AB045. Novel gene therapy for erectile dysfunction

OBJECTIVE: Erectile dysfunction (ED) is a major health problem that affects millions of men all around the world. Since a significant number of ED patients have a poor response to the first line oral phosphodiesterase 5 inhibitors, underlying treatment like gene therapy is needed to evolve as a promising solution. METHODS: Basic and clinical researches regarding the application of gene therapy for ED over this few decades were reviewed. Then we summarize the state-of-the-art development of therapeutic targets, transfection methods, model systems and their efficacy in this field. RESULTS: All gene therapy studies are still in preclinical phase except one clinical trial using the target of Ca(2+)-activated, large-conductance K(+) channel. In basic researches, animal models of ED induced by aging, diabetes, cavernous nerve injury, hypertension, hypercholesterolemia have been utilized to evaluate the capacities and mechanisms of therapeutic targets to improve ED. In addition to the classic transfection methods like naked plasmid DNA, liposome and virus, new gene therapy vectors such as stem cells come into stage and present specific advantages. Besides, novel systems are invented to optimize the process of transfection. These researches demonstrate that current selected targets are widely involved in multiple erection related signaling pathways and all of them present exciting results. Although it is still in the stage of phase I, the clinical trial also reveals promising efficacy and primary safety. CONCLUSIONS: More clinical trials are needed for potential targets to confirm their effects on ED patients. Although there is a long way to go before clinical application, gene therapy is an inspiring future treatment option for ED.