ASH 2022 | Treatment of intermediate-risk AML with gemtuzumab ozogamicin

We were interested to know whether patients with intermediate-risk acute myeloid leukemia benefited from the addition of gemtuzumab to standard 7 + 3 intensive chemotherapy. Although meta-analysis in the ALFA-0701 trial have demonstrated a small but palpably significant difference of 5.7% in overall survival, many of my colleagues are hesitant to add gemtuzumab to standard intensive chemotherapy because of fear of prolonged cytopenias, immuno-occlusive disease, particularly in the setting of subsequent allo-transplant.

We did a retrospective study looking at our experience of gemtuzumab 7 + 3 versus 7 + 3 alone in 113 patients with newly diagnosed intensively treated intermediate-risk AML. What we found in comparison of the two cohorts is that patients who received gemtuzumab ozogamicin had a significantly higher CR/CRh rate of 82% as opposed to 55%. Patients who had MRD testing demonstrated a significantly more MRD-negative CR/CRh and a trend towards potentially improved overall survival.

Of note, we noticed no veno-occlusive disease when patients went to transplant with prophylactic low dose heparin. We think that this may need to be more widely adopted in community practice as well as academic practices because of the potential benefits.

Lastly, we found some molecular markers. We saw that patients who’d responded well in the 7 + 3 GO group had more frequent NPM1 mutations and IDH1, IDH2 mutations, non-responders, more TET2, RUNX1, ASXL1, et cetera. So there may be ways to predict who might benefit from the third agent.