Safety and potential efficacy of tacrolimus for treatment of lupus nephritis with persistent proteinuria

Objectives To evaluate the safety and potential efficacy of tacrolimus for the treatment of patients with lupus nephritis and persistent proteinuria. Methods A total of 23 Japanese patients with lupus nephritis (21 females / 2 males) were enrolled in this study. Patients were administered tacrolimus at a dose of 2-3 mg once daily after the evening meal for 6 months. The dose of tacrolimus was unchanged throughout the study period. Concomitant prednisolone therapy was unchanged or gradually tapered, while other immunosuppressants were stopped at the start of tacrolimus treatment. Results Tacrolimus was well tolerated, and none of the patients developed adverse drug reactions that required discontinuation of the study. Daily urinary protein loss, the U-prot/U-creat ratio, and serum albumin were significantly improved after 4 months, 3 months, and 1 month of treatment with tacrolimus (p<0.05), respectively, and the improvement persisted until 6 months. The serum complement hemolytic activity (CH50), complement C3 level, and CRP level were also significantly improved after treatment with tacrolimus (p<0.05). Improvement of the U-prot/U-crcat ratio was most prominent for patients who were in WHO class IV Conclusion Tacrolimus is safe and effective as maintenance therapy for patients with lupus nephritis, at least for 6 months. A larger randomised, controlled trial over a longer period is needed to confirm these results.