(115) Real-World Evaluation of Onset of Action and Efficacy of a Novel Sildenafil Oral Suspension in Men with Erectile Dysfunction

Abstract Introduction A rapid onset of action of phosphodiesterase type 5 inhibitors (PDE5is) has been recognized as clinically relevant for men with erectile dysfunction (ED). A new oral suspension formulation (OSF) of sildenafil has been introduced. Real-life effectiveness and timing of onset of action (TOA) of this new sildenafil OSF has not yet been investigated. Objective We aimed to assess TOA and efficacy of sildenafil OSF in men with ED. Methods Data from 123 consecutive men seeking first medical help for ED evaluated at four Italian sexual medicine academic clinics were analyzed. Health-significant comorbidities were scored with Charlson Comorbidity Index (CCI). Patients were treated with sildenafil 50 mg OSF on demand for 12 weeks. Patients completed a baseline and follow-up International Index of Erectile Function-erectile function (IIEF-EF) domain and a 8-item self-administered questionnaire about TOA and overall treatment outcomes. Treatment response was evaluated using the minimal clinically important difference (MCID) (from baseline IIEF-EF score: mild: +2; moderate: +5; severe: +7) and the Yang’s criteria stratification for responders, partial responders, and non-responders. Treatment compliance and treatment-emergent adverse events were assessed. Descriptive statistics tested efficacy rates, patient timing of drug intake and post-dosing TOA. Logistic regression models investigated factors associated with treatment efficacy. Results Overall, median (IQR) patient’s age and baseline IIEF-EF scores were 58 (50-65) years and 15 (10-18). A stable sexual relationship was reported by 93 (75.6%) and 79 (64.2%) men were naïve for any previous PDE5i. A baseline mild, moderate and severe ED was found in 41 (33.3%), 49 (39.8%) and 33 (26.9%) patients. Sildenafil OSF significantly improved IIEF-EF at follow-up (15 vs. 22, p0.001). Satisfaction of MCID criteria was observed in 85 (69.1%) cases and complete response was achieved in 21 (17.1%) patients according to Yang’s criteria for treatment effectiveness. 85 (69%) patients self-reported drug dosing within 1 h of any type of sexual attempt. 33 (26.8%) patients reported a rigid erection sufficient for satisfactory vaginal penetration in up to 30 min post-dosing, with 65 (52.8%) patients reporting a post-dosing TOA within 45 min. Patients with a TOA ≤30 min were younger (48 (41-57) vs. 60 (53-67) years, p0.01) and had lower CCI score (0.3 (0.1) vs 0.8 (0-1), p0.01) than those with TOA 30 min. Multivariable logistic regression analysis showed that higher baseline IIEF-EF scores (OR 1.2, p 0.001) were associated with complete response to sildenafil OSF, after accounting for age and CCI. Younger age (OR 0.9, p0.01) was independently associated with TOA ≤30 min, after accounting for CCI. ROC curves showed that age ≤ 51 was the best predictor of TOA ≤30 min (sensitivity 82.2%, specificity 61%, AUC 0.76). Conclusions One in four men treated with sildenafil OSF for ED achieved satisfactory erection within 30 minutes of dosing. Younger age and lower comorbidity burden were independently associated with faster onset of action. Treatment efficacy was observed in approximately 70% of men. Disclosure No