Merit Medical has announced positive six-month data from the WAVE trial, evaluating its WRAPSODY endoprosthesis in dialysis patients requiring arteriovenous fistulas (AVF). The results, presented at the Cardiovascular and Interventional Radiological Society of Europe (CIRSE), indicate a significant improvement in target lesion primary patency compared to the standard-of-care percutaneous transluminal angioplasty (PTA).
WAVE Trial Results
The WAVE trial enrolled 245 patients who were randomized to receive either the WRAPSODY stent graft or PTA. The primary outcome measure was target lesion primary patency at six months. Results showed that patients treated with WRAPSODY had an 89.9% patency rate, which was 27 percentage points higher than the PTA cohort.
Mahmood K. Razavi, co-principal investigator in the WAVE trial, stated, "The superiority of the six-month efficacy data is compelling and provides clinicians the chance to evaluate how WRAPSODY can help us prolong the vascular access of our patients. WRAPSODY should be the new standard of care for these patients."
WRAPSODY Design and Function
WRAPSODY is a cell-impermeable stent graft designed to maintain long-term vessel patency in dialysis patients. AVFs are created to provide vascular access for hemodialysis, but repeated procedures can lead to blockages. The WRAPSODY device is constructed with a biocompatible polytetrafluoroethylene layer on the innermost layer to reduce fibrin deposition and thrombus formation. The outer layer is engineered with biocompatible expanded polytetrafluoroethylene, which allows for tissue ingrowth to prevent stent migration. An impermeable middle graft layer is designed to prevent transmural cellular migration.
Prior Clinical Data
Previous results from a 45-patient first-in-human study demonstrated a target lesion primary patency of 100% at 30 days and 84.6% at 365 days, as published in the Journal for Vascular Surgery. Merit Medical is using the WAVE trial results and the first-in-human study to support its Premarket Approval (PMA) application to the FDA for commercial use in the United States.
Context of AVF and Dialysis
Arteriovenous fistulas are crucial for patients undergoing hemodialysis, providing a reliable access point for blood purification. However, these fistulas are prone to stenosis and thrombosis, requiring frequent interventions to maintain patency. The current standard of care, PTA, often results in restenosis, leading to repeated procedures. WRAPSODY offers a potential solution to prolong vascular access and reduce the need for repeat interventions.
The WAVE trial is being conducted under an investigational device exemption granted by the US Food and Drug Administration (FDA).
