VATRIX MEDICAL, INC.
Abdominal aortic aneurysms (AAAs) are associated with impaired arterial wall integrity, leading to
abnormal ballooning and eventual fatal rupture. Currently the sole treatment for such aneurysms is surgical
intervention. Surgical procedures entail either endovascular stent graft repair or complete replacement of the
diseased arterial segment with an artificial vascular graft. Although often effective, endovascular stents are
anatomically appropriate for only 30% to 60% of AAA patients at the outset and present the risk of endoleaks
and graft displacement. Moreover, open surgery for full size graft insertion is highly invasive, making it
inappropriate for patients with high operative risk. The drawbacks associated with these procedures are
significant enough that they are only applied to those patients with late-stage, critical aneurysms. Treatment
options are particularly limited (virtually non-existent) for patients with small or moderate aneurysms, which
comprise the largest percentage of all aneurysm patients. Consequently, novel therapeutic approaches
targeted at hindering the progression of aneurysms promptly after diagnosis would be extremely beneficial. By
halting the aneurysm-related expansion or growth, the risk of rupture could be significantly decreased.
In addition to arterial dilatation, the onset and progression of AAAs are associated with enzymatic
degradation of extracellular matrix components such as elastin. Phenolic tannins, such as penta-galloylglucose
(PGG), bind to vascular elastin, and in doing so, render elastin highly resistant to enzymatic degeneration while
also making the tissue mechanically stronger. These unique properties provide a platform for the potential
development of novel, safe, and effective treatments for all AAAs. In previous studies, we have shown that
PGG binds to aortic tissue, protects extracellular matrix proteins such as elastin, mechanically strengthens the
tissue, and is effective in stopping aneurysm growth/development in a widely accepted animal model.
This proposal describes the development of endovascular tools to deliver this treatment locally to the
site of aneurysm (from inside the blood vessel). For the work proposed here, we will evaluate the ability of our
devices to deliver the aforementioned stabilizing agents to an isolated area of aortic aneurysmal disease. The
tools and delivery procedure will be carried out in an endovascular and minimally invasive fashion. Evaluation
of three distinct device prototypes will initially be performed in vitro with physiologically relevant silicon models.
Upon selection of the superior device prototype, this particular design will also be evaluated in vivo. For these
studies, the device will be deployed to isolate a region of porcine infrarenal abdominal aorta, allowing PGG to
be delivered to this specific region. Subsequent analysis will evaluate the binding of PGG to the local aortic
wall, and its effect on this tissue.