TEVA SUED OVER CHALLENGE TO ADDERALL XR

Shire has sued Teva Pharmaceutical over its generic challenge to Shire's attention-deficit/hyperactivity disorder drug Adderall XR.

The lawsuit, filed recently in the U.S. District Court for the Eastern District of Pennsylvania, alleges Teva's abbreviated new drug application for a version of Adderall XR infringes on two patents covering the drug.

Teva aims to market multiple strengths of Adderall XR (amphetamine aspartate/amphetamine sulfate/dextroamphetamine saccharate/dextroamphetamine sulfate extended-release). Shire's lawsuit triggers a 30-month stay on FDA approval of Teva's proposed 25-mg product, the firm said.

The Teva lawsuit follows Shire's agreement in January to settle patent litigation with Impax Laboratories over its challenge to the drug. Under the deal, Impax is allowed to market generic versions of Adderall XR no later than Jan. 1, 2010. In exchange, Impax will pay royalties to Shire. In addition, Impax could launch an authorized generic earlier than 2010 if another generic version of Adderall XR hits the market. Shire has been in settlement talks with Barr Pharmaceuticals over its challenge to the drug.