#1006 Basiliximab induction alone vs. a dual ATG-basiliximab approach in first living non-sensitized renal transplant recipients with reduced HLA matching

Abstract Background and Aims Individualizing induction therapy based on immunological risk is crucial for optimizing outcomes in kidney transplantation. Due to the prevalent utilization of living unrelated donor (LURD) transplants in Israel , a substantial proportion of non-sensitized recipients have a reduced level of HLA matching (5–6 HLA mismatch). Our observations revealed a heightened acute rejection rate in this particular population when employing basiliximab induction. In response to this, we have modified our induction protocol, opting for a combination of single ATG dose and basiliximab. The primary objective was to diminish the incidence of acute rejection, and notably, we have significantly decreased the ATG dosage to mitigate the potential adverse effects associated with higher doses of ATG. In this study, we compare the 6-month outcomes between basiliximab induction alone and a dual ATG-basiliximab approach in this population. Method A retrospective analysis included 157 first living non-sensitized renal transplant recipients (RTRs). Within this cohort, 96 individuals exhibited low HLA matching (5–6 HLA mismatches). The low HLA match subgroup was categorized into 52 RTRs receiving basiliximab alone and 44 recipients treated with a combined single ATG dose of 1.5 mg/kg and basiliximab. The primary endpoint was early acute cellular rejection (ACR) within 6 months post-transplant while secondary outcomes encompassed infection rates, renal allograft function, length of stay (LOS), and overall admissions. Results Transitioning from basiliximab to combined ATG-basiliximab reduced early ACR (from 23.1% to 9.1%, P = 0.067). Age was a predictor for rejection, and subgroup analysis showed consistent rejection reduction across age groups. No significant differences were observed in admission for transplant LOS or in peri-operative complications, nor in infections rate including BK and CMV viremia, allograft function and number of admissions up to 6 months post-transplant. Conclusion In non-sensitized first living RTRs with reduced HLA matching, a dual single ATG-basiliximab induction approach significantly reduced early ACR without compromising safety.