Therapeutic Effect of Combination Therapy with Rituximab and Intravenous Immunoglobulin on the Progression of Chronic Antibody Mediated Rejection

Abstract

While combination therapy of Rituximab (RTX) and intravenous immunoglobulin (IVIg) (RIT) has been proposed as therapeutic strategy for the treatment of chronic active antibody-mediated rejection (CAMR), its efficacy has not been established. In this study, we compared clinical outcome between the treatment group and historic control group to ascertain the efficacy of combination therapy for CAMR. Methods: Fifty-four patients diagnosed as CAMR from 2003 to 2013 were included in this study, among whom twenty-five were treated with RTX (375 mg/m2) and IVIg (0.4 g/kg) for 4 days (RIT group) and the remaining twenty-nine patients were regarded as historic control group. We assessed the change of allograft function before and after the diagnosis of CAMR in terms of the amount of decline in estimated glomerular filtration rate per month (ΔeGFR) and also investigated allograft survival rate after diagnosis of CAMR. Results: Neither of the two groups showed any significant differences with respect to clinical, historical and baseline characteristics including age at biopsy and gender. Nor did they show any remarkable differences on ΔeGFR and eGFR prior to and at the time of biopsy. However, ΔeGFR improved significantly to 0.02±1.3 mL·≡min-1·≡1.73m-2 per month 6 months after biopsy compared to that observed 6 months before RIT (1.33±1.21, p<0.05). Hence, Δ eGFR post-Bx was significantly lower in treatment group compared to that of historic control group. Moreover allograft survival rate after biopsy was significantly higher in treatment group at 3 years from the diagnosis of CAMR. Conclusion: In CAMR, RIT could be proposed as a promising regimen in terms of delaying the progression of CAMR and better allograft survival rate compared to HC group.