1. ARV drug concentrations in breastmilk, HIV viral load, and HIV transmission to the infant
Nicole L Davis, Amanda Corbett, Joshua Kaullen,
Julie AE Nelson, Charles S Chasela, Dorothy Sichali,
Michael G Hudgens, William C Miller, Denise J Jamieson,
and Athena P Kourtis on behalf of the BAN Study Team.
No conflicts of interest to declare.
Abstract MOPDC0103
9th IAS Conference on HIV Science
July 24, 2017
National Center for Chronic Disease Prevention and Health Promotion
Division of Reproductive Health

2. METHODS
Cohort study - data from the Breastfeeding, Antiretrovirals and Nutrition study (Lilongwe, Malawi; ) Included all mothers randomized to 28 weeks of postpartum maternal ARVs or daily infant nevirapine who transmitted HIV to their infants between 2-28 weeks (n=27) and 15% of mothers who did not transmit (n=227) Plasma and breastmilk drug concentrations dichotomized using the median effective concentration (EC50) Plasma and breastmilk viral load dichotomized as detectable (plasma: >40 copies/ml, breastmilk: >56 copies/ml) or not

3. Examine correlation between plasma and breastmilk ARV drug concentrations using Spearman correlation coefficients
All ARV compounds exhibited correlations between plasma and breastmilk concentrations (rho: , p-value <0.0001).

4. Association between maternal drug concentrations, by compartment, and detectable maternal plasma and breastmilk viral load, using mixed effects models
Plasma viral load
Breastmilk viral load
Odds Ratio
(95% CI)
Plasma drug concentrations
>EC50 vs ≤EC50
0.69
(0.49,
0.98)
0.23
(0.15,
0.37)
Breastmilk drug concentrations
0.65
(0.47,
0.89)
0.44
(0.31,
0.62)
Association between drug concentrations, by compartment, and breastmilk HIV transmission between 2-28 weeks, using Cox models
Hazard Ratio
(95% CI)
Plasma drug concentrations
>EC50 vs ≤EC50
0.40
(0.18,
0.93)
Breastmilk drug concentrations
0.31
(0.08,
1.17)
Having plasma drug concentrations >EC50 associated with lower odds of having detectable HIV RNA in both plasma and breastmilk, and reduced rate of breastmilk HIV transmission 2-28 weeks.
Having breastmilk drug concentrations >EC50 associated with lower odds of having detectable HIV RNA in both plasma and breastmilk.

5. We are grateful to the BAN Study Team at the University of North Carolina Chapel Hill, the Centers for Disease Control and Prevention, Atlanta, and the UNC Project team in Lilongwe. Most especially, we are grateful to all the women and infants that agreed to participate in the BAN study CONTACT FOR MORE INFORMATION Nicole L. Davis
The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
National Center for Chronic Disease Prevention and Health Promotion
Division of Reproductive Health