Jupiter Endovascular Announces Positive Results From SPIRARE II Pivotal Trial

Jupiter Endovascular Inc. said the SPIRARE II pivotal trial evaluating the use of its Vertex Pulmonary Embolectomy System in patients with acute, intermediate-risk pulmonary embolism (PE) met both primary endpoints, demonstrating meaningful heart recovery and clinical safety.

“Pulmonary embolism is fundamentally a cardiovascular disease, where restoration of hemodynamic stability, beyond simple clot removal, is the key determinant of patient recovery,” said Sameh Sayfo, M.D., pulmonary embolism response team director at Baylor Scott & White The Heart Hospital – Plano and SPIRARE II global co-principal investigator. “Historically, the ability to achieve both safe right-heart navigation and the procedural stability necessary for controlled PE thrombectomy has represented a significant limitation in consistently normalizing hemodynamics. What makes SPIRARE II particularly compelling is the opportunity to evaluate a system that may enhance not only clot extraction, but also the overall quality, precision, and physiologic impact of the intervention.”

The Vertex system leverages the company’s patented Transforming Fixation (TFX) platform technology in a catheter system designed to navigate flexibly through the right heart and then stabilize on-demand in the pulmonary arteries for precise intervention. The ability for one device to provide both flexible navigation and stable support is intended to address long-standing challenges in PE thrombectomy related to cardiac strain and reliable vessel access within the pulmonary vasculature.

SPIRARE II is a prospective, single-arm, multicenter pivotal study that enrolled 123 patients across 19 sites in Europe and the United States. The trial evaluated the safety, right heart functional improvement, and clinical outcomes of PE treatment with the Vertex system.

The trial met both primary endpoints:

• 0.39 mean reduction in RV/LV ratio at 48 hours (95% CI: 0.33, 0.45)
• 2.4% major adverse event (MAE) rate (3/123, p<0.0001)

TFX-enabled thrombectomy achieved meaningful afterload reduction and right heart recovery beyond clot extraction, as demonstrated by paired invasive hemodynamic measurements:

• 29% reduction in mean pulmonary artery pressure (mPAP)
• 29% reduction in systolic pulmonary artery pressure (sPAP)
• 26% reduction in total pulmonary vascular resistance (TPVR)

The trial achieved 100% technical success with zero use of adjunctive thrombolytics, and treatment characteristics demonstrated an efficient and minimally invasive procedure:

• 83% of cases did not require re-crossing of the pulmonic valve
• 39% of cases did not require use of a super-stiff guidewire
• 40.2 minute mean procedure time (±16.4 min)

“The SPIRARE II results are especially impressive, recognizing the hemodynamic severity of the patient population—54% presented with normotensive shock and 93% were classified in C3 or D2 risk categories under the 2026 ACC/AHA PE guidelines,” noted Catalin Toma, M.D., director of Interventional Cardiology at the UPMC Heart and Vascular Institute and SPIRARE II global co-principal investigator. “TFX-enabled thrombectomy delivered consistent, reproducible recovery across all patient classifications, which we believe was achieved by having stable, controlled access to target vessel obstructions. Future post-hoc analyses will help us better understand the relationship between vessel access and the depth of physiologic recovery we observed. We believe these findings will meaningfully inform the approach to PE intervention moving forward.”

The Vertex Pulmonary Embolectomy System leverages Jupiter Endovascular’s proprietary Transforming Fixation (TFX) platform technology to navigate flexibly through the right heart and transform into a stabilized state in the pulmonary arteries for precise, controlled intervention. TFX’s capability to decouple flexible navigation from stable support addresses long-standing challenges in PE thrombectomy related to cardiac strain, guidewire reliance, and reliable vessel access—enabling the system to achieve afterload relief and hemodynamic recovery alongside clot removal.

“SPIRARE II was designed not only to support regulatory clearance, but also to generate a robust clinical dataset that includes paired invasive hemodynamics and detailed patient-level data across a population of elevated severity,” Jupiter Endovascular CEO Carl J. St. Bernard stated. “We believe these findings will contribute to a growing understanding of pulmonary embolism as a complex cardiovascular disease centered on right heart dysfunction and hemodynamic compromise, not defined by clot burden alone. We are deeply grateful to the patients, investigators, and clinical teams who participated in SPIRARE II and helped advance the field toward a more sophisticated approach to PE care. As we move toward commercialization, we see a significant opportunity to apply our TFX platform technology across other complex cardiovascular anatomies where stable access and controlled intervention remain major unmet needs.”

Jupiter Endovascular Inc. is a Menlo Park, Calif.-based medical technology company developing a new class of endovascular interventions using its proprietary Transforming Fixation (TFX) technology. The company’s lead program, the Vertex Pulmonary Embolectomy System, is designed to provide physicians with on-demand stability and control during transcatheter intervention in the pulmonary vasculature. The Vertex Pulmonary Embolectomy System is investigational and not approved for commercial use in the United States or Europe.