title: Cytarabine dose for acute myeloid leukemia.
abstract: BACKGROUND
  Cytarabine (ara-C) is an important drug in the treatment of acute myeloid leukemia (AML). High-dose cytarabine (2000 to 3000 mg per square meter of body-surface area) is toxic but results in higher rates of relapse-free survival than does the conventional dose of 100 to 400 mg per square meter. Intermediate dose levels have not been thoroughly evaluated.
  
  
  METHODS
  We compared two induction regimens in patients 18 to 60 years of age (median, 49) who had newly diagnosed AML. The intermediate-dose group, totaling 431 patients, received cytarabine at a dose of 200 mg per square meter given by continuous intravenous infusion for 24 hours during cycle 1 of induction therapy and 1000 mg per square meter by infusion for 3 hours twice daily during cycle 2 of induction therapy. The high-dose group, totaling 429 patients, received a dose-escalated regimen of 1000 mg of cytarabine per square meter every 12 hours in cycle 1 and 2000 mg per square meter twice daily in cycle 2. Patients with a complete response did not receive additional cytarabine but received consolidation therapy in a third cycle of chemotherapy (mitoxantrone-etoposide) or underwent autologous or allogeneic stem-cell transplantation. Complete remission rates, survival rates, and toxic effects were assessed for each treatment group.
  
  
  RESULTS
  At a median follow-up of 5 years, no significant differences were noted between the intermediate-dose group and the high-dose group with respect to complete remission rates (80% and 82%, respectively), probability of relapse, event-free survival at 5 years (34% and 35%), or overall survival (40% and 42%). High-dose cytarabine provided no clear advantage in any prognostic subgroup. The high-dose treatment resulted in higher incidences of grade 3 and grade 4 toxic effects (in cycle 1), prolonged hospitalization, and delayed neutrophil recovery (in cycle 2) and platelet recovery (in cycles 2 and 3).
  
  
  CONCLUSIONS
  Induction therapy with cytarabine at the lower dose already produced maximal antileukemic effects for all response end points, suggesting a plateau in the dose-response relationship above this dose level. High-dose cytarabine results in excessive toxic effects without therapeutic benefit. (Netherlands Trial Register number, NTR230.).
authors.affiliation: Erasmus University Medical Center, Department of Hematology (L413), P.O. Box 2040, 3000 CA Rotterdam, the Netherlands. b.lowenberg@erasmusmc.nl
authors.forename: Bob
authors.initials: B
authors.lastname: Löwenberg
authors.forename: Thomas
authors.initials: T
authors.lastname: Pabst
authors.forename: Edo
authors.initials: E
authors.lastname: Vellenga
authors.forename: Wim
authors.initials: W
authors.lastname: van Putten
authors.forename: Harry C
authors.initials: HC
authors.lastname: Schouten
authors.forename: Carlos
authors.initials: C
authors.lastname: Graux
authors.forename: Augustin
authors.initials: A
authors.lastname: Ferrant
authors.forename: Pieter
authors.initials: P
authors.lastname: Sonneveld
authors.forename: Bart J
authors.initials: BJ
authors.lastname: Biemond
authors.forename: Alois
authors.initials: A
authors.lastname: Gratwohl
authors.forename: Georgine E
authors.initials: GE
authors.lastname: de Greef
authors.forename: Leo F
authors.initials: LF
authors.lastname: Verdonck
authors.forename: Martijn R
authors.initials: MR
authors.lastname: Schaafsma
authors.forename: Michael
authors.initials: M
authors.lastname: Gregor
authors.forename: Matthias
authors.initials: M
authors.lastname: Theobald
authors.forename: Urs
authors.initials: U
authors.lastname: Schanz
authors.forename: Johan
authors.initials: J
authors.lastname: Maertens
authors.forename: Gert J
authors.initials: GJ
authors.lastname: Ossenkoppele
mesh_terms: D000293:Adolescent; D000328:Adult; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage* / Q000009:adverse effects; D003131:Combined Modality Therapy; D003561:Cytarabine / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D057194:Intention to Treat Analysis; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy* / Q000401:mortality / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012074:Remission Induction; D033581:Stem Cell Transplantation; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D000964:Antimetabolites, Antineoplastic; D003561:Cytarabine