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Published on: February 28, 2019
[HLA-B*5701 and abacavir hypersensitivity reaction]
A Servonnet1, E Leclercq, H Delacour
1Laboratoire de biochimie, hôpital d'instruction des armées Bégin, 69, avenue de Paris, 94163 Saint-Mandé cedex, France. a_servonnet@yahoo.fr
Pathologie-Biologie
|February 27, 2009
Summary
Abacavir hypersensitivity, a severe reaction to HIV drug therapy, is linked to the HLA-B*5701 genetic marker. Genetic screening for HLA-B*5701 is now used to prevent these dangerous reactions in patients.
Area of Science:
- Immunology
- Pharmacogenomics
- HIV Therapeutics
Context:
- Abacavir, a nucleoside analogue, is a crucial component of HIV treatment regimens.
- A significant subset of patients (4-8%) experience severe hypersensitivity reactions upon initiating abacavir therapy.
- The immune system is implicated in the pathogenesis of abacavir hypersensitivity.
Purpose:
- To elucidate the immunological mechanisms underlying abacavir hypersensitivity.
- To investigate the association between abacavir hypersensitivity and specific human leukocyte antigen (HLA) alleles.
- To highlight the clinical utility of HLA-B*5701 screening in preventing abacavir hypersensitivity.
Summary:
- Abacavir hypersensitivity is an immune-mediated reaction potentially triggered by the presentation of abacavir peptides to T-cells via HLA molecules.
- A strong correlation exists between the development of abacavir hypersensitivity and the presence of the HLA-B*5701 allele.
- Prospective screening for the HLA-B*5701 allele has been implemented to mitigate the risk of hypersensitivity reactions.
Impact:
- Implementation of HLA-B*5701 screening significantly reduces the incidence of abacavir hypersensitivity.
- Pharmacogenetic testing improves patient safety in HIV therapy.
- This approach exemplifies personalized medicine in managing drug-induced hypersensitivity.
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