一病人有狼瘡病腎炎(lupus nephritis),有蛋白尿2.0 gm/day,合併腎功能不足(creatinine 2.0 mg/dL),下列何種藥物,最不適用於此病人?
cyclosporine
leflunomide
rituximab
mycofenolate mofetil