FDA concerned about generic ADHD drugs

FDA has warned about 2 approved generic versions of Concerta tablets to treat attention-deficit hyperactivity disorder (ADHD).

“FDA has concerns about whether or not 2 approved generic versions of Concerta tablets (methylphenidate hydrochloride extended-release tablets)…are therapeutically equivalent to the brand-name drug,” the agency said in a press statement. The two approved generic versions of Concerta are manufactured by Mallinckrodt Pharmaceuticals and Kudco Ireland Ltd. 

After FDA conducted an analysis of adverse event reports and previous data submitted to the agency, along with its own tests of products manufactured by Mallinckrodt and Kudco, the agency found that the generic products “may not produce the same therapeutic benefits for some patients as the brand-name product, Concerta, manufactured by Janssen Pharmaceuticals, Inc.”, the statement said.

However, FDA found that Actavis, Janssen’s generic equivalent for Concerta, is bioequivalent to, and substitutable for, Concerta. 

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, resulting in patients not having the desired effect, according to FDA.     

As a result, 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,” the FDA stated.

In addition, the agency revised its draft guidance for industry for bioequivalence testing for methylphenidate hydrochloride extended-release tablets (Concerta).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

At the same time, FDA said patients should not make changes to their treatment, except in consultation with their health care professional, since it has not identified any serious safety concerns with the 2 generic products.