In new phase II results presented recently an investigation intoi beta3-adrenoceptor agonist Solabegron yielded statistically significant improvements in symptoms of overactive bladder (urge incontinence) compared to placebo and was safe and well tolerated, Dutch researchers reported.

The multicenter randomized, double-blind, placebo-controlled parallel-group study compared solabegron in 50 mg and 125 mg, to a placebo in 258 women with moderate to severe overactive bladder (urge incontinence) symptoms (averaging 4.5 incontinence episodes per day), more than half of whom had unsuccessful prior treatment with muscarinic agents. Solabegron, 125 mg, dosed twice daily over 8 weeks, produced a 66.5% reduction from baseline in incontinence episodes, a statistically significant adjusted mean difference from placebo of 25% (p=.025).

Patients treated with the agent also reported a significant reduction in the frequency of urination (−0.8, p=.036) and a marked and significant increase in the volume of urine voided (+27%, p<.001) compared to placebo.

Adverse events did not differ between the placebo and active treatment groups. Unfortunately Headache and nasopharyngitis were the most frequently reported adverse events across treatment groups, with no notable changes in any cardiovascular parameters measured by 24-hour ambulatory blood pressure, clinical chemistry, hematology, or ECG parameters. Urinary retention was not observed.

"Solabegron is efficacious, safe, and well tolerated in the treatment of patients with Overactive Bladder," reported the study authors, led by Martin C. Michel, MD, PhD, of Academic Medical Centre of the University of Amsterdam, Amsterdam, the Netherlands. A phase IIb/III study of solabegron for OAB is planned to start enrolling later this year.