Ticlopidine Safety Profile: A Case/Non-Case Study on the Basis of the Spontaneous ADRs Reporting in Italy

Introducton: Ticlopidine is an antiplatelet agent available from several decades. Its most important adverse drug reactions (ADRs) involve haematological system. Our aim was to evaluate the safety profile of ticlopidine in the real life, on the basis of spontaneous ADR reporting. Materials and Methods: Spontaneous reports from 8 Italian Regions collected from 1990 to March 2007 were analysed. According to WHO Adverse Reaction Terminology for causality assessment only “certain”, “probable” or “possible” ADRs were included. Association between drugs and any ADR was assessed by using the case/non-case methodoloy. Reporting odds ratio (ROR) was computed as a measure of disproportionality. Results: Overall, 478 reports concerning ticlopidine were analysed. The system organ classes with significant disproportionality for ticlopidine included White Cell Disorders (ROR=22.43, 95% CI 18.54–27.12), Red Cell Disorders (8.22; 6.03-11.18), Liver And Biliary System (6.67; 5.35–8.32), Platelet, Bleeding & Clotting (6.59; 5.16-8.40). Fifteen percent of the ADRs occurred beyond the first three months of ticlopidine therapy. In 386 reports (80.7%), ticlopidine was the only suspected drug. Conclusion: Safety profile of ticlopidine can be considered well-established in terms of ADRs type but their frequency and severity continue to be higher in its current use. Since this drug is still widely used in Italy, both healthcare providers and patients should be aware of its ADRs. More specifically, patients should be regularly monitored during the whole period of use and not only in the first months of treatment.