Sanofi Takes Patent Hit

"The FDA's correspondence with Amphastar indicates a lack of conviction on the part of the agency that its product is equivalent to Lovenox," said Michael King, of Rodman & Renshaw, in a research report. "Publicly available documents argue that [Teva's] product also faces substantial hurdles in its effort to demonstrate equivalency."

King and Beadle say there's a better chance that the FDA could approve a generic from Momenta Pharmaceuticals(MNTA Quote), which is working with the Sandoz unit of Novartis(NVS Quote). Sandoz is the No. 2 generic-drug maker.

Beadle says the FDA might approve a generic by midyear. Beadle's firm has had a recent investment banking relationship with Sanofi-Aventis.