Establishing In Vitro-In Vivo Correlation (IVIVC) for Formulations of Vitamin C and Iron in Daily Plus Tablets

Introduction:The aim of this study was to establish an in vitro-in vivo correlation (IVIVC) model for ferrous fumarate (iron) and ascorbic acid (vitamin C).Methods: In vitro dissolution data from 13 samples of a multinutrient botanical formulation containing iron and vitamin C (Daily Plus extended-release tablets) were analyzed using mathematical models to estimate the absorption kinetics of vitamin C and iron in vivo following oral administration.Plasma concentrations were estimated for both iron and vitamin C from the generated models.Results: Our analysis revealed a quadratic and a linear relationship between in vivo absorption and in vitro dissolution rates for both vitamin C and iron, respectively, indicating that the dissolution rate of these compounds in vitro is a critical factor affecting their absorption kinetics in vivo.Furthermore, we found that the IVIVC model correlation is specific to the formulation, as different formulations may have different absorption kinetics and IVIVC models.By leveraging this quadratic relationship, we were able to make precise predictions of the entire pharmacokinetic profile based solely on in vitro dissolution data for the formulation.Conclusion: A robust IVIVC (level A) was established for vitamin C and iron release from Daily Plus tablets.This correlation can serve as a surrogate bioequivalence studies.