Prior Gemtuzumab Ozogamicin Exposure in Adults with Acute Myeloid Leukemia Does Not Increase Hepatic Veno-Occlusive Disease Risk after Allogeneic Hematopoietic Cell Transplantation: A Center for International Blood and Marrow Transplant Research Analysis

Gemtuzumab ozogamicin (GO) therapy before allogeneic hematopoietic cell transplantation (alloHCT) has been historically associated with an increased risk of hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) in patients with acute myeloid leukemia (AML). The current analysis examined VOD/SOS risk and outcomes in a cohort of patients who in recent years were reported to the Center for International Blood and Marrow Transplant Research. Adults with AML who had GO exposure before myeloablative alloHCT were matched 1:4 by age and disease status at transplant to recipients without GO exposure (control subjects). One hundred thirty-seven patients with GO exposure and 548 matched control subjects who underwent alloHCT between 2008 and 2011 were included in this analysis. With a median ∼8-year follow-up of survivors, the 5-year overall survival probability was similar in the 2 cohorts: 38% and 38% in the GO-exposed versus control groups (P = .97). Incidence of VOD/SOS and severe VOD/SOS, respectively, at 100 days was 4% (95% confidence interval [CI], 1% to 7%) and 3% (95% CI, 1% to 6%) in GO-exposed patients and 3% (95% CI, 2% to 5%) and 1% (95% CI, 0% to 2%) in control subjects. Correspondingly, among patients who developed VOD/SOS, 1-year survival probability after VOD/SOS diagnosis was 33% (95% CI, 5% to 72%) and 27% (95% CI, 11% to 47%; P = .78). In multivariate analyses, GO exposure before alloHCT was not associated with an increased risk of VOD/SOS (odds ratio, 1.10; P = .85) or death (hazard ratio, 1.08; P = .57). Three deaths (3%) in the GO group and 3 deaths (<1%) in the control group were attributed to VOD/SOS. Our results suggest that GO treatment before myeloablative alloHCT in the recent era is not associated with an increased risk of post-transplant VOD/SOS or death.