Pharmacokinetics of Clindamycin in Obese and Nonobese Children

ABSTRACT Although obesity is prevalent among children in the United States, pharmacokinetic (PK) data for obese children are limited. Clindamycin is a commonly used antibiotic that may require dose adjustment in obese children due to its lipophilic properties. We performed a clindamycin population PK analysis using data from three separate trials. A total of 420 samples from 220 children, 76 of whom had a body mass index greater than or equal to the 95th percentile for age, were included in the analysis. Compared to other metrics, total body weight (TBW) was the most robust measure of body size. The final model included TBW and a sigmoidal maturation relationship between postmenstrual age (PMA) and clearance (CL): CL (liters/hour) = 13.8 × (TBW/70) 0.75 × [PMA 2.83 /(39.5 2.83 +PMA 2.83 )]; volume of distribution ( V ) was associated with TBW, albumin (ALB), and alpha-1 acid glycoprotein (AAG): V (liters) = 63.6 × (TBW/70) × (ALB/3.3) −0.83 × (AAG/2.4) −0.25 . After accounting for differences in TBW, obesity status did not explain additional interindividual variability in model parameters. Our findings support TBW-based dosing for obese and nonobese children

Clindamycin Pharmacokinetics and Safety in Preterm and Term Infants

ABSTRACT Clindamycin may be active against methicillin-resistant Staphylococcus aureus , a common pathogen causing sepsis in infants, but optimal dosing in this population is unknown. We performed a multicenter, prospective pharmacokinetic (PK) and safety study of clindamycin in infants. We analyzed the data using a population PK analysis approach and included samples from two additional pediatric trials. Intravenous data were collected from 62 infants (135 plasma PK samples) with postnatal ages of 40 to 60 weeks PMA, 9 mg/kg) resulted in an unbound, steady-state concentration at half the dosing interval greater than a MIC for S. aureus of 0.12 μg/ml in >90% of infants. There were no adverse events related to clindamycin use. (This study has been registered at ClinicalTrials.gov under registration no. NCT01728363.

Safety and Effectiveness of Meropenem in Infants With Suspected or Complicated Intra-abdominal Infections

Background. Intra-abdominal infections are common in young infants and lead to significant morbidity and mortality. Meropenem is a broad-spectrum antimicrobial with excellent activity against pathogens associated with intra-abdominal infections. The purpose of this study was to determine the safety and effectiveness of meropenem in young infants with suspected or complicated intra-abdominal infections

Dosing of clopidogrel for platelet inhibition in infants and young children: primary results of the Platelet Inhibition in Children On cLOpidogrel (PICOLO) trial

BACKGROUND: Infants and young children with certain types of heart disease are at increased risk for thromboses. Clopidogrel 75 mg/d is used in adults to prevent thrombotic events. The dose to achieve similar platelet inhibition in children is unknown. The objectives of the present study were (1) to determine the dose of clopidogrel needed in infants and young children to achieve a mean 30% to 50% inhibition of 5-micromol/L ADP-induced platelet aggregation (ie, inhibition similar to that observed with 75 mg in adults) and (2) to assess the safety and tolerability of clopidogrel in infants and young children. METHODS AND RESULTS: We performed a prospective, multicenter, randomized, placebo-controlled trial evaluating the pharmacodynamics of clopidogrel in children (0 to 24 months) with a cardiac condition at risk for arterial thrombosis. Patients were randomized to clopidogrel versus placebo in a 3:1 ratio in 4 sequential groups (0.01, 0.10, 0.20, and 0.15 mg/kg) for \u3e or = 7 and andlt; or = 28 days. Platelet aggregation was assessed at baseline and steady state by light-transmission aggregometry. Of 116 patients enrolled, 92 (50% neonates, 50% infants/toddlers) were randomized, and 73 completed the study. A total of 79% of the randomized and treated patients were taking aspirin. Compared with placebo, clopidogrel 0.20 mg x kg(-1) x d(-1) resulted in a mean 49.3% (95% confidence interval 25.7% to 72.8%) inhibition of the maximum extent of platelet aggregation and a mean 43.9% (95% confidence interval 18.6% to 69.2%) inhibition of the rate of platelet aggregation. There was marked interpatient variability in the degree of platelet aggregation inhibition within each treatment-dose group and age group. No serious bleeding events occurred. CONCLUSIONS: Clopidogrel 0.20 mg x kg(-1) x d(-1) in children 0 to 24 months of age achieves a platelet inhibition level similar to that in adults taking 75 mg/d. Clopidogrel is well tolerated in infants and young children at this dose

Drug dosing and pharmacokinetics in children with obesity a systematic review

IMPORTANCE Obesity affects nearly one-sixth of US children and results in alterations to body composition and physiology that can affect drug disposition, possibly leading to therapeutic failure or toxic side effects. The depth of available literature regarding obesity's effect on drug safety, pharmacokinetics, and dosing in obese children is unknown. OBJECTIVE To perform a systematic literature review describing the current evidence of the effect of obesity on drug disposition in children. EVIDENCE REVIEW We searched the MEDLINE, Cochrane, and EMBASE databases (January 1, 1970-December 31, 2012) and included studies if they contained data on drug clearance, volume of distribution, or drug concentration in obese children (aged≤18 years).We compared exposure and weight-normalized volume of distribution and clearance between obese and nonobese children.We explored the association between drug physicochemical properties and clearance and volume of distribution. FINDINGS Twenty studiesmet the inclusion criteria and contained pharmacokinetic data for 21 drugs. The median number of obese children studied per drug was 10 (range, 1-112) and ages ranged from newborn to 29 years (1 study described pharmacokinetics in children and adults together). Dosing schema varied and were either a fixed dose (6 [29%]) or based on body weight (10 [48%]) and body surface area (4 [19%]). Clinically significant pharmacokinetic alterations were observed in obese children for 65%(11 of 17) of the studied drugs. Pharmacokinetic alterations resulted in substantial differences in exposure between obese and nonobese children for 38%(5 of 13) of the drugs.We found no association between drug lipophilicity or Biopharmaceutical Drug Disposition Classification System class and changes in volume of distribution or clearance due to obesity. CONCLUSIONS AND RELEVANCE Consensus is lacking on the most appropriate weight-based dosing strategy for obese children. Prospective pharmacokinetic trials in obese children are needed to ensure therapeutic efficacy and enhance drug safety

Effect of Fluconazole Prophylaxis on Candidiasis and Mortality in Premature Infants

IMPORTANCE: Invasive candidiasis in premature infants causes mortality and neurodevelopmental impairment. Fluconazole prophylaxis reduces candidiasis, but its effect on mortality and the safety of fluconazole is unknown. OBJECTIVE: To evaluate the efficacy and safety of fluconazole in preventing death or invasive candidiasis in extremely low-birth-weight infants. DESIGN, SETTING, AND PATIENTS: This study was a randomized, blinded, placebo-controlled trial of fluconazole in premature infants. Infants weighing less than 750 g at birth (N = 361) from 32 neonatal intensive care units (NICUs) in the United States were randomly assigned to receive either fluconazole or placebo twice weekly for 42 days. Surviving infants were evaluated at 18 to 22 months corrected age for neurodevelopmental outcomes. The study was conducted between November 2008 and February 2013. INTERVENTIONS: Fluconazole (6 mg/kg of body weight) or placebo. MAIN OUTCOMES AND MEASURES: The primary end point was a composite of death or definite or probable invasive candidiasis prior to study day 49 (1 week after completion of study drug). Secondary and safety outcomes included invasive candidiasis, liver function, bacterial infection, length of stay, intracranial hemorrhage, periventricular leukomalacia, chronic lung disease, patent ductus arteriosus requiring surgery, retinopathy of prematurity requiring surgery, necrotizing enterocolitis, spontaneous intestinal perforation, and neurodevelopmental outcomes—defined as a Bayley-III cognition composite score of less than 70, blindness, deafness, or cerebral palsy at 18–22-months corrected age. RESULTS: Among infants receiving fluconazole, the composite primary end point of death or invasive candidiasis was 16% (95% CI, 11%–22%) vs 21% in the placebo group (95% CI, 15%–28%; odds ratio 0.73 [95% CI 0.43–1.23]; P=.24; treatment difference −5% [95% CI, −13%–3%]). Invasive candidiasis occurred less frequently in the fluconazole group (3% [95% CI, 1%–6%] vs the placebo group (9% [95% CI, 5%–14%]; P=.02; treatment difference −6% [95% CI, −11%–−1%]). The cumulative incidences of other secondary outcomes were not statistically different between groups. Neurodevelopmental impairment did not differ between the groups (fluconazole 31% [95% CI, 21–41%] vs placebo, 27% [95% CI, 18–37%]; P=.60; treatment difference 4% [95% CI, −10–17%]). CONCLUSIONS AND RELEVANCE: Among infants with a birth weight of less 750 g, 42 days of fluconazole prophylaxis compared with placebo did not result in a lower incidence of the composite of death or invasive candidiasis. These findings do not support the universal use of prophylactic fluconazole in extremely-low-birth-weight infants. TRIAL REGISTRATION: ClinicalTrials.gov number NCT0073453