Evaluating the effectiveness and safety of TAC-302 in patients with detrusor underactivity and overactive bladder.

This study evaluated the effectiveness and safety of TAC-302 in patients with detrusor underactivity (DU) and overactive bladder (OAB). The study found that TAC-302 may benefit patients with DU.

Overactive bladder (OAB) occurs when the bladder muscle is too active. Instead of staying at rest as urine fills the bladder, the bladder contracts. This causes a person to feel a sudden and sometimes overwhelming urge to urinate even when the bladder is not full. OAB syndrome is characterized by symptoms such as experiencing incontinence (involuntary leakage of urine), having a strong urge to urinate, and being woken up at night due to the need to urinate (nocturia). OAB symptoms can have a significant negative effect on the quality of life of patients.

Detrusor underactivity, or underactive bladder (UAB), occurs when the bladder muscle is underactive. Patients require a prolonged time to pass urine. DU is characterized by symptoms such as poor or slow urinary stream, needing to push and strain to empty the bladder, and feeling like the bladder has not emptied completely.

TAC-302 is a new drug which restores neurite outgrowth. Neurite outgrowth is a process wherein developing neurons (brain cells) produce new projections as they grow in response to nerve growth factors. However, the effectiveness and safety of TAC-302 in patients with DU and OAB are still unknown.

This study involved 76 patients with DU and OAB. Patients were randomly assigned into two groups. Group 1 included 52 patients who received TAC-302 (200 mg) twice daily for 12 weeks. Group 2 included 24 patients who received a placebo. The detrusor (bladder muscle) contraction strength was estimated by bladder contractility index (BCI) for males and projected isovolumetric pressure 1 (PIP1) for females.

In group 1, the average BCI for males was 64.6 at the start of treatment and significantly improved to 75.2 at week 12. In group 2, the average BCI for males was 61.3 at the start of treatment and 60.5 at week 12.

In group 1, the average PIPI for females was 18.8 at the start of treatment and significantly improved to 29.4 at week 12. In group 2, the average PIPI for females was 20.6 at the start of treatment and 25.5 at week 12.

The average number of urinations, and urgency episodes in 24 hours were not significantly different between groups. 

Serious side effects were similar between the two groups.

This study concluded that TAC-302 may benefit patients with DU.

This study was funded by Taiho Pharmaceutical Co., Ltd, the manufacturer of TAC-302. The sample size was very small. This study only included Japanese patients. The effectiveness of TAC-302  on OAB was not clearly evaluated.