Shire has received a Paragraph IV notice letter from Teva Pharmaceuticals USA advising of the filing of an abbreviated new drug application (ANDA) for its mixed amphetamine product.
Adderall XR is the lead product in Shire’s portfolio of treatments for ADHD and is protected by two US patents that expire in 2018.
Shire has already received notice letters from Barr Laboratories, Impax Laboratories and Colony Pharmaceuticals relating to their ANDAs for their respective generic versions of Adderall XR.
Shire has filed lawsuits in response to the Barr and Impax ANDA notice letters and is currently reviewing the detail of the Paragraph IV notice letter from Teva.
The Teva filing also follows the recent blow to Shire that occurred after Adderall XR sales were suspended in Canada following a regulatory safety review. This news caused the company’s shares to drop over 8% and came as a surprise as US regulators, who, when presented with the same safety data, responded by merely revising the product’s warning label.