Gemtuzumab ozogamicin as first-line treatment in patients aged 70 years or older with acute myeloid leukemia.

Background: Elderly patients with acute myeloid leukemia (AML) are generally unable to withstand the rigors of intensive induction chemotherapy and its attendant complications. Gemtuzumab ozogamicin (GO) is an immunoconjugate that had demonstrated activity in recurrent AML.

Methods: The objective of the current study was to determine the prognostic factors for achievement of complete remission (CR) in newly diagnosed elderly AML patients treated with GO as initial induction therapy. A retrospective study was performed of efficacy and toxicity associated with GO therapy, and factors potentially predictive of response were assessed in 49 previously untreated AML patients.

Results: CR was achieved in 14% of all treated patients. Among the patients with an intermediate-risk karyotype, the CR rate was 30%, compared with none with an unfavorable karyotype. The median duration of overall survival was 3.7 months (95% confidence interval [95% CI], 1.4-6.9 months), and the median recurrence-free survival in patients who achieved CR was 11.8 months (95% CI, 5.0-ind months).

Conclusions: These data suggest that GO should be considered as a first-line treatment option in older patients with AML with intermediate-risk cytogenetics who cannot tolerate high-dose induction chemotherapy.