Sanofi to buy 12 percent of Alnylam, expands rare-disease drug deal

By Ransdell Pierson SAN FRANCISCO (Reuters) – French drugmaker Sanofi will buy a 12 percent stake in Alnylam Pharmaceuticals Inc for $700 million and deepen their partnership to develop drugs for rare genetic diseases. The companies said in a joint statement on Monday that Sanofi would buy Alnylam shares for about $80 each, representing a 27 percent premium compared to their average price over the past 30 days. The partnership between Sanofi and Alnylam began in 2012, the year after Sanofi jumped into the business of treating rare genetic diseases by paying more than $20 billion for U.S. biotechnology company Genzyme, a leader in the field. The Genzyme drugs include blockbuster treatments such as Fabrazyme for a rare condition called Fabry disease and Cerezyme for Gaucher disease.