Terumo Neuro’s HydroCoil Embolic System to Treat Ruptured Intracranial Aneurysms Studied in RAGE

May 27, 2026—Terumo Neuro, a wholly owned subsidiary of Terumo Corporation, announced the publication of results from the RAGE study of ruptured aneurysms treated with hydrogel coils.

According to Terumo Neuro, RAGE met its primary effectiveness and safety objectives for the company’s second-generation HydroCoil embolic system for endovascular coil embolization to treat ruptured intracranial aneurysm in clinical practice, comparing favorably with historical benchmarks for bare platinum coil embolization.

RAGE is a prospective, core laboratory-adjudicated, externally monitored trial. The multicenter, nonrandomized study enrolled more than 750 adult patients across 45 sites in North America. The enrolled patients had 100% ruptured, saccular intracranial aneurysms, reflecting real-world treatment using current techniques and strategies, noted the company.

As summarized in Terumo Neuro’s press release, key findings from RAGE include the following:

• An occlusion rate of 86%, which is statistically superior to the 80.4% performance goal established by the CLARITY study of bare platinum coils (P = .0004).
• An aneurysm rebleeding rate of 0.5%, compared with approximately 1% per year reported in the CARAT study and a 2.4% early rebleeding rate observed in ISAT.
• Functional independence, with 88% of patients achieving a modified Rankin Scale score ≤ 2, favorably compared with outcomes reported in CLARITY and ISAT.

These results reinforce the role of hydrogel coils as a safe and durable embolization solution in the acute management of ruptured intracranial aneurysms, stated the company.

The RAGE study results were published by David Fiorella, MD, et al in the Journal of NeuroInterventional Surgery. Dr. Fiorella, who is Director of the Cerebrovascular Center at Stony Brook Medicine in Stony Brook, New York, commented on the findings in Terumo Neuro’s press release.

“The publication of the RAGE study represents another important benchmark for endovascular aneurysm treatment,” stated Dr. Fiorella. “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 HydroCoil embolic system.

“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 rerupture rates.”