Study to Assess Compliance With Long-Term Mercaptopurine Treatment in Young Patients With Acute Lymphoblastic Leukemia in Remission

RATIONALE: Assessing why young patients who have acute lymphoblastic leukemia may not take their medications as prescribed may help identify ways to assist them in taking their medications more consistently and may improve long-term treatment outcomes.

PURPOSE: This clinical trial is assessing compliance with long-term mercaptopurine treatment in young patients with acute lymphoblastic leukemia in remission.

OBJECTIVES:

Primary

• Determine and compare adherence to maintenance mercaptopurine using the following assessments: serial red cell mercaptopurine metabolites (i.e., 6TGN and methylTIMP), frequency of mercaptopurine dosing using an electronic pill monitoring system (MEMS^®), and self-report of adherence to mercaptopurine by questionnaire in a cohort of younger patients with acute lymphoblastic leukemia in first remission who belong to four different ethnic and racial groups (Caucasians, African-Americans, Hispanics, and Asians).
• Determine the impact of adherence to mercaptopurine on event-free-survival (EFS) in the entire cohort, after adjusting for known predictors of disease outcome.
• Define a critical level of adherence that has a significant impact on EFS for the entire cohort.
• Describe prevalence of adherence to mercaptopurine by ethnicity.
• Describe behavioral and sociodemographic predictors of adherence.
• Describe the pill-taking practices in this cohort.
• Evaluate the impact of adherence on ethnic/racial difference in EFS.

Secondary

• Assess the concordance among 6TGN and methylTIMP levels, electronic pill monitoring, and self-reported adherence in the ethnic/racial groups.

OUTLINE: This is a multicenter study.

Patients* receive an electronic pill monitoring system comprising an empty MEMS^® medication bottle with TrackCap™ child resistant (CR). The mercaptopurine prescription is filled using this system. Beginning on day 1 of the third or later course of maintenance therapy, patients take all doses of mercaptopurine from the MEMS^® medication bottle with TrackCap™ CR for at least 6 months. The MEMS^® TrackCap™ CR is mailed to the study center at the end of study. Patients also receive oral methotrexate as indicated by their individual chemotherapy regimen.

NOTE: *Study closed to accrual for Caucasian and Hispanic patients as of 8/14/2009.

Blood samples are collected on days 1, 29, 57, 85, 113, 141, and 169. Patient or caregiver completes demographic questionnaire on day 29. Patient and/or caregiver completes a self-reported adherence questionnaire on days 29, 57, 113, and 141.

After completion of study treatment, patients are followed periodically.

PROJECTED ACCRUAL: A total of 720 patients will be accrued for this study.

• Behavioral: compliance monitoring
• Drug: mercaptopurine
• Drug: methotrexate
• Other: study of socioeconomic and demographic variables

DISEASE CHARACTERISTICS:

• Diagnosis of acute lymphoblastic leukemia (ALL) at ≤ 21 years of age

  • Disease in first remission

• Receiving self- or parent/caregiver-administered oral antimetabolite chemotherapy during the maintenance phase of therapy

  • Has completed at least two courses* of maintenance chemotherapy, and is scheduled to receive at least two more planned courses of maintenance chemotherapy NOTE: *A course is defined as 12 weeks/84 days of maintenance chemotherapy.

    • Treatment plan must include oral mercaptopurine (6-MP) at 75 mg/m^2/day and oral methotrexate at 20 mg/m^2/week during the maintenance phase

      • Dose modification of 6-MP or methotrexate based on laboratory or clinical parameters is acceptable

PATIENT CHARACTERISTICS:

• Belongs to one of the four following ethnic/racial categories: African-American, Asian, Caucasian*, or Hispanic* NOTE: Closed to accrual for Caucasian and Hispanic patients as of 8/14/2009.

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• Concurrent enrollment on another therapeutic study for ALL allowed