Concerns about two approved, generic versions of Concerta for attention-deficit/hyperactivity disorder in children and adults have led to new therapeutic ratings for each, the Food and Drug Administration has announced.
The two methylphenidate hydrochloride extended-release tablets, manufactured respectively by Mallinckrodt Pharmaceuticals and Kudco Ireland, were changed from therapeutic equivalence ratings of AB to BX after the FDA conducted a review of adverse event reports, previously submitted data, and FDA laboratory tests of products manufactured at the two sites. The FDA also analyzed an authorized Concerta (Janssen) generic, manufactured by Janssen and marketed by Actavis, but found no evidence to change its therapeutic rating.
The revised therapeutic equivalence rating for the two generics does not change their approved status, but it does mean they are no longer recommended as an automatic pharmacy substitution for Concerta.
The FDA has not identified any serious safety issues with the two generics, and has urged patients using either medication to change their treatment unless instructed to do so by their health care provider.
The methylphenidate hydrochloride extended-release generics are supposed to release the drug in the body over a 10- to 12-hour period, making it equivalent in effect to a three times per day dose of the immediate-release version. However, the FDA said in a statement that the Mallinckrodt and Kudco generics might deliver the drug in the body at a slower rate between hours 7 and 12, leaving patients with less therapeutic effect.
Mallinckrodt and Kudco have 6 months either to confirm the bioequivalence of their products using the FDA’s revised draft guidance for industry for testing methylphenidate hydrochloride extended-release tablets or to voluntarily withdraw their respective products from the market.
Meanwhile, the FDA has stated that its evaluation of testing and approval standards, and bioequivalence guidances for other generic methylphenidate hydrochloride extended-release products, is ongoing.
Health care professionals and consumers should report adverse events associated with these products by visiting the FDA’s MedWatch site, www.fda.gov/Safety/MedWatch/HowToReport/default.htm , or by calling 800-332-1088.