HLA-B and toxic epidermal necrolysis: Furthermore, considering the 19 HLA alleles associated with adverse events to the therapy with the highest level of evidence, mention should be made of HLA-B*58:01, which has been shown to have a strong effect on the development of severe cutaneous adverse reactions (SCARs), including Stevens—Johnson syndrome and toxic epidermal necrolysis after treatment with allopurinol, the common treatment for hyperuricemia and gout.