THE CUTOFF TIME POINT OF THE PARTIAL AREA METHOD FOR ASSESSMENT OF RATE OF ABSORPTION IN BIOEQUIVALENCE STUDIES

The partial area method has been suggested for the assessment of the a bsorption rate in bioequivalence studies. This paper provides a theore tical basis for the estimation of the optimal cutoff time point of the partial areas for drugs with one compartment model disposition. The a nalysis is performed by using the appropriate equations which relate t he normalized (in terms of the extent of absorption) partial areas wit h time expressed in terms of multiples of half-life. Provided that the quality of experimental data ensures precise estimation of the parame ters, the t(max) of the formulation with the faster absorption charact eristics is generally the most practical cutoff time point for calcula tion of the normalized partial areas, when a drug follows one compartm ent model disposition with linear absorption.