Highly Active Antiretroviral Therapy Started during Pregnancy or Postpartum Suppresses HIV-1 RNA, but Not DNA, in Breastmilk

Roger L. Shapiro,1,4 Thumbi Ndung'u,1 Shahin Lockman,1,3 Laura M. Smeaton,2 Ibou Thior,1 Carolyn Wester,1 Lisa Stevens,1 Gaseene Sebetso,5 Simani Gaseitsiwe,5 Trevor Peter,1 and Max Essex1
1Department of Immunology and Infectious Diseases and 2Center for Biostatistics in AIDS Research, Harvard School of Public Health, 3Infectious Disease Unit, Brigham and Women's Hospital, and 4Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, Massachusetts; 5Botswana Harvard School of Public Health AIDS Initiative Partnership for HIV Research and Education, Bontleng, Gaborone, Botswana
(See the editorial commentary by Bulterys et al. and the article by Shapiro et al)

Background. The ability of highly active antiretroviral therapy (HAART) to reduce human immunodeficiency virus type 1 (HIV-1) RNA and DNA in breast milk has not been described.
Methods. We compared breast-milk HIV-1 RNA and DNA loads of women in Botswana who received HAART (nevirapine, lamivudine, and zidovudine) and women who did not receive HAART.
Results. Women in the HAART group received treatment for a median of 98 days (range, 67 222 days) at the time of breast-milk sampling; 23 (88%) of 26 had whole breast-milk HIV-1 RNA loads <50 copies/mL, compared with 9 (36%) of 25 women who did not receive HAART (P = .0001). This finding remained significant in a multivariate logistic-regression model (P = .0006). The whole-milk HIV-1 DNA load was unaffected by HAART. Of women who received HAART, 13 (50%) of 26 had HIV-1 DNA loads <10 copies/106 cells, compared with 15 (65%) of 23 who did not receive HAART (P = .39).
Conclusions. HAART suppressed cell-free HIV-1 RNA in breast milk and may therefore reduce mother-to-child transmission (MTCT) of HIV-1 via breast-feeding. However, HAART initiated during pregnancy or early after delivery had no apparent effect on cell-associated HIV-1 DNA loads in breast milk. Clinical trials to determine MTCT among breast-feeding women receiving HAART are needed.

Received 14 February 2005; accepted 18 April 2005; electronically published 27 July 2005.
Presented in part: 12th Conference on Retroviruses and Opportunistic Infections, Boston, 22 25 February 2005 (poster 793b).
Potential conflicts of interest: none reported.
Financial support: National Institutes of Childhood Health Development (grants R01-HD37793 and K23-HD01330).
Reprints or correspondence: Dr. Roger L. Shapiro, Div. of Infectious Diseases, Beth Israel Deaconess Medical Center, 110 Francis St, Suite GB, Boston, MA 02215 (rshapiro@bidmc.harvard.edu).