FDA staff raise safety concerns over Sanofi MS drug Lemtrada

Fri Nov 8, 2013 9:16am EST

Nov 8 (Reuters) - U.S. regulatory officials raised concerns about "multiple serious and potentially fatal safety issues" in patients given Sanofi's new multiple sclerosis drug Lemtrada, raising concerns over its approval.

Shares in Sanofi fell 2 percent after the documents were posted on the FDA's website on Friday.