Study on dissolution and absorption of four dosage forms of isosorbide mononitrate: Level A in vitro–in vivo correlation

The objective of the present study was to develop a novel in vitro system to simulate the process of dissolution and permeation of oral solid dosage forms in vivo, and to establish a correlation between in vitro permeation and in vivo absorption that could predict the bioavailability (BA) and bioequivalence (BE) of congeneric products. The in vitro dissolution and absorption kinetics of four dosage forms of isosorbide mononitrate (ISMN) were evaluated by the USP basket/paddle system and drug dissolution/absorption simulating system (DDASS). The corresponding pharmacokinetic study was performed in beagle dogs. A comparative study was carried out between the classical and the novel method to estimate the effectiveness of the modified DDASS in simulating the course of dissolution and absorption in vivo. Indeed, the correlation coefficients of in vitro dissolution and in vivo absorption obtained from DDASS and dogs were higher. Moreover, a higher level A in vitro–in vivo correlation (IVIVC) between DDASS permeation and dog absorption was established, with correlation coefficients of 0.9968, 0.9872, 0.9921, and 0.9728. The DDASS method was more accurate at modeling the process of dissolution and absorption in vivo for both immediate-release (IR) and sustained-release (SR) dosage forms of ISMN.