Improved survival in AML with higher anthracycline doses
Younger patients with acute myeloid leukemia (AML) that receive higher doses of anthracyclines during induction chemotherapy are reported to have better complete remission rates in most studies. As of yet, studies have failed to show an improved surivival when compared to the standard doses of the “7 and 3” regimen. This article reviews the results of a new randomized controlled trial exploring the effects of higher doses of anthracyclines on overall survival.
Younger patients with acute myeloid leukemia (AML) that receive higher doses of anthracyclines during induction chemotherapy are reported to have better complete remission rates in most studies. As of yet, studies have failed to show an improved surivival when compared to the standard doses of the “7 and 3” regimen. This article reviews the results of a new randomized controlled trial exploring the effects of higher doses of anthracyclines on overall survival.
With the exception of the use of all trans-retinoic acid (ATRA) for patients
with acute pro-myelocytic leukemia (APL), relatively few changes in the therapy
of acute myeloid leukemia (AML) have been made since the introduction of the
so-called “7 and 3” regimen in 1973.1, 2 The regimen is made up of 3
daily doses of daunorubicin at a dose of 45 mg/m2 combined with cytarabine for
seven continuous daily doses at 100 mg/m2.1, 2
The outcome to current therapy is suboptimal with only 60-70% of patients
achieving their first complete remission. The median survival of patients who
achieve remission is 12-24 months and the five year survival is achieved in only
20% of those patients.3 Attempts to find a superior alternative or
improve the 7 and 3 induction regimen have been disappointing.4, 5
Both, the intensification of cytarabine dose6-8 and the addition of
other drugs, have failed to improve outcome when compared to “7 and
3”.9
That all changed this week, with the publication of the first conclusive
evidence for better overall survival in patients receiving higher doses of
daunorubicin (90 mg/m2) compared to the conventional dose (45 mg/m2) regimen.
The Eastern Cooperative Oncology Group (ECOG) study, which appears this week in
the New England Journal of Medicine,10 assigned 657 patients between
the ages of 17 and 60 years with newly diagnosed AML to receive either the 7 and
3 induction regimen with conventional dose of daunorubicin versus the higher
dose. Those that achieved a complete remission were then given post remission
therapy according to their risk stratification as well as the availability of an
HLA matched sibling. Patients with unfavorable or intermediate risk profile were
offered allogeneic transplant if they had an HLA matched sibling.11,
12 The remainder were offered high dose cytarabine with or without
gemtuzumab ozgamicin, followed by an autologous transplant.13
An intention to treat analysis, with a median follow up of 25.2 months,
revealed that 90 mg/m2 daunorubicin resulted in higher complete remission rates
(70.6% vs. 57.3%, P=0.001) as well as improved median survival (23.7
vs. 15.7 months, P=0.003).
Interestingly, the rates of serious (grade 3 to 5) adverse events were
similar in the two groups. Serious cardiac toxicity was observed in 7.2% in the
standard dose arm compared to 7.9% in the high dose arm. A reduced left
ventricular ejection fraction was observed in 1.3% of patients in the high dose
group and none of the standard regimen group. The rate of treatment related
mortality was 4.5% in the standard arm compared to 5.5% in the high dose arm
(P=0.60). The most common cause of death was from infections and
pulmonary failure.Results
For those patients with a favorable cytogenetic profile that received the high dose, the median survival had not been reached at the time of the final analysis (median follow up of 25.2 months); thus, exceeding the current median survival of 12-24 months in patients who achieve remission.3 The largest difference was seen in those with intermediate risk who received the daunorubicin 90 mg/m2. Patients with unfavorable cytogenetic profile, however, did not experience any benefit from higher doses.Conclusion
Patients with low and intermediate risk de novo AML should be offered 7 and 3 induction therapy with daunorubicin dose intensification at 90 mg/m2. This is both safe and effective in these patients but not associated with any benefit in patients with poor prognostic features. However, as the authors note, it is not yet clear what the optimal dose of intensification is. Whether 90 mg/m2 is better than 60 mg/m2, requires further study.Conflict of interest statement
No financial conflicts or disclosures to report.
CITE THIS ARTICLE:
Tamer M. Fouad, M.D.. Improved survival in AML with higher anthracycline doses. Doctors Lounge Website. Available at: http://www.doctorslounge.com/index.php/articles/page/300. Accessed April 01 2012.
Tamer M. Fouad, M.D.. Improved survival in AML with higher anthracycline doses. Doctors Lounge Website. Available at: http://www.doctorslounge.com/index.php/articles/page/300. Accessed April 01 2012.
