This is a multicenter, randomised, double-blind placebo controlled trial on the efficacy and
safety of add-on metformin to conventional immunosuppressants in systemic lupus erythematosus
(SLE).
The purpose of this study is to evaluate: 1) the effect of metformin on reducing disease
flares; 2) the influence of metformin on corticosteroid sparing effect; 3) the influence of
metformin on body mass index (BMI); 4) the safety of metformin.