Teva challenges two of Gilead's Truvada patents

California, USA-based Gilead Sciences says it has received a Paragraph IV Certification Notice Letter advising that Israel-headquartered Teva Pharmaceuticals Industries has submitted an Abbreviated New Drug Application to the Food and Drug Administration requesting permission to manufacture and market a generic version of Truvada (emtricitabine and tenofovir disoproxil fumarate).

In the communication, Teva alleges that two of the patents associated with emtricitabine - US patent numbers 6,642,245 and 6,703,396 - owned by Emory University and licensed exclusively to Gilead, are invalid, unenforceable and/or will not be infringed by Teva's manufacture, use or sale of the product described in its ANDA submission.

Gilead says it is currently reviewing the Notice Letter and has 45 days from its receipt to commence a patent infringement lawsuit against the Israeli generics drug giant. Such a law suit would restrict the FDA from approving Teva's ANDA for up to 30 months or until a district court decision that is adverse to Gilead, whichever occurs first. Truvada is currently protected by 10 patents, which are listed in the FDA's Approved Drugs Products List, and all of those would need to be invalidated or expired before a generic version of Truvada could be marketed, says the US drugmaker.