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Association between CYP2B6 polymorphisms and Nevirapine-induced SJS/TEN: a pharmacogenetics study
Cinzia Ciccacci1, Davide Di Fusco, Maria C Marazzi
1Department of Biomedicine and Prevention, Genetics Section, School of Medicine, University of Rome "Tor Vergata", 00133, Rome, Italy.
European Journal of Clinical Pharmacology
|June 19, 2013
Summary
Genetic variations in the CYP2B6 gene are linked to severe skin reactions from nevirapine (NVP), a crucial HIV drug. Specific CYP2B6 gene variants increase the risk of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN).
Area of Science:
- Pharmacogenetics
- Immunology
- Drug Metabolism
Background:
- Nevirapine (NVP) is a key non-nucleoside reverse transcriptase inhibitor for HIV-1 treatment.
- A subset of patients develop severe cutaneous adverse events (SCAEs) like Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) upon NVP administration.
- The genetic basis for NVP-induced SJS/TEN susceptibility remains incompletely understood.
Purpose of the Study:
- To investigate the potential role of genetic variations in drug-metabolizing enzymes and transporter genes in NVP-induced SJS/TEN.
- To identify specific genetic markers associated with increased risk of severe cutaneous adverse events.
Main Methods:
- A case-control study was conducted with 27 patients experiencing NVP-induced SJS/TEN and 78 controls from Mozambique.
- Genotyping was performed for variants in transporter genes (ABCB1, ABCC10) and cytochrome genes (CYP2B6, CYP3A4, CYP3A5).
- Case-control and genotype-phenotype analyses were employed to assess associations.
Main Results:
- Specific single nucleotide polymorphisms (SNPs) in the CYP2B6 gene, namely G516T and T983C, were significantly associated with SJS/TEN susceptibility.
- The 983C allele demonstrated a strong association with an elevated risk of developing SJS/TEN (OR=4.2, P=0.0047).
- The GT haplotype (wildtype for both SNPs) exhibited a protective effect against SJS/TEN (OR=0.33, P=0.0016).
Conclusions:
- This study provides the first evidence linking genetic variability in a metabolizing enzyme, CYP2B6, to susceptibility to nevirapine-induced SJS/TEN.
- Genetic polymorphisms in CYP2B6 represent a significant risk factor for severe cutaneous adverse events in patients treated with nevirapine.
- These findings have implications for personalized medicine approaches in HIV treatment.
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