A
minority of patients taking nevirapine will develop a hypersensitivity reaction
soon after starting the drug, characterized by symptoms including skin rash and
elevated liver enzymes. Incidence rates range from approximately 15% for a mild-to-moderate
rash to about 5% for serious liver toxicity. The risk is higher among women with
a CD4 cell count above 250 cells/mm3
and men with more than 400 cells/mm3. People with pre-existing liver disease,
including hepatitis B or C,
are also at higher risk for nevirapine-associated liver toxicity.
In the
present study, researchers assessed risks factors for and outcomes associated
with nevirapine hypersensitivity reactions, and attempted to determine whether
hypersensitivity acts as a modifier of the association between hepatitis
C virus (HCV) infection and mortality.
The
study population was a cohort of antiretroviral treatment-naive HIV positive adults
in British Columbia who started a three-drug
antiretroviral regimen containing nevirapine
between May 1997 and June 2003. Univariate and multivariate analyses were performed
to identify predictors of non-accidental death in the subgroup of patients with
known HCV serostatus.
Results
•
66
of 685 patients (9.6%) met the definition for hypersensitivity reactions.
•
In
a univariate logistic regression analysis, no variables were identified as risk
factors for hypersensitivity.
•
In a multivariate
survival analyses of characteristics associated with non-accidental death, HIV-HCV
coinfected patients with hypersensitivity reactions had about a 7-fold higher
risk of death compared with HIV positive individuals who did not have HCV coinfection
or hypersensitivity reactions (hazard ratio 7.12; P < 0.001).
Conclusion
"Results
of this study suggest that the [nevirapine] 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," the study
authors concluded. "These results support the current recommendation against
the use of nevirapine in HIV-HCV coinfected patients."
Notably, the
deaths in this study were not directly caused by liver failure or other hypersensitivity
complications, but rather seemed to be due to HIV disease progression after patients
interrupted antiretroviral therapy following a reaction.
09/11/07
Reference
E Phillips, S Gutiérrez, N Jahnke, and others. Determinants of
nevirapine hypersensitivity and its effect on the association between hepatitis
C status and mortality in antiretroviral drug-naive HIV-positive patients. AIDS
21(12): 1561-1568. July 31, 2007.
A
minority of patients taking nevirapine will develop a hypersensitivity reaction
soon after starting the drug, characterized by symptoms including skin rash and
elevated liver enzymes. Incidence rates range from approximately 15% for a mild-to-moderate
rash to about 5% for serious liver toxicity. The risk is higher among women with
a 
