Objectives. To determine the frequencies of HLA-B alleles in Ugandan
patients in the NORA substudy of the DART trial and to compare HLA-B
allele frequencies in those with and without clinically diagnosed
hypersensitivity reaction (HSR).
Methods. DNA-based HLA-B genotyping was used to determine HLA alleles in
247 participants who received abacavir, including all six participants
(‘cases’) with clinically diagnosed abacavir HSR.
Results. The incidence of clinical abacavir HSR in this double-blinded
study was 2.0% (6/300) in the abacavir group. As HLA-B*5701 was absent
throughout the entire cohort, including the six HSR ‘cases’, an
association could not be established between HLA-B*5701 and clinically
diagnosed abacavir HSR. No other HLA-B*57 alleles were present among
the six ‘cases’. HLA-B*5703 was the most frequent HLA-B*57 allele
among the abacavir-tolerant participants.
Conclusion.The rate of clinical HSR was low, which may reflect the
expected 2–3% clinical false-positive rate seen in previous double-blind
randomized studies. The presumption that these cases may be
false-positive abacavir HSR is supported by the fact that no HLA-B*5701
alleles were found in the abacavir group. Implementation of prospective
HLA-B*5701 screening must be based on benefit/risk considerations
within local practice. Clinical risk management remains paramount.
Munderi, P.; Snowden, B.W.; Walker, A.S.; Kityo, C.; Mostellar, M.; Kabuye, G.; Thoofer, N.K.; Ssali, F.; Gilks, C.F.; Hughes, A. Distribution of HLA-B alleles in a Ugandan HIV-infected adult population: NORA pharmacogenetic substudy of DART. Tropical Medicine and International Health (2011) 16 (2) 200-204. [DOI: 10.1111/j.1365-3156.2010.02688.x]
Is HLA-B*5701 associated with clinically diagnosed hypersensitivity to abacavir in Ugandan HIV-infected adults?