The HLA-B*57:01 allele has been associated with hypersensitivity to abacavir, a highly effective
nucleoside analog reverse-transcriptase inhibitor used to treat HIV infection and AIDS. Per the Clinical
Pharmacogenomics Implementation Consortium (CPIC) dosing guidelines for abacavir and HLA-B, individuals
who are positive for the HLA-B*57:01 allele are at an increased risk for abacavir hypersensitivity and it
is not recommended for use in treating these individuals.