Impact of pharmacist managed oral epidermal growth factor receptor inhibitors

Abstract

Background Pharmacists are an integral part of medication management, with the positive impact of their clinical services in patient outcomes previously studied and reported in literature. The roles and responsibilities of pharmacists continue to expand, including optimizing patient medication and health outcomes related to complex oral anticancer drugs. Objective To evaluate the impact of a pharmacist-managed oral chemotherapy clinic in patients with non-small cell lung cancer (NSCLC) taking oral epidermal growth factor receptor inhibitor (EGFRi) regimens within an integrated healthcare delivery system. Methods This was an observational cohort study using data from Kaiser Permanente Northern and Southern California regions on adult patients who received oncology pharmacist-managed care compared to patients with usual care. Patients were newly initiated with EGFRi therapy to treat NSCLC between 2017 and 2019. The follow-up period was defined as the time from index date (first sold date of EGFRi) to December 2020 or end of membership or death, whichever occurred first. Primary outcome measures included adherence to EGFRi, frequency of imaging during drug exposure, and presence of imaging prior to treatment change. Outcomes were analyzed with Chi-square test for categorical variables, and Student's t-test or Wilcoxon rank-sum test for continuous variables. Results There were 613 patients in the pharmacist-managed group and 714 patients in the usual care group. Overall, the mean age was 68.2 ± 11.3 years, and 65.1% were female. In the pharmacist-managed group, there was a significantly higher mean proportion of days covered (PDC) during the first three months of therapy (0.86 ± 0.24 vs 0.82 ± 0.36, p = 0.01) and a higher percentage of patients who were adherent to EGFRi therapy (with PDC ≥0.80) during the drug exposure period (95.8% vs 92.4%, p = 0.01). The rate of computed tomography (CT) and magnetic resonance imaging (MRI) during drug exposure was higher in the pharmacist-managed group compared to the usual care group (31.8% vs 20.7%, p < 0.01) with a higher number of mean scans completed per patient (1.15 ± 2.42 vs 0.62 ± 1.63, p < 0.01) and per patient-year (2.60 ± 7.27 vs 1.58 ± 5.95, p < 0.01). Overall, 66.2% of patients had a treatment change, with a higher percentage of patients in the pharmacist-managed group who completed a CT or MRI scan prior to treatment change (36.3% vs 26.3%, p < 0.01). Additionally, the median time between the scan and treatment change was shorter for patients with pharmacist-managed care (1.8 vs 4 months, p = 0.04). Conclusion Clinical pharmacy services contributed to improved adherence, higher rates of imaging, and shorter time between imaging and treatment changes in NSCLC patients who were taking EGFRi regimens.