Pfizer and UCB unit Schwarz Pharma are celebrating the news that US regulators have given the go-ahead for their incontinence treatment Toviaz.

The US Food and Drug Administration has approved Toviaz (fesoterodine) extended release tablets for the treatment of overactive bladder symptoms. The drug is a once-daily treatment which can significantly reduce the number of urge urinary incontinence episodes and the frequency of urination over 24 hours, Pfizer noted.

The approval is based on two 12-week Phase III studies of 1,964 OAB patients who showed up to an 88% median reduction in urge urinary incontinence with Toviaz 8mg versus 50% with placebo. Treatment with the drug reduced the number of urinations per day by up to 19% compared to 11% with placebo and reductions in wetting accidents were seen as early as week two of treatment.

Toviaz, an antimuscarinic agent, is structurally related to the most prescribed OAB drug, Pfizer’s own Detrol/Detrusitol XL (extended-release tolterodine). Nancy Muller, executive director of the USA’s National Association for Continence, noted that “the emotional and social implications for people who suffer from OAB are challenging, yet the condition remains underdiagnosed and highly undertreated”.

OAB affects an estimated one in six Americans, “yet still remains highly undertreated”, Pfizer said, adding that the drug is currently available in Europe.