title: Combination therapy with methotrexate, vincristine, polyethylene-glycol conjugated-asparaginase, and prednisone in the treatment of patients with refractory or recurrent acute lymphoblastic leukemia.
abstract: BACKGROUND
  L-asparaginase in combination with methotrexate has synergistic antileukemic activity in a schedule-dependent fashion. A new preparation of L-asparaginase, polyethylene-glycol conjugated (PEG)-asparaginase, is a pharmacologically different formulation of L-asparaginase with distinct properties including a longer half-life and less immunogenic properties.
  
  
  METHODS
  Patients with refractory or recurrent acute lymphoblastic leukemia (ALL) were treated with a combination of methotrexate (MTX), vincristine, PEG-asparaginase, and prednisone (MOAP). The treatment was comprised of MTX, 100 mg/m(2) intravenously (i.v.), over 15 minutes on Days 1 and 14; PEG-asparaginase, 2500 IU/m(2), with a maximum dose of 3750 IU i.v. approximately 4-6 hours after MTX on Days 1 and 14; vincristine, 1.4 mg/m(2) (maximum dose, 2 mg) i.v., over 15 minutes on Days 1, 7, and 14; and prednisone, 200 mg daily orally, on Days 1-5 and 14-19.
  
  
  RESULTS
  Thirty-two patients with a median age of 34 years (range, 20-74 years) were treated. Eight patients (25%) had ALL that was refractory to prior therapy and 24 patients (75%) had recurrent disease. Seven patients (22%) achieved a complete remission (CR). Five patients (16%) died early due to infections. Features associated with a poor response were high pretreatment lactate dehydrogenase levels and Philadelphia chromosome positive disease. The median duration of CR was 16 weeks and the overall median survival after MOAP therapy was 12 weeks. Anaphylactic reactions were not observed during MOAP combination therapy.
  
  
  CONCLUSIONS
  MOAP is an active regimen in patients with refractory or recurrent ALL. This regimen is well tolerated and is not associated with allergic reactions. However, further studies regarding the pharmacologic interaction of MTX with PEG-asparaginase are needed to optimize this regimen.
authors.affiliation: The Department of Leukemia, The University of Texas, M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
authors.forename: A
authors.initials: A
authors.lastname: Aguayo
authors.forename: J
authors.initials: J
authors.lastname: Cortes
authors.forename: D
authors.initials: D
authors.lastname: Thomas
authors.forename: S
authors.initials: S
authors.lastname: Pierce
authors.forename: M
authors.initials: M
authors.lastname: Keating
authors.forename: H
authors.initials: H
authors.lastname: Kantarjian
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage* / Q000633:toxicity; D001215:Asparaginase / Q000008:administration & dosage; D004334:Drug Administration Schedule; D004800:Enzymes, Immobilized / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage; D008875:Middle Aged; D010677:Philadelphia Chromosome; D011092:Polyethylene Glycols / Q000008:administration & dosage; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy* / Q000401:mortality; D011241:Prednisone / Q000008:administration & dosage; D012008:Recurrence; D012074:Remission Induction; D016896:Treatment Outcome; D014750:Vincristine / Q000008:administration & dosage
chemical_list: D004800:Enzymes, Immobilized; D011092:Polyethylene Glycols; D014750:Vincristine; C042705:pegaspargase; D007770:L-Lactate Dehydrogenase; D001215:Asparaginase; D011241:Prednisone; D008727:Methotrexate