Understanding the Impact of Age-Related Changes in Pediatric GI Solubility by Multivariate Data Analysis

Abstract

The aim of this study was to understand drug solubilization as a function of age and identify drugs at risk of altered drug solubility in newborns and young infants in comparison to adults. Multivariate statistical analysis was used to understand drug solubilization as a function of drug’s physicochemical properties and the composition of gastrointestinal fluids. The solubility of seven poorly soluble compounds was assessed in adult and age-specific fasted and fed state biorelevant media. Partial least squares regression (PLS-R) was used to assess the influence of (i) drug physicochemical properties and (ii) age-related changes in simulated GI fluids, as well as (iii) their interactions, on the pediatrics-to-adult solubility ratio (Sp/Sa (%)). For five out of seven of the compounds investigated, Sp/Sa (%) values fell outside of the 80–125% limits in at least one of the pediatric media. Lipophilicity was responsible for driving drug solubility differences between adults and children in all the biorelevant media investigated, while drug ionization was most relevant in the fed gastric media, and the fasted/fed intestinal media. The concentration of bile salts and lecithin in the fasted and fed intestinal media was critical in influencing drug solubility, while food composition (i.e., cow’s milk formula vs. soy formula) was a critical parameter in the fed gastric state. Changes in GI fluid composition between younger pediatric patients and adults can significantly alter drug luminal solubility. The use of pediatric biorelevant media can be helpful to identify the risk of altered drug solubilization in younger patients during drug development.

Assessment of Inter-Individual Pharmacokinetic Variability of Voriconazole Based on Bile Salt Disparities using POP-PK Modeling

“…The earliest years of life, where there are the most variances, are of particular interest. [24][25][26][27][28][29] The ratios of intestinal bile salt concentrations seen in newborns, infants, and adults in relation to glycine/taurine varied from newborns to infants (7-12 months) to adults in the range of 0.5 to 2.4 to 3.1, respectively. 30 In addition, crucial components of the "patient-centric drug development" process are thought to include in-vitro dissolution studies conducted in age-specific biorelevant media coupled with physiologically based pharmacokinetic (PBPK) models.…”