To Compare the Efficacy and Safety of Tripterygium (TW) Versus AZA in the Maintenance Therapy for Lupus Nephritis

Inclusion Criteria:

1. Patients who signed written informed consent form;
2. SLE patient, aged between 18-60 years, female or male;
3. Patients diagnosed lupus nephritis according to ISN/RPS 2003 classification criteria, class Ⅲ, Ⅳ,Ⅳ+Ⅴ, Ⅲ+Ⅴ or Ⅴ LN by renal biopsy;
4. All patients received induction therapy for 6-12 months, including MMF, CTX, FK506 or multi-target therapy;

5. When recruited in the study, patients received partial remission or complete remission for 3 months;

   • Complete remission: proteinuria < 0.4 g/24h, negative urine sediment, serum albumin > 35 g/L, elevated scr < 0.3 mg/dl, no extra-renal complications;
   • Partial remission: proteinuria < 1.0 g/24h, urine RBC < 500000/ml without casts, serum albumin > 35 g/L, elevated scr <0.3 mg/dl, no extra-renal complications.

Exclusion Criteria:

1. Patients who didn't sign written informed consent form or could not obey the protocol;
2. Patients who didn't received the CR or PR criterion;
3. Patients who have impaired liver function, with ALT/GPT or AST/GOT twice more than the normal upper limit;
4. WBC < 3000/mm3 in peripheral blood;
5. Patients with abnormal of central nervous system.