Therapeutic Arteriogenesis/Angiogenesis for Peripheral Arterial Disease by Nanoparticle-Mediated Delivery of Pitavastatin into Vascular Endothelial Cells

Two decades have passed since therapeutic angiogenesis was proposed to promote reparative collateral growth as an alternative therapy for ischemic diseases in patients for whom neither surgical revascularization nor endovascular therapy was suitable. When therapeutic angiogenesis first began, local administration was conducted using recombinant growth factor proteins or gene-encoding growth factors for endothelial cells. Since then, autologous stem cells and endothelial progenitor cell transplantation therapy have been developed. Although many clinical trials have been performed on patients, most therapies have not yet become standard treatments. We have developed a nanoparticle (NP)-mediated, drug-targeting delivery system using bioabsorbable poly-lactic/glycolic acid (PLGA) NPs. In several animal models, pitavastatin-incorporated (Pitava)-NPs showed significant therapeutic effects on critical limb ischemia. Because PLGA NPs are delivered selectively to vascular endothelial cells after intramuscular administration, it is suggested that therapeutic angiogenesis/arteriogenesis plays an important role in the mechanism by which Pitava-NPs exert beneficial therapeutic effects. To translate this to clinical medicine, we have performed studies and produced Pitava-NPs in compliance with good laboratory practice/good manufacturing practice regulations, and completed a phase I/II clinical trial, reporting the safety and efficacy of Pitava-NP intramuscular injection for patients with critical limb ischemia. This review will focus on therapeutic angiogenesis/arteriogenesis for peripheral arterial disease induced by Pitava-NPs.