HLA-B and drug allergy: According to a recent report from South Korea, where the frequency of HLA-B*5701 is almost 0% as well, although “clinical” hypersensitivity was observed in 5% (7/150) of the subjects, none of them could be confirmed by skin patch test, suggesting that “true” hypersensitivity was rare among Korean patients.31 Similarly, because the present survey aimed to widely collect safety information, false cases, such as simple “allergic reaction” or “drug allergy,” might have been included.