Andrx Corporation has entered into an agreement to obtain certain exclusive marketing rights for both strengths of Amphastar Pharmaceuticals, Inc.'s proposed generic version of Lovenox, Aventis Pharmaceuticals, Inc.'s enoxaparin sodium injectable product.

Amphastar submitted its Abbreviated New Drug Application for generic Lovenox to the FDA in March 2003. Amphastar's product is the subject of a patent infringement lawsuit filed by Aventis, and the 30-month stay imposed by law, which runs through February 2006. Lovenox is indicated for the prevention of deep vein thrombosis in certain patients undergoing abdominal surgery and knee or hip replacement surgery, and for the prevention of certain cardiovascular events. According to IMS Health data, Lovenox generated total 2004 US sales of approximately $1.5 billion.

Andrx's marketing rights generally extend to the US retail pharmacy market, representing approximately 30 per cent of total Lovenox sales. To obtain such rights, Andrx paid $4.5 million upon execution of the agreement and will make an additional $5.5 million payment to Amphastar once certain milestones relating to the product are achieved, including obtaining FDA marketing approval and a favourable resolution of the pending patent litigation. In exchange, Andrx will receive up to 50 per cent of the net profits, as defined, generated from sales of Amphastar's product in the retail pharmacy market. Under certain specified conditions, Andrx has the right to receive a refund of the amounts it paid to Amphastar, stated a company release.