EVALUATION OF IN-VITRO IN-VIVO CORRELATION UTILIZING A ROTATING BASKET-PADDLE DISSOLUTION APPARATUS

The desirability of good correlations of parameters derived from in vi tro dissolution study with parameters derived from in vivo bioavailabi lity study is well established in biopharmaceutics. Reports on several in vitro dissolution apparatus, including the two official USP/NF met hods, have appeared in the literature over the years. However, none ha ve been accepted as universal because each apparatus is useful only fo r the dissolution testing of a specific group of drugs or dosage forms . Comparative dissolution testing was performed using the rotating bas ket-paddle apparatus and the two official USP/NF apparatus. A comparat ive bioavailability study was carried out on four batches of rapidly d isintegrating tablets (Formulations A to D) of nitrofurantoin and perp henazine using rabbit as an animal model. Excellent rank order (qualit ative) correlations were observed among all combinations of in vitro a nd in vivo parameters. With the drug nitrofurantoin, an excellent quan titative correlation was found between the dissolution halftime and Cm ax or Tmax or AUC. Yet, a repeated run with perphenazine yielded excel lent correlation between dissolution halftime and Cmax or Tmax, but po or correlation between dissolution halftime and AUC.