Independent effects of nevirapine prophylaxis and HIV-1 RNA suppression in breast milk on early perinatal HIV-1 transmission.
BACKGROUND
The mechanism of action of single-dose nevirapine on reducing mother-to-child transmission of HIV-1 may involve reduction of maternal HIV-1 or prophylaxis of infants.


METHODS
In a study that randomized pregnant mothers to HIVNET 012 nevirapine versus short-course antenatal zidovudine, we compared breast milk HIV-1 RNA viral shedding and administration of single-dose nevirapine between mothers who transmitted HIV-1 to their infants at 6 weeks postpartum and those who did not.


RESULTS
In multivariate analyses, maximum breast milk HIV-1 RNA levels (hazard ratio [HR] = 2.50, 95% confidence interval [CI]: 1.25 to 4.99; P = 0.01) and nevirapine use (HR = 0.12, 95% CI: 0.02 to 0.97; P = 0.05) were each independently associated with perinatal transmission at 6 weeks postpartum. Mothers who transmitted HIV-1 to their infants had significantly higher HIV-1 RNA levels in their breast milk between the second day and sixth week postpartum. Among mothers with maximum breast milk virus levels less than a median of 3.5 log(10) copies/mL, the administration of nevirapine further decreased HIV-1 transmission risk from 22.2% to 0.0% (P = 0.04).


CONCLUSIONS
Peripartum administration of single-dose nevirapine to mother and infant decreases early perinatal HIV-1 transmission by means of breast milk HIV-1 RNA suppression and, independently, by providing the infant with exposure prophylaxis.
Chung
Michael H
MH
Department of Medicine, University of Washington, Seattle, WA 98104, USA. mhchung@u.washington.edu
Kiarie
James N
JN
Richardson
Barbra A
BA
Lehman
Dara A
DA
Overbaugh
Julie
J
Njiri
Francis
F
John-Stewart
Grace C
GC
D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D004279:DNA, Viral / Q000187:drug effects; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy* / Q000517:prevention & control / Q000635:transmission; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D007630:Kenya; D008895:Milk, Human / Q000821:virology*; D019829:Nevirapine / Q000627:therapeutic use*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy* / Q000821:virology; D012367:RNA, Viral / Q000032:analysis / Q000097:blood / Q000187:drug effects*; D012725:Sexual Behavior; D019562:Viral Load
D019380:Anti-HIV Agents; D004279:DNA, Viral; D012367:RNA, Viral; D019829:Nevirapine