Delayed thrombocytopenia following administration of abciximab: Pharmacovigilance survey and literature review

Background. Abciximab (ABX) is used for acute coronary syndrome and unstable angina. Thrombocytopenia is a frequent adverse effect described as occurring in the first 24 hours. The aim of this study was to evaluate, in a context of pharmacovigilance survey, the occurrence of delayed thrombocytopenia following ABX infusion in pharmacovigilance database reports and in the literature. Methods. Individual case safety reports (ICSRs) of delayed thrombocytopenia between 3 and 30 days - with ABX presented as a single suspect were selected in VigiBase, the WHO global database of ICSRs. The French cases were then extracted from the French national pharmacovigilance database. In addition, a literature review of published cases was performed using PubMed. Results. Among the 84 ICSRs selected from VigiBasec', 43 were also reported in the FPVD. Mean age was 60.1 +12.3 years with a majority of male patients (77.4%). The average time to onset (TTO) was 8.9 5.2 days. Thrombocytopenia regressed in 5.1 2.7 days. Haemorrhagic complications were reported in 15% of ICSRs. In the French cases, the median nadir of platelet count was 28 \ 109/L (range 1-110) with a majority of grade 4 thrombocytopenia (39.5%). The literature review identified 42 cases and provided additional information on administered therapies, which include platelet units, corticosteroids, and IV immunoglobulins. GPIlb/111a-ABX complex antibodies were described in 26 published cases. Conclusion. Delayed thrombocytopenia, probably due to immune reaction, is a possible life threatening adverse effect of ABX with a mean TTO of 9 days, supporting the recommendation of a platelet count monitoring during at least two weeks. This recommendation was added to the abcximab SmPC in 2019. (C) 2021 Societe francaise de pharmacologie et de therapeutique. Published by Elsevier Masson SAS. All rights reserved.