Generic drugmaker Actavis has filed a legal challenge against Takeda subsidiary Millennium Pharmaceuticals seeking to overturn its US patent protection on multiple myeloma and mantle cell lymphoma treatment Velcade.
Actavis' new parent company Watson Pharmaceuticals said the company had filed for approval of a generic product based on bortezomib, the active ingredient in Velcade, and had promptly been sued by Millennium for patent infringement.
Under US law, the lawsuit introduces an immediate 30-month stay on FDA approval of the generic unless Actavis can overturn patents protecting Velcade.
Millennium's defence of Velcade rests on two US patents (6,713,446 and 6,958,319) which were filed in 2005 and are both due to expire on January 5, 2022, according to court documents filed by the company.
Velcade is Millennium's biggest-selling product and had sales of around $740m in the 12 months ending October 31, 2012, according to IMS Health data.
The drug acts as a proteasome inhibitor and was first approved in the US in 2003 as an intravenous therapy and is now also available in a subcutaneous formulation.
Outside the US it is marketed by Johnson & Johnson, which said in November it recorded almost $1bn in sales for the product in the first nine months of 2012, a 16 per cent increase driven by approvals of the subcutaneous formulation in the EU and Canada.