Phosphodiesterase type 5 (PDE5) inhibitors are effective in erectile dysfunction (ED) but have several limitations, including a slow onset of action and long half-life.
In a paper in the Journal of Sexual Medicine (online, 3 January 2018), researchers explored the potential of a topical, rapidly absorbed gel containing glyceryl trinitrate, which is under development for use in ED, in a phase II crossover trial
. They randomly assigned 232 men to active treatment or placebo for four weeks, followed by a 1-week washout period, before switching treatment sequence for another four weeks.
The researchers found that International Index of Erectile Function (IIEF) domain scores rose, from a mean baseline score of 17.1 to 19.6 after active treatment, compared with 18.5 after placebo. The effect was most pronounced in patients with mild ED, while results in those with moderate or severe ED were not significant.
The team said that the results indicated potential for the glyceryl trinitrate gel in ED but future studies should explore higher doses, particularly in moderate and severe ED.