Nevirapine concentrations in newborns receiving an extended prophylactic regimen.
BACKGROUND
The optimal neonatal antiretroviral (ARV) regimen for prevention of HIV mother-to-child transmission (MTCT) is unknown for infants born to mothers who receive no ARVs during pregnancy.


METHODS
As part of a protocol comparing the efficacy of 3 neonatal ARV regimens in preventing HIV-1 MTCT in neonates born to mothers who receive no prenatal treatment with ARVs, we devised a 3-dose nevirapine (NVP) regimen with the goal of maintaining the NVP plasma concentration >100 ng/mL (10 times the in vitro median inhibitory concentration of 10 ng/mL) during the first 2 weeks of life. NVP concentrations were measured in 14 newborns participating in a pharmacokinetics substudy during the second week of life and in single samples from 30 more newborns on day 10 to 14.


RESULTS
The median NVP elimination half-life was 30.2 hours (range: 17.8 to 50.3 hours). The NVP concentration remained greater than the target of 100 ng/mL in all samples collected through day 10 of life. By day 14, more than half of the newborns in the pharmacokinetic substudy had NVP levels <100 ng/mL, although only 1 neonate had no detectable NVP.


CONCLUSIONS
Although this regimen failed to meet our 100-ng/mL target, it did maintain detectable NVP concentrations in nearly all newborns through the end of the second week of life and is to be used in the parent efficacy protocol.
Mirochnick
Mark
M
Department of Pediatrics, Boston University School of Medicine, Boston, MA 02118, USA. markm@bu.edu
Nielsen-Saines
Karin
K
Pilotto
Jose Henrique
JH
Pinto
Jorge
J
Jiménez
Eleanor
E
Veloso
Valdilea G
VG
Parsons
Teresa
T
Watts
D Heather
DH
Moye
Jack
J
Mofenson
Lynne M
LM
Camarca
Margaret
M
Bryson
Yvonne
Y
D019380:Anti-HIV Agents / Q000493:pharmacokinetics / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D005260:Female; D015658:HIV Infections / Q000517:prevention & control* / Q000635:transmission; D015497:HIV-1 / Q000187:drug effects; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D019829:Nevirapine / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000821:virology*; D016896:Treatment Outcome; D019562:Viral Load
D019380:Anti-HIV Agents; D019829:Nevirapine