Safety and Efficacy Study Using Gene Therapy for Critical Limb Ischemia

In the absence of revascularization options, most patients with CLI require amputation within 6 months. Patients requiring major amputation face a diminished quality of life, an unfavorable natural history and need extensive resources for their post-amputation rehabilitation and course. The 1-year amputation-free survival rate for patients diagnosed with CLI is 45%; the mortality rate is approximately 25% and may be as high as 45% in those who have undergone amputation. Management of this end-stage disease process consumes a significant amount of healthcare resources. Clearly, new therapeutic approaches are required. Hepatocyte growth factor (HGF) has been shown to be a potent angiogenic growth factor stimulating the growth of endothelial cells and migration of vascular smooth muscle cells. Because of its pluripotent capabilities, increasing the availability of HGF in ischemic tissues to achieve therapeutic angiogenesis has been a growing area of research. This study will use VM202, which is a DNA plasmid that contains novel genomic cDNA hybrid human HGF coding sequence (HGF-X7) expressing two isoforms of HGF, HGF 728 and HGF 723. As there are currently no approved drugs that can reverse CLI and as most patients have exhausted surgical and endovascular intervention options, inducing angiogenesis in the affected limb with VM202 may result in an increase in tissue perfusion, which, in turn improve wound healing, reduce pain and improve limb salvage rates.