Ja. Stiskal et al., Functional and antigenic concentrations of alpha-1-proteinase inhibitor after administration for the prevention of chronic lung disease of prematurity, BIOL NEONAT, 76(3), 1999, pp. 134-143
Objective and Methods: Alpha-1-proteinase inhibitor (A1PI) supplementation
has been used in adults with inherited alpha-1-antitrypsin (A1AT) deficienc
y to impede the development of emphysema. A1PI supplementation may also be
useful for protecting premature neonates who receive mechanical ventilation
from the development of chronic lung disease (CLD). However, the pharmacok
inetics of exogenous A1PI in this population are unknown. We attempted to d
etermine the disposition of A1PI in premature infants with birth weight 600
-1,250 g who received 60 mg/kg on days 0, 4, 7 and 14 in a randomized, plac
ebo-controlled, double-blind trial. Functional and antigenic plasma concent
rations of A1PI were measured at specified time points. Results: On both fu
nctional and antigenic assays, concentrations began in the normal adult ran
ge and rose from day 0 to 10 then fell slightly, but remained above initial
values. The concentrations were not significantly different between the tr
eatment and placebo groups. Conclusions: The results of this study indicate
that neonatal pharmacokinetics of A1PI differ markedly from those of the a
dult. Total plasma clearance of exogenous A1PI seems high in the ventilated
premature neonate. Higher or more frequent doses may be necessary to maint
ain A1PI plasma concentrations above baseline.