Interleukin-2 after autologous stem-cell transplantation for adult patients with acute myeloid leukemia in first complete remission.
OBJECTIVE
To determine the disease-free survival (DFS) and toxicity of administering interleukin-2 (IL-2) immunotherapy early after autologous stem-cell transplantation (ASCT) to simulate a graft versus leukemia effect observed in allogeneic transplantation.


METHODS
Fifty-six patients with acute myeloid leukemia in first remission received a single consolidation of high-dose cytarabine-idarubicin at a median of 1.1 month postremission with the intent to proceed to ASCT and IL-2 9 x 10(6) U/m(2)/24 h for 4 days, followed by 10 days of IL-2 1.6 x 10(6) U/m(2)/24 h on hematologic recovery.


RESULTS
Eighty-four percent of patients received the intended ASCT, and 68% of patients received IL-2 treatment. With a median follow-up of 39.4 months (range, 1.2 to 76.3 months), the 2-year cumulative probability of DFS for all 56 patients is 68% (95% confidence interval [CI], 55% to 80%) and 74% (95% CI, 57% to 85%) for the 39 patients undergoing IL-2 treatment after ASCT. The 2-year cumulative probability of DFS for favorable, intermediate, and unfavorable cytogenetics is 88% (95% CI, 59% to 97%), 48% (95% CI, 26% to 67%), and 70% (95% CI, 23% to 93%), respectively. Toxicities from IL-2 were mainly thrombocytopenia, leukopenia, fever, and fluid retention. Two septic deaths occurred during neutropenia, which includes one during consolidation and one during transplant, for an overall 4% mortality rate.


CONCLUSIONS
These results suggest that a moderate dose of IL-2 after high-dose cytarabine-idarubicin-mobilized ASCT is associated with a low regimen-related toxicity and may improve DFS. A phase III study of IL-2 is now warranted.
Stein
Anthony S
AS
Division of Hematology and Bone Marrow Transplantation, City of Hope National Medical Center, 1500 East Duarte Road, Duarte, CA 91010, USA. astein@coh.org
O'Donnell
Margaret R
MR
Slovak
Marilyn L
ML
Snyder
David S
DS
Nademanee
Auayporn P
AP
Parker
Pablo
P
Molina
Arturo
A
Somlo
George
G
Fung
Henry C
HC
Krishnan
Amrita
A
Rodriguez
Roberto
R
Spielberger
Ricardo T
RT
Wang
Shirong
S
Dagis
Andrew
A
Vora
Nayana
N
Arber
Daniel A
DA
Niland
Joyce C
JC
Forman
Stephen J
SJ
D000328:Adult; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D016001:Confidence Intervals; D003561:Cytarabine / Q000008:administration & dosage; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D015255:Idarubicin / Q000008:administration & dosage; D007376:Interleukin-2 / Q000009:adverse effects / Q000627:therapeutic use*; D007951:Leukemia, Myeloid / Q000188:drug therapy* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D033581:Stem Cell Transplantation
D000970:Antineoplastic Agents; D007376:Interleukin-2; D003561:Cytarabine; D015255:Idarubicin