Efficacy and Safety of Gabapentin in Comparison to Solifenacin Succinate in Adult Overactive Bladder Treatment

OBJECTIVE: To evaluate the efficacy and safety of gabapentin in comparison to solifenacin succinate and placebo for the treatment of adult patients with overactive bladder (OAB). METHOD: A 12-week, randomized, double-blind, double dummy placebo-controlled, clinical trial was conducted between October 2010 and August 2014 at a tertiary medical center. Eligible and consenting patients included were randomized into three treatment groups (placebo, gabapentin and solifenacin). After a 12-week treatment period, an intention to treat analysis was applied to assess between group differences on the micturitions and urgency episodes per 24 h; which were evaluated by 3-day micturition diary mean change from baseline to post treatment. Health related quality of life (HRQOL) domains were likewise assessed by OAB questionnaire (OAB-q). Adverse event were monitored and summarized. Study results were analyzed at statistical significance of 0.05. (ClinicalTrials.gov ID NCT01486706) RESULT: A total of 94 participants were included for end-study efficacy and safety analysis. Compared to placebo, gabapentin and solifenacin have statistically significant improvement in mean number of micturitions per 24 h (adjusted mean difference [AMD] -1.179, 95%CI -1.98, -0.38; P < 0.001; -1.706, 95%CI -2.52, -0.09; P < 0.001; respectively), and in mean number of urgency episodes per 24 h (AMD -0.903, 95%CI -1.44, -0.37; P < 0.001; -0.896, 95%CI -1.44, -0.35; P < 0.001). Gabapentin also demonstrated significant improvement over the solifenacin in the mean number of nocturia episodes/24 h (AMD -0.607, 95%CI -1.04, -0.18; P < 0.001). Adverse event related to gabapentin treatment was lesser than solifenacin, and comparable to placebo. CONCLUSION: Gabapentin treatment with acceptable safety profile, improves OAB symptoms and HRQOL domains.