The impact of a pharmacist-led oral anticancer clinic on medication adherence and laboratory monitoring

Purpose To evaluate the impact that a pharmacist-managed oral anticancer clinic has on patient adherence to oral anticancer therapy in regard to medication adherence and adherence to lab monitoring. Methods A retrospective chart review was completed for patients prescribed abiraterone, enzalutamide, or ibrutinib within the study time period. The primary outcome was assessing medication adherence by comparing the medication possession ratio (MPR) before (Phase 1) and after (Phase 2) initiation of the pharmacist-led oral anticancer therapy clinic. The secondary outcome was assessing lab monitoring adherence by patients and providers in Phase 1 and Phase 2. This will be done by assessing whether labs were ordered at the appropriate time frame by oncology providers, as well as whether or not the patient came and got these labs drawn. This study will also examine outcomes related to the pharmacist-led oral anticancer therapy clinic (phase 2) for descriptive purposes. Results A total of 189 charts were analyzed with 134 excluded and 55 included (25 patients in phase 1 and 30 patients in phase 2). Independent sample t-test analyses revealed a statistically significant increase (t(30.57) = -1.99; p = 0.027) in the MPR ratio between phase 1 (mean = 0.98, SD = 0.13) compared to phase 2 (mean = 1.04, SD = 0.08). For patient adherence to lab monitoring, there was a statistically significant improvement between phase 1 and phase 2 for patients on abiraterone (21.9% vs 67%; t(25) = -5.73; p < 0.001) and enzalutamide (35.7% vs. 90.5%; t(8) = -3.26; p = 0.006). However, for patients on ibrutinib, there was a slight decline in lab monitoring adherence between phase 1 and phase 2 but this effect was not statistically significant (56.2% vs. 51%; t(17) = 0.58; p = 0.283). Similar results were shown for provider adherence to lab monitoring. Descriptive outcomes showed that the pharmacist had, on average, 6.7 encounters per patient with the majority being phone and face-to-face appointments. Conclusions Data from this study demonstrated that a pharmacist-led oral anticancer clinic can improve MPR ratios and patient adherence to oral anticancer medication regimens. In addition, patient and provider lab monitoring adherence was improved for abiraterone and enzalutamide. Improvement in patient and provider lab monitoring adherence for ibrutinib was not shown, possibly due to the impact of the COVID-19 pandemic, relatively small sample size, and retrospective nature of this study. The results of this study support that overall, a pharmacist-led oral anticancer clinic can significantly improve patient outcomes, which aligns with previous smaller studies that have shown similar benefits.