Sanofi Takes Patent Hit

Plavix is a pill that prevents blood platelets from sticking together, reducing the risk of a heart attack or stroke. Platelets are essential for stopping excessive bleeding after an injury, but they also can lead to clots in arteries if they pile up next to accumulations of plaque caused by cholesterol.

A legal defeat for Lovenox would be worse than a courtroom loss for Plavix because Sanofi markets Lovenox by itself in the U.S. Bristol-Myers Squibb(BMY Quote) sells Plavix in the U.S.

Sanofi, Teva and Amphastar have been fighting in court since August 2003. In June 2005, a federal judge granted the challengers summary judgment in a dispute over two Lovenox patents. In April 2006, a federal appeals court reversed the decision and sent the case back to the trial court. The major issue was whether Sanofi tried to mislead to the U.S. Patent and Trademark Office. The District Court retried the case in December.

Some analysts say Sanofi may avoid an immediate generic attack because Lovenox's complex formula makes it difficult for other companies to copy.

The legal defeat "is not wholly unexpected" even though Sanofi could appeal," said David Beadle of UBS Securities in a note to investors.

Because generic-drug makers must prove their products are bioequivalent to brand-name drugs, Beadle says it is "unlikely" that Teva and Amphastar can secure FDA approval. Bioequivalent means a generic must have the same strength and reach the desired target in the same way as a brand-name drug.