FEDERAL COURT INVALIDATES SANOFI-AVENTIS' LOVENOX PATENT

Sanofi-aventis' antithrombotic Lovenox could soon be open to generic competition as a result of a federal court ruling that invalidated the firm's patent on the drug.

The U.S. District Court for the Central District of California last week granted Amphastar Pharmaceuticals and Teva Pharmaceutical a motion for summary judgment that invalidated sanofi-aventis' '618 patent for Lovenox (enoxaparin sodium) based on inequitable conduct concerns. The patent covers Lovenox's active ingredient and was not set to expire until Feb. 14, 2012. Lovenox was sanofi-aventis' top-selling drug in 2004, generating global sales of $2.6 billion.

The district court ruling stems from a lawsuit filed by sanofi-aventis in August 2003 that accused Amphastar and Teva of violating the '618 patent by filing abbreviated new drug applications (ANDA) for enoxaparin. That lawsuit triggered a 30-month stay prohibiting the FDA from approving any abbreviated new drug application (ANDA) for generic Lovenox until the case was decided.

If the court enters the ruling as a final judgment, the 30-month stay would be lifted, potentially allowing generic versions of the drug to enter the market. While Amphastar and Teva have both submitted ANDAs for enoxaparin to the FDA, the agency hasn't granted final approval to either firm.

In addition to Teva and Amphastar, early-stage biotechnology company, Momenta Pharmaceuticals, plans to file an ANDA in mid-2005 for generic Lovenox in partnership with generic drugmaker Sandoz, according to Andrew McDonald, a biotechnology analyst with ThinkEquity Partners.

Sanofi-aventis said it intends to appeal the district court's decision to the U.S. Court of Appeals for the Federal Circuit if the ruling is entered as a final judgment.