Castellsague J, Calingaert B, Poblador-Plou B, Giner-Soriano M, Linder M, Scholle O, Varas-Lorenzo C, Arana A, Bui C, Prados-Torres A, Gonzalez-Rubio F, Roso-Llorach A, Citarella A, Garbe E, Blenk T, Perez-Gutthann S. Characterization of new users of cilostazol in the United Kingdom, Spain, Sweden, and Germany. Poster presented at the 32nd ICPE International Conference on Pharmacoepidemiology & Therapeutic Risk Management; August 26, 2016. Dublin, Ireland. [abstract] Pharmacoepidemiol Drug Saf. 2016 Aug; 25(Suppl 3):203-4.

BACKGROUND: Cilostazol is indicated in Europe to improve walking distances in patients with intermittent claudication. The European Medicines Agency evaluated the benefit/risk of cilostazol and recommended labeling changes, including addition of unstable angina, recent myocardial infarction, or recent coronary intervention as new contraindications.

OBJECTIVES: To describe the characteristics of new users of cilostazol in Europe to support evaluation of its benefit/risk as used in regular clinical practice before the implementation of new contraindications.

METHODS: New users of cilostazol were identified in five automated health databases—United Kingdom (THIN), Spain (IACSEpiChron and SIDIAP), Sweden (National Registers), and Germany (GePaRD)— between 2002 and 2013. New users were characterized according to the prevalence of cardiovascular disease and other comorbidity, concurrent use of interacting medications, new contraindications, duration of use, and potential offlabel prescribing.

RESULTS: We identified 22,593 new users of cilostazol. Characteristics of users varied across databases. Median age in years ranged from 68.0 (SIDIAP) to 73.7 (Sweden). Between 74.5% (IACS) and 95.7% (GePaRD) of users had cardiovascular disease other than peripheral arterial disease, 78.8% (GePaRD) to 91.6% (THIN) were treated with interacting medications, and 2.7% (Sweden) to 22.3% (THIN) were treated with potent CYP3A4 or CYP2C19 inhibitors. Prevalence of new cardiovascular contraindications ranged from 1.5% (THIN) to 11.6% (GePaRD), and concurrent use of two or more antiplatelet drugs ranged from 6.3% (SIDIAP) to 13.5% (IACS). Between 39.4% (Sweden) and 52.9% (THIN) of users discontinued cilostazol in the first 3 months. Between 41.0% (SIDIAP) and 93.4% (THIN) of users were considered to have received cilostazol according to the labelling.

CONCLUSIONS: This collaborative European study showed that most cilostazol users were elderly patients with a high prevalence of comorbidity, particularly of cardiovascular diseases, high concurrent use of interacting drugs, and high discontinuation rates in the first 3 months of treatment.