Prior treatment with gemtuzumab ozogamicin and the risk of veno-occlusive disease after allogeneic haematopoietic stem cell transplantation.

This was a retrospective multicenter study including 44 acute leukaemia patients who have received allogeneic haematopoietic SCT (allo-HSCT) after prior exposure to Gemtuzumab Ozogamicin (GO) + chemotherapy. Median interval between last administration of GO and allo-HSCT was 4.2 (range, 0.8-26.3) months. At time of allo-HSCT, 33 patients were in CR. The majority of patients (n=36) received a reduced-intensity conditioning (RIC) regimen before allo-HSCT. All but one patient received low-dose heparin for veno-occlusive disease (VOD) prophylaxis. With a median follow-up of 15 (range, 1.1-63) months, overall survival and disease-free survival after allo-HSCT were 45% (95% confidence interval (CI), 30-61%) and 38% (95% CI, 24-54%) at 2 years, respectively. The cumulative incidence of grade 3-4 hyperbilirubinemia was 13.5% (n=6), with this being 21% in patients with a short (< or =3.5 months) GO-allo-HSCT interval (n=4/19) vs 8% in all others (P=NS). Overall, the cumulative incidence of VOD was 7% (n=3), with this being 10.5% (n=2/19) in patients with a short GO-allograft interval (< or =3.5 months) vs 4% (n=1/25) for all others (P=NS), and 5.5% (n=2/36) in patients receiving an RIC regimen vs 12.5% for the others (n=1/8) (P=NS). These results suggest that GO-based chemotherapy before allo-HSCT is feasible and does not result in an excessive rate of liver toxicity, especially VOD, after allo-HSCT.