ventricular Tachycardia, VT ablation, SMVT, cardiac arrhythmias, medical device, electrophysiology, clinical trial, FDA PMA, vCLAS Cryoablation System