Oral treatment of erectile dysfunction with apomorphine SL.

Apomorphine SL (Ixense, Uprima) is a new oral medication shown to be effective in the treatment of erectile dysfunction. This compound is a dopaminergic agonist with affinity for dopamine receptor sites - mostly D(2) - within the brain known to be involved in sexual function. Apomorphine induces selective activation in the nucleus paraventricularis leading to erectogenic signals. More than 5,000 men with erectile dysfunction participated in phase II/III clinical trials assessing the safety and efficacy of doses ranging from 2 to 6 mg. The most favorable risk/benefit ratio is seen with a dose-optimization regimen of 2-3 mg: the 3-mg dose provides efficacy comparable to that of 4 mg but with fewer side effects. Consequently, review of clinical studies focuses on data with the 2- to 3-mg dose, the registered dose for use in clinical practice. The primary efficacy endpoint in most clinical trials with apomorphine SL was the percentage of attempts resulting in erections firm enough for intercourse - one of the most rigorous endpoints used in ED trials to date. These data were collected from both patients and their partners by reviewing entries in patient diaries and partner BSFI questionnaires. Secondary endpoints included percentage of attempts resulting in intercourse and improvement in ED severity based on the International Index of Erectile Function (IIEF). The proportion of attempts resulting in erections firm enough for intercourse was 49.4% with 3 mg compared with the baseline value of 24.3%. Partner evaluations corresponded with those of the patients. Erections occurred between 18 and 19 min after taking apomorphine SL 2 or 3 mg. The most common side effect was nausea which declined with continued use. Vasovagal syncope was reported in <0.2% of men, and was preceded by clear prodromal symptoms. Thus, apomorphine SL is an effective, well-tolerated drug for erectile dysfunction.