Lilly to stop rheumatoid arthritis drug trial due to lack of efficacy Thu Dec 13, 2012 8:18am EST (Reuters) - Eli Lilly and Co said it will stop one of three late-stage trials of its rheumatoid arthritis drug tabalumab due to insufficient efficacy. The decision was not based on safety concerns, and patients currently enrolled in other tabalumab rheumatoid arthritis studies will continue treatment, Lilly said. The decision to stop the study, called FLEX-M, is expected to result in an after-tax charge of about 2 cents per share in the fourth quarter.