Effectiveness of Mycophenolate Mofetil Combined With Tacrolimus for Steroid Tapering in Systemic Lupus Erythematosus

According to the references, with the maintenance of steroid, 1-year lupus flare rate is 7%. Investigators plan to take a 2-year follow-up for participants, so the proportion of patients without flare in steroid maintenance group should be 86%. As this is a non-inferiority study, investigators hypothesize that in steroid tapering group, the proportion of patients without flare is also 86%. Investigators set α=0.05 (two-sided), 1-β=0.90, non-inferiority value = 15%, the dropout rate = 20%. The sample size of each group should be 110, the 220 in total.