Impact of outpatient pharmacy interventions on management of thyroid patients receiving lenvatinib.

Objectives: Medical oncologists and pharmacists at our institution established an integrated support program aimed at preventing unnecessary treatment interruption or dose reduction during oral targeted therapy with lenvatinib. Here, we evaluated the benefits of this program in managing patients with thyroid cancer receiving lenvatinib.

Methods: We retrospectively evaluated thyroid cancer patients who received lenvatinib between May 2015 and March 2017. This descriptive study collected records in which pharmacists contributed to changing doctors' prescriptions and categorized the interventions.

Results: During the study period, 24 thyroid cancer patients were treated with lenvatinib. Among patients, the incidence of temporary interruption and dose reduction of lenvatinib due to adverse drug reactions was 100% (n = 24) and 83.3% (n = 20), respectively. There were 193 temporary interruptions of lenvatinib due to adverse drug reactions. A total of 501 outpatient pharmacy services were conducted by pharmacists in collaboration with oncologists, of which 125 were interventions (24.9%). In addition, pharmacists conducted 156 telephone follow-up services; 18 (11.5%) of these were to consult an oncologist about a patient's confirmed problems and resulted in the decision to continue observation with no medical intervention while 41 (26.2%) resulted in the oncologist deciding to temporarily interrupt lenvatinib treatment after the report of an adverse drug reaction from the pharmacist.

Conclusion: Pharmacist interventions in collaboration with medical oncologists improved lenvatinib therapy. Interventions for outpatients were conducted not only in outpatient clinics but also by telephone follow-up, clarifying the importance of continuous management for patients at risk of adverse reactions and misuse of oral medicine.