Efficacy of TAC-302 for patients with detrusor underactivity and overactive bladder: a randomized, double-blind, placebo-controlled phase 2 study

Purpose This multicenter, randomized, double-blind, placebo-controlled phase 2 study evaluated the efficacy and safety of TAC-302, a novel drug that restores neurite outgrowth, in patients with detrusor underactivity (DU) and overactive bladder (OAB). Methods After 2–4 weeks of observation, patients were randomized 2:1 to receive oral TAC-302 200 mg or placebo twice daily for 12 weeks. The primary endpoint was detrusor contraction strength, estimated by bladder contractility index (BCI) for males and projected isovolumetric pressure 1 (PIP1) for females. Secondary endpoints included changes in bladder voiding efficiency (BVE) and safety. Results Seventy-six patients were included (TAC-302, n = 52; placebo, n = 24). The mean (standard deviation [SD]) BCI for males was 64.6 (16.6) at baseline and 75.2 (21.1) at week 12 ( p < 0.001) with TAC-302 ( n = 27), and 61.3 (16.6) and 60.5 (16.7) ( p = 0.82) with placebo ( n = 11). The respective mean (SD) PIP1 for females was 18.8 (6.6) and 29.4 (9.4) ( p < 0.001) with TAC-302 ( n = 15), and 20.6 (7.5) and 25.5 (9.6) ( p = 0.14) with placebo ( n = 7). TAC-302 significantly increased BCI in males and BVE in both sexes. TAC-302 efficacy on OAB was not clearly shown. The incidences of adverse events (AEs), serious AEs, and AEs leading to dose interruption were similar between groups; no adverse drug reactions occurred. Conclusion Considering the significant effects on BCI in males and BVE in both sexes, TAC-302 may benefit patients with DU. Registration ClinicalTrials.gov Identifier NCT03175029 registered 6/5/2017.