Vertical Transmission and Antiretroviral Resistance
Friday, 1:30 - 3:30 pm
Background: The HIVNET 012 trial in
Methods: Subjects included 67 women with subtype C
Results: The rate of NVP resistance (detection of any NVP-resistance mutation) was higher in women with subtype C (45 of 67 = 67%) than in women with subtype A (28 of 147 = 19%, p < 0.001) or D (35 of 98 = 36%, p < 0.001). The portion of women with 2 or more NVP resistance mutations was also higher for subtype C (29 of 67 = 43%) than for subtype A (12 of 147 = 8%, p < 0.001) or D (16 of 98 = 16%, p < 0.001). The most common NVP resistance mutations detected in all 3 subtypes were K103N and Y181C. The rate of detection of both mutations was higher in women with subtype C than subtypes A or D (p < 0.0001). In a multivariate model, subtype (C vs A OR = 8.38, 95% CI 4.19 to 16.76; C vs D OR = 3.27, 95% CI 1.63 to 6.59) and delivery viral load (OR = 2.23, 95% CI 1.53 to 3.25) were independent predictors of NVP resistance, but age, parity, and NVP dosing time relative to delivery were not. There were no significant differences in age, parity, NVP dosing time, or delivery viral load among women with subtypes A, C, and D.
Conclusions: HIV-1 subtype influences selection of HIV-1 variants with NVP-resistance mutations after single dose NVP exposure. The rate of NVP resistance 6 to 8 weeks after single dose NVP administration was significantly higher in subtype C than subtypes A or D.
Keywords: nevirapine; subtype; resistance