Purpose
To evaluate the impact that a pharmacistmanaged oral anticancer clinic has on patient adherence to oral anticancer therapy in regard to medication adherence and adherence to lab monitoring.
Background
Oral anticancer therapy is typically preconceived to be safer than intravenous. However, these medications have a narrow therapeutic window and significant toxicities, requiring close monitoring to ensure patient safety. Previous studies have shown that pharmacist-led oral anticancer clinics have improved adherence and decreased toxicity.
Methods
A retrospective chart review was completed for patients prescribed abiraterone, enzalutamide, or ibrutinib. The primary outcome assessed medication adherence by comparing the medication possession ratio (MPR) before (phase 1) and after (phase 2) the initiation of the pharmacist-led oral anticancer therapy clinic. The secondary outcome assessed lab monitoring adherence by patients and providers in phase 1 vs. phase 2. This study also examined descriptive outcomes in phase 2.
Data Analysis
Independent sample t tests were used to analyze primary and secondary endpoints. For descriptive endpoints, standard deviations and range of scores were assessed for continuous variables.
Results
A statistically significant increase in the mean MPR ratio was shown between phase 1 vs phase 2 (0.98 vs 1.05; P = .027). For patient adherence to lab monitoring, there was a statistically significant improvement for patients on abiraterone (21.9% vs. 67%; P < .001) and enzalutamide (35.7% vs 90.5%; P = .006). There was a decline in lab monitoring adherence for patient on ibrutinib but this effect was not statistically significant (56.2% vs. 51%; P = .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.
Conclusions/Implications
A pharmacist-led oral anticancer clinic can improve MPR ratios and patient adherence to oral anticancer regimens. Patient and provider lab monitoring adherence was improved for abiraterone and enzalutamide. Improvement in patient/ provider lab monitoring adherence for ibrutinib was not shown, possibly due to the impact of the COVID-19 pandemic, small sample size, and retrospective nature of this study. The results of this study supports that overall, a pharmacist-led oral anticancer clinic can significantly improve patient outcomes, which aligns with previous smaller studies.