Identifying patients with HLA-related ADRs
To determine the number of patients who experienced HLA-related ADRs due to the seven drugs included in this study, the prescription data of participants, HLA allele information, diagnostic codes of type B ADRs such as “toxic maculopapular eruption,” “acute generalized exanthematous pustulosis (AGEP),” “SJS,” “TEN,” “DRESS syndrome,” and “drug eruption” were reviewed in SUPREME®. Because it may be inaccurate to determine patients’ drug allergies or idiosyncratic type B ADRs based on the diagnosis code alone, we obtained the list of patients who had type B ADRs from the Individual Case Safety Reports database (ICSRs) (Supplementary Table 2) of the Drug Safety Center at SNUH since January 1, 2009. The final list of patients who experienced HLA-related ADRs was obtained by combining the data from the SUPREME® data warehouse and ICSRs.