Shape Memory Medical recently announced that it has completed enrolment in the AAA‑SHAPE pivotal trial. This is a prospective, multicentre, randomised, open‑label controlled study evaluating the safety and effectiveness of the Impede‑FX RapidFill device when used alongside endovascular aneurysm repair (EVAR) to improve abdominal aortic aneurysm (AAA) sac behaviour.
AAA-SHAPE randomised 180 patients at 48 centers across the USA, Europe, and New Zealand in a 2:1 ratio to receive either EVAR plus sac management with Impede-FX RapidFill or standard EVAR alone. Participants will be followed for five years. Primary endpoints include 30-day freedom from major adverse events, aneurysm rupture, perforation, and conversion to open repair, as well as the proportion of patients achieving ≥10% aneurysm sac volume reduction without AAA-related intervention through one year.
The final participant was enrolled at Mayo Clinic in Rochester, USA, where Randall DeMartino is the principal investigator.
“AAA-SHAPE addresses an important question in EVAR: whether managing the aneurysm sac at the time of EVAR can improve sac regression,” said Marc Schermerhorn (Beth Israel Deaconess Medical Center, Boston, USA), global principal investigator for AAA-SHAPE. “Sac behaviour after EVAR is closely linked to long-term outcomes, yet no randomised controlled trial has evaluated a dedicated sac management strategy against standard EVAR alone. This study is designed to provide the evidence needed to answer that question.”
The investigational Impede‑FX RapidFill device incorporates Shape Memory Medical’s novel shape memory polymer technology. Delivered through a catheter, the device expands when exposed to blood and creates a radiolucent, porous scaffold designed to fill the space around an EVAR stent graft. In AAA-SHAPE, it is intended to promote clot formation within the aneurysm sac and support sac shrinkage over time.
“EVAR remains the gold standard repair for AAA, but it does not directly treat the aneurysm sac,” said Virendra Patel (New York-Presbyterian/Columbia University Irving Medical Center, New York, USA), global co-principal investigator for AAA-SHAPE. “We now recognise that lack of sac regression may be associated with increased long-term risk, including reintervention, rupture, and mortality. AAA-SHAPE is the first randomised trial designed to determine whether proactive sac management can improve those outcomes.”
Before the AAA-SHAPE pivotal trial, the AAA-SHAPE early feasibility studies enrolled 35 patients across sites in New Zealand and the Netherlands. Three-year follow-up data are expected to provide additional insight into the long-term performance of the investigational device and its potential role in promoting aneurysm sac shrinkage after EVAR.
