EBMT 2018 | MAC versus RIC allo-HCT in patients with AML in CR2

Maria H. Gilleece, from Leeds Cancer Institute, Leeds, UK, presented at the 44^th Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT), data from a retrospective study by the Acute Leukemia Working Party (ALWP) of the EBMT, which compared the impact of myeloablative (MAC) versus reduced intensity (RIC) conditioning on transplant outcomes in different age groups of a large cohort of acute myeloid leukemia (AML) patients in second complete remission (CR2).

In total, 1,879 AML patients in CR2 who received MAC (n = 1,010, median age at transplant = 42.8 years) or RIC (n = 869, median age at transplant = 57.3 years) between 2007–2016 were identified from the EBMT registry and analyzed in this retrospective study.

Key findings:

• Outcomes in all patients
  • 2-year leukemia free survival (LFS): 52% (95% CI, 49.5–54.5)
  • 2-year overall survival (OS): 58.7% (95% CI, 56.2–61.2)
  • 2-year relapse incidence (RI): 28.9% (95% CI, 26.7–31.2)
  • 2-year non relapse mortality: 19% (95% CI, 17.2–21)
  • 2-year graft versus host disease (GvHD) relapse free survival (GRFS): 38.7% (95% CI: 36.2–41.1)
  • 2-year chronic GvHD: 37.2%
• In patients aged ≥ 50 years, compared to MAC, RIC decreased NRM (HR = 0.535, P = 0.0004) with worse cGVHD (HR = 1.377, P = 0.03) but no impact on RI, LFS, GFRS or OS.
• RIC and MAC had similar outcomes in patients < 50 years

The speaker, Maria Gilleece, concluded by noting that “allo-HCT rescues more than 50% of AML patients achieving CR2 post-relapse”. Additionally, the findings of this retrospective study demonstrate that in AML patients in CR2, “RIC allo-HCT reduces procedural mortality in patients ≥ 50 years without increasing RI and provides equivalent outcomes to MAC allo-HCT in patients < 50 years”. She further added that the findings of this study should be confirmed in a prospective study.