businessweek.com — A late-stage study of Pfizer Inc.'s experimental drug for moderate-to-severe rheumatoid arthritis found it worked better than the standard treatment, Pfizer said Tuesday. Pfizer released limited results of the study, called ORAL Start, of its tofacitinib. It's a new type of drug to fight the painful chronic inflammatory disorder, in which the immune system attacks the body's joints, particularly the hands and feet.