In-Vitro Binding Studies Services

The BE approach is not applicable for Locally Acting Gastro Intestinal Drugs since they are not intended to be absorbed into the systemic circulation and thus, drug concentration needs to be estimated at the local GI tract site. These drugs dissociate in the acid environment of the upper GI tract to release ionic drug species that bind to dietary phosphate or bile acids to form an insoluble complex that is eliminated via feces.

In-vitro studies are not a mere Analytical comparison between the test and reference. These studies are considered as substitute to clinical trial. USFDA has developed product specific guidelines for In-vitro BE studies i.e to compare the extent and rate of binding affinity between Test and Reference formulations where Assay to be performed with minimum 12 replicates at various pH conditions. It also includes equilibrium binding study with or without acid pretreatment and measurements of pH at different time points.