Background: When receiving immunosuppressive therapy, patients with idiopathic nephrotic syndrome who are also carriers of hepatitis B virus (HBV) surface antigen (HBsAg) are at risk for reactivation of HBV.
Objective: This study compared the effectiveness and tolerability of a standard-dose prednisone regimen with those of the combination of mycophenolate mofetil (MMF) and a lower prednisone dose for the treatment of idiopathic nephrotic syndrome characterized by minimal-change nephropathy or slight mesangial proliferative glomerulonephritis in Chinese adults who were also carriers of HBsAg, a combination here termed MSNS-HBV.
Methods: This was a prospective, open-label cohort study in Chinese adults with MSNS-HBV. Patients were self-assigned to 1 of 2 treatment groups: the standard prednisone regimen of 1 mg/kg daily or oral MMF 0.5 to 1.0 g BID combined with the lower prednisone dose of 0.5 mg/kg daily. The planned duration of treatment was 36 weeks, with an additional 60 weeks of follow-up. The primary outcome measures were rates of complete remission of idiopathic nephrotic syndrome (a decrease in daily proteinuria to within the normal range [<0.3 g]) and rates of HBV reactivation (detectable serum HBV DNA). Secondary outcome measures included relapse rates (>1+ albuminuria on dipstick urinalysis on 3 consecutive days), alanine aminotransferase (ALT) elevations (>50 U/L), use of lamivudine 100 mg/d (added if HBV DNA titers reached >or=10(5) copies/mL), and adverse effects.
Results: The intent-to-treat population included 41 patients (22 prednisone, 19 MMF). In patients who completed the study, rates of complete remission after 24 weeks of treatment were 78.9% (15/19) in the prednisone group and 76.5% (13/17) in the MMF group; 2 and 3 patients in the respective groups had a partial remission, and 2 and 1 patient had no response. HBV reactivation occurred in 63.6% (14/22) and 36.8% (7/19) of patients (P = 0.047). The only significant difference in the study was in the probability of HBV reactivation between groups (P = 0.043, log-rank test). During follow-up, at least 1 relapse occurred in 46.7% (7/15) and 30.8% (4/13) of patients. Elevations in ALT were observed in 36.4% (8/22) and 26.3% (5/19) of patients, and the addition of lamivudine was required in 40.9% (9/22) and 21.1% (4/19) of patients. The most frequent adverse effects in both groups were infections (27.3% and 26.3%), followed by gastrointestinal symptoms (13.6% and 21.1%). Two MMF patients developed leukopenia. One patient in the prednisone group discontinued treatment because of severe hepatitis, and 1 patient in the MMF group discontinued because of severe pulmonary infection.
Conclusions: Among the adult Chinese patients with MSNS-HBV who completed this study, there were no significant differences in remission rates of idiopathic nephrotic syndrome between the standard prednisone regimen and the combination of MMF and a reduced prednisone dose. Rates of HBV reactivation, however, were significantly lower in the combination-therapy group.