Impact of rituximab therapy for treatment of acute humoral rejection

Antibody mediated rejection (AMR) is associated with a greater incidence of allograft loss because traditional approaches - pulse steroid or anti-lymphocyte antibodies are usually ineffective. This retrospective analysis documented the benefit of rituximab administration in addition to plasmapheresis (PP). Methods: We retrospectively reviewed the data from 54 kidney transplant patients treated for AMR between 2001 and 2006, including 26 patients who received PP plus rituximab (Group A), versus 28 subjects who underwent PP without rituximab (Group B). Only patients whose serum IgG levels were below normal values received intravenous gamma globulin (IVIG). In addition to clinical and demographic variables we evaluated graft/patient survivals at two years post-diagnosis, Banff classification of rejections, serum creatinine and calculated GFR values at baseline, rejection, resolution as well as three, six, 12 and 24 months thereafter. Results: The demographic features of the cohorts showed no significant differences. The two-year graft survival for patients treated with rituximab plus PP was 90%, significantly better than 60% in the PP cohort (p=0.005). Upon multivariate analysis administration of rituximab was the most significant factor (≥0.009); whereas, IVIG also produced a useful effect (p=0.05). Neither the mean (≥0.42) nor the slope (p=0.25) of GFR values showed a significant difference among salvaged kidneys over 24 months after completion of AMR treatment. The rates and types of infectious complications at three and six months did not show significant differences or impact on graft survival. Conclusion: Addition of rituximab improved the outcomes of PP treatment of antibody mediated rejection episodes.