HLA-B* 5701 detection

The HLA-B5701 detection test identifies individuals who carry the HLA-B5701 allele, a genetic variant strongly associated with an increased risk of abacavir hypersensitivity reaction (AHR). This test is primarily used in HIV care to guide safe prescribing of abacavir-containing antiretroviral therapy, but it may also be relevant in other clinical contexts where abacavir exposure is considered. The test is performed using a simple blood sample, with analysis typically carried out by polymerase chain reaction (PCR) or sequence-specific oligonucleotide probing (SSOP) to detect the presence of the allele.

Who is this test for?
- Individuals living with HIV who are being considered for abacavir-containing treatment regimens.
- Patients with a history of suspected abacavir hypersensitivity where confirmatory genetic testing is needed.
- Anyone for whom abacavir therapy is being contemplated and risk stratification is required.

Biomarkers included
- HLA-B*5701: A specific allele of the human leukocyte antigen (HLA) system. Its presence indicates a significantly elevated risk of developing a hypersensitivity reaction if exposed to abacavir. A negative result makes abacavir hypersensitivity very unlikely.

Why it matters
Identifying HLA-B*5701 carriers before initiating abacavir can prevent potentially life-threatening hypersensitivity reactions. This test empowers clinicians to personalise treatment, avoid unnecessary exposure, and improve patient safety in HIV management and other relevant therapeutic areas.