[Early non-compliance with oral anticancer drugs, a clinical pharmacy as key issue in onco-senology]

The assessment of adherence is necessary to ensure therapeutic compliance, particularly with oral anti-cancer drugs (OACs). Already easily implemented, the nationally validated GIRERD questionnaire seems incomplete for assessing adherence. We set out to study and characterize adherence in a cohort of patients treated with OACs, using 2 questionnaires.

The evaluation was carried out in patients treated with OAC using the GIRERD questionnaire, composed of 6 items, and an institutional questionnaire consisting of 7 items; with a common gradation based on that of the GIRERD score. These questionnaires were submitted within the first 3 months of ribociclib (OAC) initiation, in women with metastatic hormone-dependent breast cancer.

Of the 50 evaluable patients, around 60% had a score above 0 (poorly observant [PO]+unobservant [UO]) according to the 2 questionnaires during this study. UO patients represent 6% according to the GIRERD score and 16% according to the institutional score. The main causes of non-adherence were late dosing (21/50) and forgetting to take the ACO when travelling (13/50). Fifty-four percent of patients who had an aid to help them take their ACO (pillbox, etc.) proved to be unobservant.

More than half of patients had at least one non-adherence event in the first 3 months of OAC, indicating a need to secure the initiation of these treatments. Compliance must be assessed using appropriate tools. Finally, the institutional score intercepts more outright non-compliance, whereas the GIRERD score would underestimate non-compliance in our cohort.

More than half the patients in our cohort appear to be poorly compliant at an early stage, whatever the assessment score. This assessment of compliance constitutes a feasibility study for the use of our questionnaire in routine clinical monitoring of patients receiving an OAC.