Steady-state nevirapine plasma concentrations are influenced by pregnancy.
OBJECTIVE
Optimal plasma concentrations of antiretroviral drugs are required during pregnancy to treat maternal HIV infection and prevent mother-to-child transmission. We investigated the effect of pregnancy on nevirapine (NVP) plasma concentrations.


METHODS
We included all HIV-1-infected women for whom NVP plasma concentrations were available as part of routine patient care at two university hospitals. Plasma NVP concentrations were compared for pregnant (n=45) and non-pregnant (n=152) women. Univariate and multivariate linear regression analyses were used to identify and adjust for other confounding factors associated with NVP plasma concentrations. For pregnant women who had a plasma NVP concentration available both during and outside pregnancy, a paired analysis was performed.


RESULTS
Steady-state NVP plasma concentrations were lower in pregnant women: 5.2 mg/L (interquartile range 3.9-6.8) vs. 5.8 mg/L (4.3-7.7) (P=0.08). After adjusting for confounders, both pregnancy (regression coefficient=-0.90 mg/L, P=0.046) and African descent (regression coefficient=+1.13 mg/L, P=0.005) influenced NVP concentrations significantly. The paired analysis showed mean concentrations of 4.8 mg/L during pregnancy and 5.8 mg/L outside pregnancy (paired t-test, P=0.073).


CONCLUSIONS
Pregnancy has a moderate but significant lowering effect on NVP plasma concentrations. Being of African descent compensates for the lowering effect of pregnancy on NVP concentrations.
Nellen
J F J B
JF
Department of Internal Medicine, Division of Infectious Diseases, Tropical Medicine and AIDS, Academic Medical Centre, University of Amsterdam, The Netherlands. f.j.nellen@amc.uva.nl
Damming
M
M
Godfried
M H
MH
Boer
K
K
van der Ende
M E
ME
Burger
D M
DM
de Wolf
F
F
Wit
F W N M
FW
Prins
J M
JM
D000328:Adult; D000349:Africa / Q000208:ethnology; D016022:Case-Control Studies; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000188:drug therapy / Q000635:transmission; D015497:HIV-1 / Q000187:drug effects; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control; D008875:Middle Aged; D009426:Netherlands; D019829:Nevirapine / Q000097:blood* / Q000494:pharmacology; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000097:blood* / Q000188:drug therapy; D018894:Reverse Transcriptase Inhibitors / Q000097:blood* / Q000494:pharmacology
D018894:Reverse Transcriptase Inhibitors; D019829:Nevirapine