Thior 2006.

Methods	Randomized controlled trial
Participants	1200 HIV‐infected women were randomized.  Primary efficacy (HIV infection by age 7 months and HIV‐free survival by age 18 months) and safety (occurrence of infant adverse events by 7 months of age) end points were evaluated in 1179 infants. Median maternal age = 26.78 years; 55% had water tap in the yard, 37% used communal standpipe; 74% cited private latrine/house as the most used sanitation facility; 24% had electricity in the home; the maternal baseline CD4 count was 366 cells/mm3 and the median maternal baseline plasma viral load was 4.35 log10 copies/mL
Interventions	Mothers were instructed to initiate and complete weaning when the infant was between five and six months of age.  Infants were randomized to 6 months of breastfeeding plus prophylactic infant zidovudine (breastfed plus 6 months of zidovudine) or formula feeding plus 1 month of infant zidovudine (formula fed). Infants received zidovudine syrup 4 mg/kg/12 hours from birth until 1 month of age in all infants, and discontinued at 1 month in the formula‐fed group.  For the breastfed plus zidovudine group, infant zidovudine prophylaxis continued from 1 to 2 months of age at 4 mg/kg/8 hours, and from 2 to 6 months of age (while still breastfeeding) at 6 mg/kg/8 hours. (All mothers received zidovudine 300 mg orally twice daily from 34 weeks gestation and during labor.).  Mothers and infants were randomized to receive single‐dose nevirapine or placebo.
Outcomes	Morbidity: The rates of grade 3 or higher signs or symptoms (17.6% vs. 13.1%; P = 0.03) and of hospitalization (20.3% vs. 15.6%, P = 0.04) by 7 months were significantly higher among infants in the formula‐fed group than in the breastfed plus zidovudine group.   Mortality: Cumulative mortality or HIV infection rates at 18 months were 80 infants (13.9%, formula fed) vs. 86 infants (15.1% breastfed plus zidovudine) (P = 0.60).  Cumulative infant mortality at 7 months was significantly higher for the formula‐fed group than for the breastfed plus zidovudine group (9.3% vs. 4.9%; p = 0.003), but this difference diminished beyond month 7 such that the time‐to‐mortality distributions through age 18 months were not significantly different (P = 0.21).  Therefore, breastfeeding with zidovudine prophylaxis for six months was associated with a lower mortality rate at 7 months, but both strategies had comparable HIV‐free survival at 18 months.
Notes	Adverse effects: The rate of grade 3 or higher laboratory abnormality associated with zidovudine toxicity was significantly higher in the breastfed plus zidovudine group than in the formula‐fed group (24.7% vs. 14.8%) (P < 0.001).
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk	Centralized randomization to both part 1 and part 2 groups occurred at study enrolment (34 weeks gestation), using permuted blocks of size 8 within each site.
Allocation concealment?	Unclear risk	Probably done, but exactly how is unclear.
Blinding? All outcomes	High risk	This study was not blinded.
Incomplete outcome data addressed? All outcomes	High risk	Not addressed.
Free of selective reporting?	Unclear risk	Possibly some post‐randomization selection bias.
Free of other bias?	Low risk	No problems apparent.