title: PEG-asparaginase (Oncaspar) 2500 U/m(2) BSA in reinduction and relapse treatment in the ALL/NHL-BFM protocols.
abstract: OBJECTIVE
  As previous data had shown that only two-thirds of patients had the predicted activity time courses when PEG-asparaginase 1000 U/m(2) was used in reinduction after native E. coli asparaginase in induction treatment of acute lymphoblastic leukaemia (ALL), drug monitoring was performed with the use of a higher dose.
  
  
  METHODS
  Because one-third of patients had insufficient serum asparaginase activity time courses after a single dose of 1000 U/m(2) PEG-asparaginase during reinduction treatment, a dose of 2500 U/m(2) PEG-asparaginase, which is the approved dosage in Germany, was used in 39 reinduction and 20 relapse patients to determine whether prolongation of the activity time course may be possible with this higher dose, and to look for significant differences between reinduction and relapse patients.
  
  
  RESULTS
  After 1, 2 and 3 weeks, the mean activities were 1113 +/- 699 U/l, 231 +/- 259 U/l, and 13 +/- 35 U/l in the reinduction patients, and 1078 +/- 649 U/l, 165 +/- 195 U/l and 19 +/- 28 U/l in the relapse patients, respectively. There were a considerable number of patients with a substantially shortened activity time course in both groups. In 10 of 39 reinduction patients and in 7 of 24 doses during relapse treatment, only activities <100 U/l were found after 1 week with a further fast decline. No statistically significant differences between the two patient groups could be shown at any time-point.
  
  
  CONCLUSIONS
  Comparison of these data with activities after 1000 U/m(2) PEG-asparaginase showed no prolongation of the time with activity in the therapeutic range with the higher dose. Therefore, for a longer duration of therapeutic activity, administration of further doses is mandatory.
authors.affiliation: Department of Pediatric Hematology/Oncology, University of Münster, Germany. muellerb@mailer.uni-marburg.de
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Müller
authors.forename: Rita
authors.initials: R
authors.lastname: Beier
authors.forename: João Casimiro
authors.initials: JC
authors.lastname: da Palma
authors.forename: Claudia
authors.initials: C
authors.lastname: Lanvers
authors.forename: Elvira
authors.initials: E
authors.lastname: Ahlke
authors.forename: Volker
authors.initials: V
authors.lastname: von Schütz
authors.forename: Martin
authors.initials: M
authors.lastname: Gunkel
authors.forename: Alexander
authors.initials: A
authors.lastname: Horn
authors.forename: Martin
authors.initials: M
authors.lastname: Schrappe
authors.forename: Günter
authors.initials: G
authors.lastname: Henze
authors.forename: Karen
authors.initials: K
authors.lastname: Kranz
authors.forename: Joachim
authors.initials: J
authors.lastname: Boos
mesh_terms: D000293:Adolescent; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001215:Asparaginase / Q000493:pharmacokinetics / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000188:drug therapy*; D008297:Male; D011092:Polyethylene Glycols / Q000493:pharmacokinetics / Q000627:therapeutic use*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*; D012008:Recurrence
chemical_list: D000970:Antineoplastic Agents; D011092:Polyethylene Glycols; C042705:pegaspargase; D001215:Asparaginase