The U.S. Food and Drug Administration (FDA) has approved Anturol (oxybutynin) topical gel 3% for the treatment of overactive bladder (OAB) with symptoms of urge urinary incontinence, urgency, and frequency.

Anturol is a topical, translucent hydroalcoholic gel containing oxybutynin, an antispasmodic, antimuscarinic agent. Applied once daily to the thigh, abdomen, upper arm or shoulder, an 84 mg (approx. 3 mL) dose delivers a consistent dose of oxybutynin through the skin over a 24-hour period, providing significant efficacy without sacrificing tolerability.

The approval of Aturol is based on a 12-week, multi-center placebo controlled Phase 3 clinical study conducted by Antares. Patients were randomized to either an 84 mg or 56 mg dose application of oxybutynin gel 3% versus placebo. The FDA approved the 84 mg dose application. Patients treated with 84 mg oxybutynin gel daily achieved steady state drug concentrations within three days and experienced a statistically significant decrease in OAB symptoms versus placebo, including the number of urinary incontinence episodes per week. Statistically significant improvements in daily urinary frequency and urinary void volume were also seen with the 84 mg dose.

The product was well tolerated in the study. The most frequently reported treatment-related adverse events (>3%) were dry mouth (12.1% versus 5% in placebo), application site erythema (3.7% versus 1.0% in placebo) and application site rash (3.3% versus 0.5% in placebo). Because the active ingredient is delivered transdermally, it is not metabolized by the liver in the same way as orally administered oxybutynin. This results in a low level of side effects, such as dry mouth and constipation.

Additional pharmacokinetic studies showed that showering one hour or later, or the application of sunscreen 30 minutes before or after gel application had no affect on the overall systemic exposure of the drug.

Patient Information for Anturol

Important: For use on the skin only (topical). Do not get Anturol in or near your eyes, nose, or mouth. Read this Patient Information carefully before you start taking Anturol and each time you get a refill. There may be new information. This information does not take the place of talking with your doctor about your medical condition or your treatment.

What is Anturol?

Anturol is a prescription medicine used to treat the symptoms of overactive bladder including:

• a strong need to urinate with leaking or wetting accidents (urge urinary incontinence)
• a strong need to urinate right away (urgency)
• urinating often (frequency)

It is not known if Anturol is safe or effective in children.

source:FDA