Shares of Acambis soared after Sanofi Pasteur, the vaccine division of Sanofi-Aventis, announced that it planned to buy the vaccine developer for $548 million. Aside from the smallpox vaccine ACAM2000, which recently won a 10-year, $425 million contract from the U.S. government, Sanofi-Aventis also gains a slate of experimental vaccines for dengue fever, West Nile disease and clostridium difficile, influenza and genital herpes.
Sanofi Pasteur and Acambis are partnered on a variety of development programs already. And the deal underscores just how attractive vaccine companies have become. Sanofi-Aventis "quite liked what we had in Acambis," said Acambis Chief Executive Ian Garland.