[Pharmacokinetics of apalcillin in pediatrics]

Apalcillin is a semi-synthetic broad-spectrum penicillin which is particularly active against Pseudomonas. Pharmacokinetic studies were carried out after slow (3 mn) intravenous administration of a single dose of 20 or 30 mg/kg in five categories of infants: premature, dysmature, full term newborn up to 8 days of age, infant aged 8 days to 1 month and infant beyond 1 month. Elimination half-lives in these five groups are respectively: 6.83, 5.44, 5.01, 2.28 and 1.28 hours. A decrease in elimination half-life and increase in total clearance are observed as the infant matures. Renal clearance represents a quarter of total clearance suggesting than there is considerable extrarenal clearance. Pharmacokinetic findings beyond one month of age are comparable to those demonstrated in adults. The dysmature infant is characterized by a significantly lower steady-state distribution volume (p less than or equal to 0.025) as compared to the full term neonate. From these results the recommended dosage is: 20 mg/kg twice daily for premature, dysmature and full term neonates up to 8 days, 30 mg/kg twice daily for infants from 8 days to one month of age, and 30 mg/kg three or four times a day for infants above one month of age.