HLA-B and Scarring: However, some researchers suggested a future recalculation of the cost-effectiveness of pre-treatment HLA-B*58:01 screening based on updated local data on HLA-B* 58:01 allele frequencies for multiple ethnic groups, effect size for association of this allele with allopurinol-induced SCAR and incidence rate of allopurinol-induced SCAR in Malaysia [10].