Genentech Inc. and U.S. regulators have added a new warning for the biotech firm’s psoriasis drug Raptiva about the risk of serious infections, according to a letter made public on Wednesday. The drug also carries a risk of a decreased blood platelets and a type of anemia called immune-mediated hemolytic anemia, said the letter to doctors dated July 15.Swiss drugmaker Roche Holding AG has a majority stake in Genentech.
