FDA Concerns About Therapeutic Equivalence with Two Generic Versions of Concerta Tablets

Based on an analysis of data, FDA has concerns about whether or not two approved generic versions of Concerta tablets (methylphenidate hydrochloride extended-release tablets), used to treat attention-deficit hyperactivity disorder in adults and children, are therapeutically equivalent to the brand-name drug. The two approved generic versions of Concerta are manufactured by Mallinckrodt Pharmaceuticals and Kudco Ireland Ltd.

FDA has not identified any serious safety concerns with these two generic products. 

FDA’s Scientific Evaluation of Generic Concerta Products

An analysis of adverse event reports, an internal FDA re-examination of previously submitted data, and FDA laboratory tests of products manufactured by Mallinckrodt and Kudco have raised concerns that the products may not produce the same therapeutic benefits for some patients as the brand-name product, Concerta, manufactured by Janssen Pharmaceuticals, Inc. Janssen also manufactures an authorised Concerta generic, which is marketed by Actavis under a licensing agreement and is identical to Janssen’s Concerta. FDA included the authorised generic in its analysis and found it to be bioequivalent to, and substitutable for, Concerta. Apart from the Mallinckrodt, Kudco, and Actavis products, there are no other generics for Concerta.

Methylphenidate hydrochloride extended-release products approved as generics for Concerta are intended to release the drug in the body over a period of 10 to 12 hours. This should allow for a single-dose product that is consistent with the effect of a three times per day dose of immediate-release methylphenidate hydrochloride.

In some individuals, the Mallinckrodt and Kudco products may deliver drug in the body at a slower rate during the 7- to 12-hour range. The diminished release rate may result in patients not having the desired effect.

As a result, the FDA has changed the therapeutic equivalence (TE) rating for the Mallinckrodt and Kudco products from AB to BX. This means the Mallinckrodt and Kudco products are still approved and can be prescribed, but are no longer recommended as automatically substitutable at the pharmacy (or by a pharmacist) for Concerta.

Consequently, FDA has revised its draft guidance for industry for bioequivalence testing for methylphenidate hydrochloride extended-release tablets (Concerta). FDA has asked that within 6 months, Mallinckrodt and Kudco confirm the bioequivalence of their products using the revised bioequivalence standards, or voluntarily withdraw their products from the market.

FDA will continue to evaluate its testing and approval standards and bioequivalence guidances for other generic methylphenidate hydrochloride extended-release products and revise as needed.