Efficacy and safety of multitarget therapy with cyclophosphamide and tacrolimus for lupus nephritis: a prospective, single-arm, single-centre, open label pilot study in Japan

Background Pulsed cyclophosphamide or mycophenolate mofetil for lupus nephritis has limited efficacy. We previously reported a case of mixed-class IV+V lupus nephritis successfully treated with cyclophosphamide and tacrolimus. This study assessed the efficacy and safety of multitarget therapy with cyclophosphamide and tacrolimus for the treatment of lupus nephritis. Methods In a prospective, single-arm, open label pilot study, we recruited 15 patients aged 18-64 years with active lupus nephritis who met the American College of Rheumatology criteria for a diagnosis of systemic lupus erythematosus (1997). The treatment protocol was a starting dose of prednisolone of 0.6-1.0mg/kg/day for 2 weeks and then tapered to a maintenance dose, intravenous cyclophosphamide (500mg biweekly for 3 months) and tacrolimus (3.0mg/day). Tacrolimus was continued as maintenance therapy. Complete remission was defined as a spot urine protein/creatinine ratio of<0.5g/gCr with no active urine casts and a serum creatinine level that was either normal or within 30% of a previously abnormal baseline level. We retrospectively compared results for the study patients with those of 18 historical controls conventionally treated with cyclophosphamide and prednisolone. Results At baseline, the mean patient age was 41.514.6 years (male:female ratio 2:13), urine protein/creatinine ratio 3.92.3g/gCr and serum creatinine 84.6 +/- 34.6 mu mol/L. Lupus nephritis classifications included classes IV (n=8), III+V (n=1), IV+V (n=5) and unclassified (n=1). Eleven patients completed the treatment protocol and four withdrew. At 6 months, 12 of 15 (80.0%) had achieved complete remission using intention-to-treat analysis, significantly more than historical controls (seven of 18 patients, 38.9%). A transient increase in serum creatinine and gastric symptoms occurred in three cases. One patient withdrew due to cytomegalovirus antigenemia and severe diabetes, and one patient died of thrombotic microangiopathy. Conclusions Multitarget therapy with cyclophosphamide and tacrolimus can be a therapeutic option for lupus nephritis. Clinical trials registration Combination therapy of tacrolimus and intravenous cyclophosphamide for remission induction of lupus nephritis, UMIN: 000004893, URL: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000005830&language=E. Date of registration: 18 January 2011.