A double blind, randomised study of sildenafil citrate for erectile dysfunction in men with multiple sclerosis. Evaluation of the safety and efficacy of sildenafil citrate for erectile dysfunction in men with multiple sclerosis: a double-blind, placebo controlled, randomized study.
Identifying and effectively treating erectile dysfunction (ED) can result in an improvement of the quality of life (QoL) in men with multiple sclerosis (MS).
                This randomised, double blind (DB), placebo controlled, flexible dose study with an open label extension (OLE) assessed efficacy, QoL, and safety of sildenafil citrate in men with MS and ED. Overall, 217 men received sildenafil (25-100 mg; n = 104) or placebo (n = 113) for 12 weeks. Efficacy was assessed by the International Index of Erectile Function (IIEF) questionnaire that includes questions on achieving (Q3) and maintaining (Q4) an erection as well as a global efficacy question (GEQ). QoL was also assessed.
                After 12 weeks, patients receiving sildenafil had higher mean scores for IIEF Q3 and Q4 compared with those receiving placebo (p<0.0001), and 89% (92/103) reported improved erections compared with 24% (27/112) of patients receiving placebo (p<0.0001). At the end of the OLE phase, 95% of men reported improved erections. Patients receiving placebo during the DB phase showed a nearly fourfold increase in improved erections (97% v 26%). Men receiving sildenafil also showed improvements in five of the eight general QoL questions compared with men receiving placebo (p<0.05). The total mean score for the QoL questionnaire improved by 43% for the sildenafil group versus 13% for the placebo group (p<0.0001). Treatment related AEs were predominantly mild in nature, and no patient discontinued due to an AE.
                Sildenafil treatment for ED in men with MS was effective and well tolerated, and resulted in significant improvements in both general and disease specific QoL variables. We evaluated the safety and efficacy of sildenafil citrate for treating erectile dysfunction in patients with multiple sclerosis.
                A total of 203 patients with multiple sclerosis (age range 18 to 50 years old) with erectile dysfunction were randomly assigned to receive 50 to 100 mg sildenafil (102 patients in group 1) or a similar regimen of placebo (101 patients in group 2) 45 minutes to 2 hours before sexual stimulation. Patients were asked to use at least 24 doses/attempts at home. Primary outcome measures consisted of responses to questions 3 and 4 from the International Index of Erectile Function questionnaires well as responses to Sexual Encounter Profile diary questions 2 and 3. We also assessed the number of attempts at sexual intercourse, the number of attempts that were successful and adverse drug effects.
                Improved erections (positive response to the Global Assessment Questionnaire) were reported by 32.8% of patients receiving sildenafil and 17.6% of those receiving placebo (p = 0.04). For Sexual Encounter Profile question 2 (successful penetration) the increase from baseline in mean per patient percentage of yes responses was 29.4% after sildenafil vs 18.8% after placebo (p = 0.04). The proportion of successful sexual attempts ranged from 12% to 26% for sildenafil and from 9% to 21% for placebo, respectively (p = 0.044). Of patients taking sildenafil and placebo 24 (23.5%) and 9 (8.9%) experienced 81 and 31 adverse events, respectively (p = 0.01).
                Compared with placebo, sildenafil has little effect on multiple sclerosis emergent erectile dysfunction and, therefore, cannot be recommended for the routine treatment of erectile dysfunction in patients with multiple sclerosis. This finding implies that there must be other mechanisms that are not affected by sildenafil or are resistant to the effects of sildenafil.
There is limited evidence to support sildenafil citrate as an effective treatment for ED in patients with MS. Future well designed randomised, double blinded, placebo-controlled trials with long-term duration are needed.