Two recently published studies added to our knowledge on the clinical benefit of gemtuzumab in patients with AML. The first study by Bouvier A et al demonstrated no survival benefit with the addition of gemtuzumab in patients with intermediate risk AML. The second study by Duncan et al was a retrospective study by the CIBMTR. That study demonstrated increased risk of VOD in pediatric patients who received gemtuzmab. However, overall survival and event free survival was similar in both groups. These results highlight the need for increased awareness post-transplant for the possibility of VOD, and also reduces concern regarding overall survival for patients receiving gemtuzumab.
Another study by the EBMT ( Debaja et al ) evaluated factors affecting the outcome of patients with AML receiving a second allogeneic HCT. Outcome was worse for patients not in CR and those with a short time from allo-HCT. Overall survival was similar for patients receiving a MUD or haploidentical donor. Two year overall survival was 31% vs. 29% for patients receiving MUD vs. haploidentical allo-HCT. This study clearly expands options for patients receiving a second allo-HCT. In addition, a prior study by EBMT demonstrated no difference in overall survival between patients receiving same vs. different vs. haplo donor.
Finally, a large study by the CIBMTR ( Percival et al ) demonstrated that in AML patients, achieving CRi and having persistent MRD prior to transplantation were associated with worse outcome compared to CR with no evidence of MRD. The adjusted 5 year survival for patient with CR/MRD-ve, CR/MRD+ve, CRi/MRD-ve and CRi/MRD+ve was 52%, 37%, 44% and 34% respectively.