Postmarketing Safety Concerns With Caplacizumab: A Real-World Pharmacovigilance Study Based on the FDA Adverse Event...

To analyze data from the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) database to characterize the adverse effects of caplacizumab, including associated adverse events (AEs) and safety signals in real-world clinical practice. and obtain evidence to support the rational use of this drug in the treatment of thrombotic thrombocytopenic purpura (TTP).

Postmarketing AE reports associated with caplacizumab were retrieved from the FAERS database. Safety signals were identified using four disproportionality analysis methods: the reporting odds ratio, proportional reporting ratio, Bayesian Confidence Propagation Neural Network (BCPNN), and multi-item gamma Poisson shrinker. The Weibull distribution was used to analyze the onset time of AEs, and subgroup analyses were performed according to sex, age group, and reporter type.

In total, 1144 reports involving caplacizumab were analyzed. Most AEs were nonserious. Among the 401 reports with documented onset times, 162 (40.4%) described AEs occurring within 7 days of administration. Common bleeding-related events (e.g., epistaxis, gingival bleeding, gastrointestinal hemorrhage, heavy menstrual bleeding, and vaginal hemorrhage) were consistent with product labeling. Decreases in platelet count and in disintegrin and metalloproteinase with thrombospondin type 1 motif 13 (ADAMTS13) activity were interpreted as manifestations of the underlying disease (acquired TTP) rather than drug-induced AEs. Newly identified safety signals included contusion, injection site pain, injection site bruising, injection site erythema, injection site haemorrhage, pruritus and rash.

These findings underscore the importance of pharmacovigilance and postmarketing surveillance for caplacizumab. Clinicians should closely monitor bleeding events and injection site reactions during treatment. To ensure the safe use of caplacizumab, the mechanisms underlying these potential signals should be elucidated, and targeted monitoring strategies should be developed.