HLA-Cw*04 allele associated with nevirapine-induced rash in HIV-infected Thai patients

BACKGROUND A high incidence of rash has been reported in HIV-1 patients who received the anti-retroviral drug nevirapine. In addition, several studies have suggested that polymorphisms of human leukocyte antigen (HLA) genes may play important roles in nevirapine-induced rash. The aim of the present study was to evaluate the effects of different HLA-C alleles on rash associated with nevirapine in patients who started highly active anti-retroviral therapy (HAART) containing nevirapine in Thailand. RESULTS A case-control study was carried out involving HIV-1 patients under treatment at Bamrasnaradura Infectious Diseases Institute, Nonthaburi, Thailand between March 2007 and March 2008. The study included all HIV/AIDS patients being treated with nevirapine-containing regimens. The study population comprised 287 HIV/AIDS patients of whom 248 were nevirapine-tolerant and 39 developed rash after nevirapine treatment. From the nevirapine-tolerant patients, 60 were selected as the control group on the basis of age, sex, and therapy history matched for nevirapine-induced rash cases. We observed significantly more HLA-Cw*04 alleles in nevirapine-induced rash cases than in nevirapine-tolerant group, with frequencies of 20.51% and 7.50%, respectively (P = 0.009). There were no significant differences between the rash and tolerant groups for other HLA-C alleles except for HLA-Cw*03 (P = 0.015). CONCLUSION This study suggests that HLA-Cw*04 is associated with rash in nevirapine treated Thais. Future screening of patients' HLA may reduce the number of nevirapine-induced rash cases, and patients with alleles associated with nevirapine-induced rash should be started on anti-retroviral therapy without nevirapine.