Clinical characteristics of adverse events associated with therapeutic monoclonal antibodies in Korea

Purpose: The use of monoclonal antibodies (mAbs) is increasing in various clinical fields. Although mAb safety must be demonstrated prior to approval, targeted pharmacovigilance is essential for the recognition and assessment of adverse reactions. The purpose of this study was to identify the major clinical features of adverse reactions to mAbs in Korea. Methods: Spontaneous reports of adverse reactions attributed to 18 mAbs from January 2005 to December 2014 were extracted from the Korea Adverse Event Reporting System. We analyzed these reports for information relating to patient characteristics and the types of adverse reactions. Results: In total, 11 492 adverse reactions were reported in 7569 patients. Almost 19% of total study population showed suspected hypersensitivity reactions. Leukocyte abnormalities were reported frequently (10.0%), as well as infections (9.5%), drug eruptions (7.5%), and pruritus (5.0%). Furthermore, 3716 of the adverse reactions in 2538 patients were classified as serious; these included severe infections (18.2%), neutropenia (12.1%), visual dysfunctions (6.6%), and anaphylaxis (4.8%). The mAbs with the highest number of adverse reaction reports were rituximab (27.6%), adalimumab (17.5%), cetuximab (11.9%), and infliximab (10.7%). Conclusions: Hypersensitivity reactions were observed more frequently than expected, although no previously unrecognized reactions were observed. Adverse reactions occurred more frequently in children and in elderly patients. Close monitoring of adverse reactions to therapeutic mAbs is therefore warranted because these can potentially cause serious medical conditions or death.