Adherence to oral medications during maintenance therapy

The COG AALL03N1 (NCT00268528) trial studied the impact of nonadherence to mercaptopurine during maintenance therapy in 327 children and adolescents (169 Hispanic patients and 158 non-Hispanic White patients).[99]

The COG AALL03N1 (NCT00268528) trial studied the impact of nonadherence to mercaptopurine during maintenance therapy in 327 children and adolescents (169 Hispanic patients and 158 non-Hispanic White patients).[99]

A progressive increase in relapse was observed with decreasing adherence to mercaptopurine, with HRs ranging between 4.0% to 5.7% for adherence rates ranging from 94.9% to 90%, 89.9% to 85%, and less than 85%. After adjusting for other prognostic factors (including NCI risk group and chromosomal abnormalities), a progressive increase in relapse was observed with decreasing adherence to mercaptopurine. MRD data were unavailable in this study population, so they were not included in the analysis of prognostic factors.

The COG AALL03N1 (NCT00268528) trial studied the impact of nonadherence to mercaptopurine during maintenance therapy in 327 children and adolescents (169 Hispanic patients and 158 non-Hispanic White patients).[99]

Adherence was significantly lower among Hispanic patients, patients older than 12 years, and patients from single-mother households. However, among adherent patients, Hispanic ethnicity remained an independent predictor of adverse outcome.

The AALL03N1 trial also included 71 Asian American patients and 68 African American patients, in addition to the non-Hispanic White and Hispanic patients described above.[100]

The AALL03N1 trial also included 71 Asian American patients and 68 African American patients, in addition to the non-Hispanic White and Hispanic patients described above.[100]

Using an adherence rate of less than 90% to define nonadherence, 20.5% of the participants were not adherent.

The AALL03N1 trial also included 71 Asian American patients and 68 African American patients, in addition to the non-Hispanic White and Hispanic patients described above.[100]

An adherence rate of less than 90% was associated with increased relapse risk (HR, 3.9).

The AALL03N1 trial also included 71 Asian American patients and 68 African American patients, in addition to the non-Hispanic White and Hispanic patients described above.[100]

Adherence rates were significantly lower in Asian American and African American patients than in non-Hispanic White patients.

In a third publication from the AALL03N1 study, the following key observations were made:[130]

In a third publication from the AALL03N1 study, the following key observations were made:[130]

Patients with mercaptopurine nonadherence (defined as mean adherence rate of <95%) were at a 2.7-fold increased risk of relapse compared with adherers.

In a third publication from the AALL03N1 study, the following key observations were made:[130]

Among adherers, high intra-individual variability in thioguanine levels (due to varying dose-intensity and drug treatment interruptions) was associated with increased risk of relapse.

The authors of the above studies also found that self-reporting was not a reliable measure of adherence, with 84% of patients overreporting compliance with taking mercaptopurine at least some of the time.[131] The data suggest that additional measures of adherence besides self-reporting are needed.

Another publication from the AALL03N1 study described mercaptopurine ingestion habits, red cell thioguanine nucleotide (TGN) levels, adherence, and relapse risk.[103]

Another publication from the AALL03N1 study described mercaptopurine ingestion habits, red cell thioguanine nucleotide (TGN) levels, adherence, and relapse risk.[103]

The findings showed that certain ingestion habits (e.g., taking with dairy and taking at varying times throughout the day) were associated with nonadherence. However, after adjusting for adherence and other prognostic factors, ingestion habits were not associated with relapse risk.

Another publication from the AALL03N1 study described mercaptopurine ingestion habits, red cell thioguanine nucleotide (TGN) levels, adherence, and relapse risk.[103]

For adherent patients, there was no association between TGN levels and ingestion habits.

Another publication from the AALL03N1 study described mercaptopurine ingestion habits, red cell thioguanine nucleotide (TGN) levels, adherence, and relapse risk.[103]

The authors concluded that commonly practiced restrictions surrounding mercaptopurine ingestion do not appear to impact outcome but may hinder adherence.