A multicenter, double-blind, randomized, placebo-controlled trial of the ß3-adrenoceptor agonist solabegron for overactive bladder.

BACKGROUND: ß-Adrenoceptor agonists are effective in animal models of bladder dysfunction, and the human bladder primarily expresses the ß3 receptor subtype. OBJECTIVE: To evaluate the efficacy and tolerability of the highly selective and potent ß3-adrenoceptor agonist solabegron in a clinical proof-of-concept study in incontinent women with overactive bladder (OAB). DESIGN, SETTING, AND PARTICIPANTS: This was a randomized, double-blind trial in adult women with OAB (one or more 24-h incontinence episodes and eight or more average 24-h micturitions). INTERVENTIONS: Solabegron 50 mg (n=88), solabegron 125 mg (n=85), or placebo (n=85)-all twice daily-were administered. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary efficacy end point was percentage change from baseline to week 8 in the number of incontinence episodes over 24 h. Secondary end points included actual change and percentage change from baseline to week 4 and week 8 in micturitions per 24 h, urgency episodes per 24 h, and volume voided per micturition. Adverse events (AEs) were assessed, as well. RESULTS AND LIMITATIONS: Solabegron 125 mg produced a statistically significant difference in percent change from baseline to week 8 in incontinence episodes over 24h when compared with placebo (p=0.025). Solabegron 125 mg treatment also showed statistically significant reductions from baseline to weeks 4 and 8 in micturitions over 24 h and a statistically significant increase from baseline to week 8 in urine volume voided. Solabegron was well tolerated, with a similar incidence of AEs in each treatment group. There were no significant treatment differences for mean changes from baseline to week 8 in systolic blood pressure (BP), diastolic BP, mean arterial pressure (MAP), or heart rate during the 24-h ambulatory measurement. CONCLUSIONS: Solabegron significantly reduced the symptoms of OAB in women with moderate to severe OAB. Solabegron was safe, well tolerated, and did not demonstrate significant differences in AEs as compared to placebo. ß3-Adrenoceptor agonists may represent a new therapeutic approach for treating OAB symptoms.

A multicenter, randomized, double-blind, crossover study to evaluate patient preference between tadalafil and sildenafil.

PURPOSE: To assess patient preference for erectile dysfunction treatment between either sildenafil or tadalafil, each administered with their respective dosing instructions, and to evaluate preference for either sildenafil or tadalafil dosing instructions during tadalafil therapy. METHODS: We conducted a randomized, double-blind, crossover study consisting of four treatment arms. Because the dosing instructions for sildenafil and tadalafil are different, a unique methodology using sham placebo arms was employed to maintain the blind. To assess drug preference, 219 patients were randomized to either sildenafil 50 mg or tadalafil 20 mg, with dosing instructions reflecting their respective product profiles. To assess dosing instruction preference during tadalafil therapy, 46 patients were randomized to tadalafil 20 mg with either tadalafil or sildenafil dosing instructions. After 12 weeks, patients were crossed-over. After 4 weeks of each treatment, all patients following sildenafil dosing instructions were offered the opportunity for an upward dose titration. In a double-blind fashion, all patients who requested an upward titration received additional capsules. To mimic the pattern of dose usage observed in clinical practice, the number of patients who received additional double-blind active medication was limited to 35% of patients taking sildenafil in each treatment period in each country. Following the crossover treatment period, patients chose their preferred double-blind treatment with dosing instructions to receive in the 12-week extension period. RESULTS: In the drug preference assessment, 132 of 181 (73%) evaluable patients chose to receive tadalafil (p < 0.001) during the extension period. In the dosing instruction preference assessment, 24 of 36 (67%) evaluable patients preferred tadalafil with tadalafil dosing instructions (p = 0.046). Sildenafil and tadalafil were well tolerated. CONCLUSIONS: In the doses utilized in this study, 73% of patients preferred tadalafil with tadalafil dosing instructions for the treatment of their erectile dysfunction over sildenafil with sildenafil dosing instructions. During tadalafil therapy, 67% of patients preferred tadalafil dosing instructions over sildenafil dosing instructions.