Terumo Neuro Announces Publication of Landmark RAGE Study Results for Hydrogel Embolic System Coils for Ruptured Intracranial Aneurysms

Largest prospective, core lab–adjudicated trial in North America confirms strong occlusion, low rebleeding, and favorable functional independence

Aliso Viejo, CA – May 13, 2026 – Terumo Neuro, a global leader in neurovascular innovation and a wholly owned subsidiary of Terumo Corporation, today announced the publication of results from the RAGE¹ (Ruptured Aneurysms Treated with Hydrogel Coils) study in the Journal of NeuroInterventional Surgery (JNIS). RAGE is the largest prospective, core laboratory–adjudicated, externally monitored trial of endovascular coil embolization for ruptured intracranial aneurysms conducted in North America, providing robust contemporary evidence supporting the safety and effectiveness of 2nd generation Hydrogel Embolic System (HES) coils in clinical practice.

The multicenter, nonrandomized study enrolled more than 750 adult patients across 45 North American sites, with 100% ruptured, saccular intracranial aneurysms, reflecting real world treatment using current techniques and strategies. The trial delivers high quality, peer reviewed data with sufficient scale to support meaningful subset analyses and evaluation of key variables impacting effectiveness, safety, and durability of endovascular coiling in this high-risk patient population.

“The publication of the RAGE study represents another important benchmark for endovascular aneurysm treatment. It builds upon other high-quality studies, like GREAT and HEAT, which have consistently demonstrated the continual evolution in the safety and effectiveness of coil embolization for the treatment of ruptured cerebral aneurysms with the HES system,” said Dr. David Fiorella, Director of the Cerebrovascular Center at Stony Brook Medicine. “Over the years we have appreciated progressively improved clinical and angiographic outcomes for these patients with increasing occlusion rates and durability as well as exceedingly low re-rupture rates.”

Each year, approximately 30,000 people in the United States experience a ruptured brain aneurysm—an event that occurs every 18 minutes. Ruptured brain aneurysms are fatal in about 50% of cases, and among those who survive, roughly 66% suffer a permanent neurological deficit. These sobering statistics underscore the urgent need for continued advances in diagnosis and treatment and are consistent with data shared by the Brain Aneurysm Foundation, a leading nonprofit organization dedicated to brain aneurysm awareness, education, and research.

Compelling Clinical Outcomes at Scale RAGE met its primary effectiveness and safety objectives, demonstrating outcomes that compare favorably with historical benchmarks for bare platinum coil embolization in ruptured aneurysms. Key findings include:

• Adequate occlusion rate of 86%, statistically superior to the 80.4% performance goal established by the CLARITY² study of bare platinum coils (p=0.0004).

• Exceptionally low aneurysm rebleeding rate of 0.5%, compared with approximately 1% per year reported in the CARAT¹ study and a 2.4% early rebleeding rate observed in ISAT^4-7.

• Strong functional independence, with 88% of patients achieving a modified Rankin Scale (mRS) score ≤2, favorably compared with outcomes reported in CLARITY² and ISAT^4-7.

These results reinforce the role of Hydrogel coils as a safe and durable embolization solution in the acute management of ruptured intracranial aneurysms, a condition associated with significant morbidity and mortality.

Advancing Evidence‑Based Neurovascular Care Ruptured cerebral aneurysms remain a leading cause of subarachnoid hemorrhage, affecting tens of thousands of patients annually in the United States alone, with substantial global mortality. Against this backdrop, the RAGE study provides timely, practice‑relevant evidence supporting innovation that improves patient outcomes in a life‑threatening condition.

“Terumo Neuro is committed to advancing clinically meaningful solutions grounded in rigorous evidence,” said Nagesh Uppuluri, SVP, Global Clinical & Medical Affairs, Terumo Neuro. “The publication of RAGE in JNIS underscores our long‑term investment in large‑scale, high‑quality clinical research and our partnership with leading investigators to address some of the most challenging conditions in neurovascular care.”

As the largest prospective study of its kind in ruptured aneurysms in North America, RAGE establishes a new benchmark for evidence quality in neurointerventional research. By combining external monitoring, independent core laboratory adjudication, and contemporary treatment practices, the study equips neurointerventionalists with credible data they can trust, understand, and cite when making critical treatment decisions.

The full RAGE study results are now available in the Journal of NeuroInterventional Surgery

For more information, contact:
Rebecca Janzon, Terumo Neuro
Email: Rebecca.janzon@microvention.com

About Terumo Neuro
We’re in business to create and deliver innovations that redefine what’s possible in neurovascular treatment, meaningfully advancing both physician practice and patient outcomes. Founded in 1997 as MicroVention and acquired by Terumo Corporation in 2006, Terumo Neuro offers more than thirty products for the treatment of cerebral aneurysms, ischemic stroke, carotid artery disease, and neurovascular malformations. Headquartered in Aliso Viejo, California, Terumo Neuro products are sold in more than seventy countries through a dedicated sales organization as well as strategic distribution partnerships. Manufacturing facilities are in Aliso Viejo, California, and San José, Costa Rica.

For more information, please visit www.terumoneuro.com.

About Terumo Corporation
Terumo (TSE:4543) is a global leader in medical technology and has been committed to "Contributing to Society through Healthcare" for more than 100 years. Based in Tokyo and operating globally, Terumo employs over 30,000 associates worldwide to provide innovative medical solutions in more than 160 countries and regions. The company began as a Japanese thermometer manufacturer and now offers an extensive portfolio—from vascular intervention and cardio-surgical solutions to blood transfusion, cell therapy technology, and essential clinical products.

INDICATIONS FOR USE / INTENDED PURPOSE:
The HydroCoil™ Embolic System (HES) is intended for the endovascular embolization of intracranial aneurysms and other neurovascular abnormalities such as arteriovenous malformations and arteriovenous fistulae. The HES is also intended for vascular occlusion of blood vessels within the neurovascular system to permanently obstruct blood flow to an aneurysm or other vascular malformation and for arterial and venous embolizations in the peripheral vasculature. The device should only be used by physicians who have undergone pre-clinical training in all aspects of HES procedures as prescribed by Terumo Neuro.

RX Only: Federal (USA) law restricts this device to sale by or on the order of a physician.

For Healthcare Professional Use Only. Please refer to IFU for the full list of risks, contraindications, warnings, and precautions.

HYDROCOIL™ is a trademark of MicroVention, Inc. registered in the United States and other jurisdictions. All brand names are trademarks or registered trademarks owned by TERUMO CORPORATION, its affiliates, or unrelated third parties. All third-party products are trademarks™ or registered® trademarks and remain the property of their respective holders.

Please refer to the IFU for the full list of risks, contraindications, warnings and precautions.
CE 0297, class III Legal Manufacturer: MicroVention, Inc, dba Terumo Neuro.

Clinical References

1. Fiorella D., Toth G., White T.G. et al. Final results of the Ruptured Aneurysms Treated with Hydrogel Coils (RAGE) study: a multicenter study of 771 patients. J NeuroIntervent Surg 2026; published online 2 April 2026; DOI: 10.1136/jnis-2026-025097.

2. Pierot L, Cognard C, Anxionnat R, et al. Endovascular treatment of ruptured intracranial aneurysms: factors affecting midterm quality anatomic results: analysis in a prospective, multicenter series of patients (CLARITY). AJNR Am J Neuroradiol 2012;33:1475–80.

3. S. Claiborne Johnston, MD, PhD; Christopher F. Dowd, MD; et al.Predictors of Rehemorrhage After Treatment of Ruptured Intracranial Aneurysms, The Cerebral Aneurysm Rerupture After Treatment (CARAT) Study. Stroke 2008.

4. Molyneux A, Kerr R, Stratton I, et al. International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomized trial. Lancet 2002;360:1267–74.

5. Molyneux AJ, Birks J, Clarke A, et al. The durability of endovascular coiling versus neurosurgical clipping of ruptured cerebral aneurysms: 18-year follow-up of the UK cohort of the International Subarachnoid Aneurysm Trial (ISAT). Lancet 2015;385:691–7.

6. Molyneux AJ, Kerr RSC, Birks J, et al. Risk of recurrent subarachnoid hemorrhage, death, or dependence and standardized mortality ratios after clipping or coiling of an intracranial aneurysm in the International Subarachnoid Aneurysm Trial (ISAT): long-term follow-up. Lancet Neurol 2009;8:427–33.

7. Molyneux AJ, Kerr RSC, Yu L-M, et al. International subarachnoid aneurysm trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomized comparison of effects on survival, dependency, seizures, rebleeding, subgroups, and aneurysm occlusion. Lancet 2005;366:809–17.