LB04 - Two-year outcomes on proximal neck dynamics and aneurysm growth from a First in Human study evaluating a novel AAA medical therapy

Objectives: Approximately 200,000 abdominal aortic aneurysms (AAAs) are diagnosed each year in the US, the majority (~90%) below the threshold for repair. A medical or interventional treatment that can reliably slow or halt the growth of sub-threshold AAAs has proven elusive. A First in Human (FIH) trial evaluated safety and potential efficacy of a local, single-dose endovascular delivery of 1,2,3,4,6-pentagalloylglucose (PGG) to treat small to medium-sized AAAs. Approximately 200,000 new abdominal aortic aneurysms (AAAs) are diagnosed each year in the US, the majority (~90%) below the threshold for repair ( < 5.5 cm in men; < 5.0 cm in women). A medical or interventional treatment that can reliably slow or halt the growth of sub-threshold AAAs has proven elusive. A First in Human (FIH) trial evaluated safety and potential efficacy of a local, single-dose endovascular delivery of 1,2,3,4,6-pentagalloylglucose (PGG) to treat small to medium-sized AAAs.

Methods: The FIH trial was a single arm, open-label study enrolling 46 patients with small to medium-sized infrarenal AAAs. PGG was administered directly into the AAA followed by core lab computed tomography angiography (CTA) imaging annually. To date, full cohort 1- and 2-year follow-up is available. Linear regression analysis of AAA growth rates and proximal neck characteristics were assessed.

Results: Forty-one (41/46) patients completed 2-year follow-up from 6 international sites; 38 men and 3 women with median age of 70 years (IQR 65-76). Median baseline maximum AAA diameter was 4.4 cm (IQR 3.9-4.6). Through 2-year follow-up, annual maximum diameter AAA growth rate was a median of 0.10 cm/y (IQR range, 0.14). In nonclinical studies, PGG was shown to diffuse rapidly through aortic tissue impacting tissue adjacent to the AAA. Proximal neck median baseline diameter was 2.1 cm (IQR range, 0.32) with two year median growth rate of 0.0 cm/y (IQR range, 0.05). Additional proximal neck data such as change in length, morphology, and thrombus burden will be included at the time of SVS VAM LBCT presentation. Growth rates will be compared to data from recent AAA clinical studies on similar patient cohorts.

Conclusions: Data from this FIH study suggest a local, single-dose intravascular treatment of PGG to small to medium-sized AAAs may strengthen aortic tissue and reduce dilatation of both AAA tissue and the adjacent proximal neck. These changes have the potential to prevent or delay the need for AAA repair in many patients and may improve outcomes of AAA repair for those patients that eventually need further intervention.