Determinants of nevirapine hypersensitivity and its effect on the association between hepatitis C status and mortality in antiretroviral drug-naive HIV-positive patients.

OBJECTIVE: To assess risks factors and outcomes associated with nevirapine hypersensitivity reactions, and to determine the effect of hypersensitivity as a modifier of the association between hepatitis C virus (HCV) infection and mortality among antiretroviral drug-naive patients. METHODS: The primary endpoint was hypersensitivity reactions in a population-based cohort of antiretroviral therapy-naive HIV-individuals, 18 years or older in British Columbia, Canada, who started triple antiretroviral therapy with nevirapine between May 1997 and June 2003. Univariate and multivariate analyses were performed to identify predictors of nonaccidental mortality in the subgroup of patients with known HCV serostatus. RESULTS: A total of 66 (9.6%) of 685 patients met the definition for hypersensitivity reactions. In the univariate logistic regression analysis, no variables were identified as risk factors. In multivariate survival analyses conducted to identify characteristics associated with nonaccidental mortality, patients with both HCV coinfection and hypersensitivity reactions had a higher risk of death (hazard ratio, 7.12; 95% confidence interval, 2.73-18.53; P < 0.001) compared with those who did not have HCV coinfection or hypersensitivity reaction. CONCLUSION: Results of this study suggest that the hypersensitivity reaction behaves as an effect modifier of the association between HCV infection and mortality in this cohort of antiretroviral drug-naive HIV-positive patients. These results support the current recommendation against the use of nevirapine in HIV/HCV-coinfected patients.