Conditions: Leukemia, Lymphocytic, Acute
Keywords: Leukemia, Lymphocytic, Acute [C04.557.337.428.511] 6-mercaptopurine methotrexate asparaginase
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 38
Healthy volunteers: no

Brief summary:
The present pharmacokinetic (PK)-pharmacodynamic (PD) study will explore the toxicity and antileukemic response during the initial 3 months of individualised therapy of children and young adults with acute lymphoblastic leukemia (ALL). The investigators will on an individual toxicity-titrated basis attempt to increase the dose intensity of the 6-mercaptopurine used in the two-months post-remission treatment phase of lower risk childhood ALL. This will be performed together with continuous PEG-ASP (every 2nd week) and interspersed HD-MTX (5 g/m\^2) every 3rd week. Thus, the trial will also test the feasibility of this particular drug combination.

Detailed description:
In addition to the details above we will also explore

* the relationship of the post-HD-MTX MRD-levels with the dose of 6MP, TPMT-activity, DNA-6TGN, E-6TGN, E-MeMP, E-MTX, and presence of ASP-antibodies,
* the early development of anti-ASP antibodies during continuous PEG-ASP therapy.

The study could improve the understanding of the pharmacodynamics of the 6MP/HD-MTX interaction in combination with PEG-ASP.

Arms:
arm 1: All patients received basic daily 6MP (6-mercaptopurine) (25 mg/m\^2) and in addition high-dose methotrexate(HDM) every 3rd week (3 times HDM in total) and PEG-asparaginase every 14th day. Patients increased the dose of 6MP 2 weeks after each HDM if if the myelotoxicity had been acceptable. This means 2 increments since the study stopped 2 weeks after the last HDM

Interventions: intervention 1: 6-mercaptopurine
Intervention descriptions: intervention 1: Standard dose 25 mg/m\^2/day. Can be increased up to 75 mg/m\^2/day if the myelosuppression is acceptable (ANC\>0.5 T-count \>50)

Protocol document: