Effect of Redosing Basiliximab in the Setting of Blood Loss in Heart Transplant Recipients on Infection and Rejection

Abstract

<h3>Purpose</h3> A prior study examining the pharmacodynamics of basiliximab in liver transplant recipients revealed significant medication clearance with blood loss. Dose escalation studies have shown total doses of 40-60 mg are effective and well-tolerated. We sought to examine infection risk when giving a total basiliximab dose of 40 mg vs 60 mg in our heart transplant (OHT) population in the setting of blood loss and requirement of massive transfusion protocol (MTP). <h3>Methods</h3> A single-center retrospective cohort study was performed examining adult OHT patients who received basiliximab induction therapy between June 1, 2010 and October 31, 2019. Cases and controls were matched 1:1. Patients were excluded if they were determined to be immunocompromised prior to transplant. The primary endpoint was incidence of infection. Secondary endpoints included the incidence of cell-mediated or antibody-mediated rejection, as well as the incidence of graft loss within 12 months. <h3>Results</h3> Forty-eight patients who underwent OHT were included, 24 patients in each group (40 mg and 60 mg total dose). Baseline characteristics were similar except for a higher number of LVAD patients in the 60 mg group (16.7% vs 45.8%, p=0.03). A total of 12 patients in the 40 mg group and 18 patients in the 60 mg group experienced at least one infection within 12 months after OHT, although this difference did not meet statistical significance (50% vs 75%, p=0.07). The types of infections were similar between the groups. A stepwise logistic regression showed blood loss and presence of LVAD at the time of transplant were predictors of infection occurrence. Delayed chest closure occurred more frequently in the basiliximab 60 mg group (p=0.002). Acute cellular rejection rates did not differ between groups (p=0.62). Antibody-mediated rejection occurred less frequently in the 40 mg vs 60 mg group (16.7% vs 50%, p=0.03). Two patients experienced graft loss in each group. <h3>Conclusion</h3> In our single-center retrospective study, the administration of an additional dose of basiliximab in the setting of MTP during OHT did not demonstrate a statistically significant increase in the risk of infection nor reduce the risk of rejection. The presence of LVAD at time of transplant was associated with an increased risk of infection and careful consideration should be given to these patients when selecting their induction regimen.