Preparation and clinical evaluation of nano-transferosomes for treatment of erectile dysfunction

OBJECTIVE: The goal of the present study was to formulate topical nanocarriers of the low-cost vasodilator, papaverine hydrochloride (PH), as an alternative to the painful penile injections. The injections are used for both diagnosis and treatment of erectile dysfunction. Transdermal nano-transferosome (T), the ultraflexible nanoliposome, was used as a nanocarrier to enhance the penetration of the papaverine to the penis. METHODS: Different nano formulas were prepared and characterized for their encapsulation efficiency, particle size, zeta potential, and cumulative drug release. The formula acquired the best characteristics was incorporated into 2% (w/v) hydroxypropyl methylcellulose hydrogel base. The gel containing transferosomal papaverine hydrochloride (PH) and that containing free PH were clinically compared using color flow Doppler measurements. RESULTS: The results revealed that transferosome 3 (T3) had the highest entrapment efficiency approaching 72%, low particle size of 220 nm, and zeta potential of −33.4 mV. The formula released 73% of its initial drug content within 2 hours. The clinical evaluation showed the increase in the cavernous artery diameter from 0.53 mm to 0.78 mm and the increase in the peak systolic flow velocity from 5.95 cm/second to 12.2 cm/second, both of which were found to be significant at P<0.05. CONCLUSION: It is evident from the study that the transferosomes can be used as a carrier of papaverine hydrochloride for both diagnosis and treatment of the erectile dysfunction. This new strategy could be used successfully in the treatment of erectile dysfunction and in male impotency.