Is gene therapy for limb ischemia a reality?

The concept of angiogenic therapy emerged in the early 1990s. The method employs genes that encode growth factors to promote formation of new vessels and remodeling of collateral vessels. Since the procedure involved in this therapy usually only consists of local injections of vectors, the process is minimally invasive, quick, and simple to perform. However, since the first clinical evidence of the effects of gene therapy with vascular endothelial growth factor (VEGF) was observed in patients with peripheral artery disease, to date only two angiogenic therapy drugs have been approved, one in Russia and another in Japan, which seem a very small number, in view of the large volume of investment made in pre-clinical and clinical studies. After all, can we conclude that angiogenic therapy is a reality?