The efficacy of azacitidine for the treatment of high-risk myelodysplastic syndromes has prompted the issue of its potential role even in the treatment of acute myeloid leukemia (AML).
The authors analyzed 82 patients with AML who were diagnosed according to World Health Organization criteria. The median patient age was 72 years (range, 29-87 years), and 27 patients (33%) had secondary AML. Of 62 patients with evaluable cytogenetics, 18 patients (29%) had a poor-risk karyotype, and 44 patients (71%) had an intermediate karyotype. Thirty-five patients (43%) received azacitidine as front-line treatment, and 47 patients (57%) had previously received 1 or more line of chemotherapy.
The overall response rate was 32% (26 of 82 patients) and included 12 (15%) complete remissions (CRs), 4 (5%) CRs with incomplete blood count recovery (CRi), and 10 (12%) partial responses (PRs). Responses were observed more frequently among untreated patients compared with pretreated patients; in fact, 17 of 35 untreated patients (48%) responded, including 11 responses (31%) classified as CR/CRi. Conversely, only 9 of 47 pretreated patients (19%) responded, including 5 responses (11%) that were classified as CR/Cri. The response rate was significantly higher for untreated patients (P = .006) and those who had white blood cell counts <10 × 10(9) /L (P = .006). For untreated patients who achieved a response, the median overall response duration was 13 months, and the 1-year and 2-years overall survival rates were 58% and 24%, respectively.
The current results indicated that azacitidine promises to be an effective therapy for elderly patients with untreated AML and with white blood cell counts <10 × 10(9) /L.