Quantity and economic value of unused oral anti-cancer and biological disease-modifying anti-rheumatic drugs among outpatient pharmacy patients who discontinue therapy

Abstract

BACKGROUND: Patients sometimes discontinue the use of expensive oral anti-cancer drug (OACD) or biological disease-modifying anti-rheumatic drug (bDMARD) therapies early, leading to medication waste if the patient has not used all dispensed medication. OBJECTIVE: To determine the proportion of patients who have unused OACDs or bDMARDs after therapy discontinuation, and the quantity and economic value of these unused medications. Furthermore, patients' reasons for therapy discontinuation and their disposal method for unused medications were determined. METHODS: In a retrospective follow-up study using a Dutch outpatient pharmacy database, patients (≥18 years) who did not refill an OACD or bDMARD prescription, dispensed between November 2015 and February 2016, within two weeks of the prescription end date were contacted by phone and asked about their unused medication and reasons thereof. The economic value was calculated using Dutch medication prices. Data were descriptively analyzed in STATA13. RESULTS: The database included 1173 patients, of whom 159 likely had discontinued therapy and were contacted. Of these, 88 patients were excluded (39 refilled, 47 missing, and 2 other). Of the 71 patients who had discontinued therapy, 39 (54.9%) had unused medications, comprising 22 OACD users (mean age 63.0 (SD ± 15.9) years, 50.0% female) and 17 bDMARD users (mean age 50.7 (SD ± 13.5) years, 47.1% female). A total of 59 packages were unused, with a total value of €60,341. Unused OACD packages and bDMARD packages had median values of €179 (IQR €24-2487) and €992 (IQR €681-1093), respectively. Patients primarily discontinued therapy due to adverse or insufficient effects. CONCLUSIONS: This study illustrates that more than half of patients discontinuing OACD or bDMARD therapies have unused medication. This emphasizes the need for waste-reducing interventions.