Induction therapy determines graft and patient survival in ABO-incompatible kidney transplantation

A.E. de Weerd, J.A.J.G. van den Brand, H. Bouwsma, A.P.J. de Vries, P.H.M.M. Dooper, J.S.F. Sanders, M. van Dijk, M.H.L. Christiaans, F.E. van Reekum, A.D. van Zuilen, F.J. Bemelman, M.S. van Sandwijk, S.A. Nurmohamed, M. van Agteren, M.G.H. Betjes, M.F.C. de Jong, M.C. Baas

Thursday 5 march 2020

14:40 - 14:50h at Leo Franssen zaal

Parallel session: Parallel sessie XIV– Klinische abstracts

Background: Rituximab is the standard induction agent for ABO-incompatible (ABOi) kidney transplantation. Alternative regimens are basiliximab on top of rituximab and alemtuzumab. We compared graft and patient survival in ABOi transplant recipients according to three different induction regimens, with ABO-compatible (ABOc) transplant recipients.

Methods: Data on all kidney transplantations performed since the first ABOi transplantation were obtained from the Dutch Organ Transplant Registry till March 2019. Outcomes for ABOi, ABOc living and ABOc deceased donor transplantations were recorded. Using propensity scores, ABOi recipients were matched to ABOc living donor recipients and deceased donor recipients and in a 1:4 ratio. The propensity score model included transplant center, recipient age, number of transplantations, peak panel-reactive antibodies (PRA) and dialysis duration. For comparison, ABOi recipients were divided in three groups according to induction therapy: rituximab, rituximab/basiliximab and alemtuzumab. Propensity matched survival was analyzed both with the total ABOi cohort and after excluding the rituximab group.

Results: 11.706 Kidney transplantations were performed between March 2006 and March 2019, of which 302 ABOi procedures. If patients received a second ABOc kidney allograft in this period, only the first ABOc transplantation was included. 8579 individual ABOc recipients were identified. Induction therapies in ABOi recipients consisted of rituximab alone (43%), rituximab with basiliximab (20%), alemtuzumab (33%) or other (4%). After matching, baseline characteristics for the ABOi compared to the ABOc-living donor group were: recipient mean age 54 vs 55 years, donor mean age 55 vs 54 years, mean total HLA mismatches 3.5 vs 3.5, peakPRA 4% in both groups and retransplant 17% vs 5%. 66% of ABOi recipients were blood group O. ABOi recipients had a higher risk of death-censored graft failure compared to ABOc living donor recipients (HR=2.68, 95%CI 1.71-4.19). After excluding the rituximab group, both rituximab/ basiliximab and alemtuzumab treated recipients had similar graft and patient survival compared to their propensity matched ABOc controls (Cox regression data by induction therapy will be available by early 2020).

Conclusions: Both rituximab/basiliximab and alemtuzumab induction are superior to rituximab alone therapy for ABOi kidney transplantation. With these induction agents graft and patient survival after ABOi kidney transplantation are similar to ABOc controls.