Development and Evaluation of Controlled Release Gastroretentive Drug Delivery System for Clarithromycin

The objective here was to develop gastroretentive tablets of clarithromycin to provide increased residence time in stomach for delivery of antibiotic to treat H. pylori induced gastric ulcers. Hydroxypropylmethylcellulose K4M (HPMC) was used as a mucoadhesive polymer and Avicel PH101 was used as the release modifier. Tablets containing drug, HPMC and Avicel PH101 were prepared using wet granulation technique. The tablets were evaluated for in vitro drug release profile and ex vivo bioadhesion property. A 3^2 factorial design was employed to study the influence of amount of HPMC (X1) and amount of Avicel PH101 (X2) on drug release at the end of 2nd hour (Y1), 6th hour (Y2) and 10th hour (Y3) from the mucoadhesive tablets. Target release profile was generated for a 12 hour dosage regimen and dissolution profile of the best batch was compared using similarity factor f2. Results of multiple regression analysis indicated that HPMC reduced the drug release at all time points while! Avicel PH101 increased the amount of drug release. The dissolution profile of the optimum batch had the similarity factor value of 61 indicating that the release profile was similar to that of target release profile. No significant interaction was found between the drug and the polymer as indicated by DSC and FTIR study. The in vitro drug release followed Korsmeyer and Peppas model kinetics and the drug release mechanism was found to be of anomalous or non-Fickian type (n = 0.837). Gastroretentive tablets for twice a day dosing could be developed for clarithromycin.