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Background:  In resource-limited setting, HIV infection is often identified among women through voluntary counseling and testing followed by short-course zidovudine (AZT) or single dose nevirapine (NVP) to prevent mother-to-child transmission. In scaling-up antiretroviral therapy (ARV) in Africa, treatment with low-cost, generic dual nucleoside (NRTI) + non-nucleoside reverse transcriptase inhibitor (NNRTI) therapies are recommended. However, there is growing concern about the effect of maternal prophylaxis for prevention of mother-to-child transmission on the activity and response to HAART regimens.

Methods:  Among HIV-positive post-partum women and their spouses, CD4 counts identified 43 women who received ARV  to prevent MTCT (13 NVP and 30 AZT) and 27 men whose wives received NVP (11) or AZT (17). Treatment was initated with generic AZT+lamivudine (3TC) (Duovir) twice daily and NVP (Nevimmune) 200 mg twice daily (CIPLA, Mumbai, India). CD4 counts were evaluated using pan-leukogating, dual platform FACS and HIV-1 RNA quantified by Roche Amplicor (1.5). Virologic and immunologic responses were compared between men and women, by Student’s t-test, and virologic responses analyzed taking into account remote maternal exposure to single-dose NVP or short-course AZT. 

Results:  A total of 70 subjects (43 women and 27 men) completed 16 weeks of therapy. Women were significantly younger than men 31.6 ± 4.5 vs 36.8 ± 5.9 years, respectively, p < 0.001. Mean CD4 counts for women and men were 127.7 ± 66.0 (95% CI 107.3 to 148.0) and 104.1 ± 53.3 (CI 83.0 to 125.2) cells/μL, respectively; and geometric mean virus load, log₁₀ 4.9 copies/mL was similar for women and men. At 16 weeks, mean CD4 counts for women and men increased to 246.3 ± 119.9 (CI 209.4 to 283.3) and 224.1 ± 118.1 (CI 177.4 to 270.9) cells/μL, respectively (p < 0.001) and 62 of 70 (87%) had < 500 copies/mL. Of the 8 with viremia, 3 of 27(11%) were men; 3 of 11 of their wives had received single-dose NVP vs 0 of the 16 whose wives received short-course AZT. This rate was similar to women where 5 of 43 (12%) were viremic; 4 of 30 with previous exposure to short-course AZT and 1 of 13 exposed to single-dose NVP.

Conclusions:  In this early analysis of generic NVP-based treatment for subtype-C HIV-1, previous exposure to single-dose NVP was not more likely than short-course AZT to impair a rapid virologic response to NVP-based generic HAART. Community-based monitoring and counseling, management of toxicities and promotion of adherence will allow evaluation of remote prevention of mother-to-child transmission regimens on the response to generic, NVP-based HAART.     

Keywords: Subtype C; Nevirapine; MTCT and HAART