Which pharmacogenomic variant is most strongly associated with carbamazepine-induced Stevens-Johnson syndrome/toxic epidermal necrolysis in Southeast Asian populations?
- A CYP2C19 poor metabolizer status
- B SCN1A loss-of-function variant
- C HLA-B*15:02 allele ✓
- D HLA-A*31:01 allele
Correct answer: C. HLA-B*15:02 allele
Explanation
The HLA-B*15:02 allele has an extremely strong association with carbamazepine-induced Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) in Han Chinese, Thai, and other Southeast Asian populations — the odds ratio exceeds 1000. The FDA and regulatory agencies mandate HLA-B*15:02 testing before initiating carbamazepine in patients with Asian ancestry. HLA-A*31:01 is associated with carbamazepine hypersensitivity (maculopapular exanthem, DRESS, and SJS/TEN) in European and Japanese populations but is different from B*15:02.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.