The US Food and Drug Administration (FDA) has asked Kremers Urban Pharmaceuticals Inc. (KU) to submit additional bioequivalence study based on recently issued draft guidance to confirm the therapeutic equivalence of the company's methylphenidate hydrochloride extended-release (ER) tablets (CII) to the category reference drug Concerta.

Until additional data is provided, the agency has changed the therapeutic rating for KU's methylphenidate ER from AB to BX, which means the product is still approved and can be prescribed, but is not recommended as automatically substitutable at the pharmacy for the brand-name drug.

KU intends to perform the requested additional study and will work with the agency in the best interests of patients.

Concerta is a registered trademark of Alza Corporation.

Kremers Urban Pharmaceuticals Inc. (KU) is the generic subsidiary of UCB in the US. It is a specialty generic pharmaceutical company focused on difficult, "high barrier to entry" generic products.