Abstract

ROLE OF HYDROPHILIC POLYMERS ON GASTRO RETENTIVE FLOATING DRUG DELIVERY SYSTEMS OF FAMCICLOVIR

Srinath S, Preethi N*, Sivaneshwari S, Mounika B, Naveen Kumar B, Hemalatha G,Vasudeva Murthy S.

Abstract

In the present study, gastro retentive floating drug delivery system (GRDDS) of Famciclovir, an antiviral drug, with an oral bioavailability of only 75% have been designed to increase therapeutic efficacy and gastric residence time and to reduce frequency of administration. Famciclovir having a short biological half life of 2.5hrs is eliminated quickly from the body leading to low efficacy. Therefore a sustained release medication was advantageous so as to achieve prolonged therapeutic effect and to reduce peak and retentive valley effect in plasma concentration. This can be achieved by formulating gastro retentive sustained release dosage forms which resides in the stomach for sufficient time to release the drug. The tablets were prepared by direct compression method by employing HPMC grade polymers (HPMCK4M, HPMCK15M and HPMCK100M) in various concentrations. The pre compression and post compression parameters were evaluated including floating time, floating lag time, swelling behavior and in-vitro dissolution studies. All the formulations showed good results which were compliance with the Pharmacopoeial standards. An in-vitro dissolution study was carried out in 0.1 N HCl. From the in-vitro dissolution studies, it has been found that the increase in polymer concentration decreased the drug release. The in-vitro cumulative percentage drug release of all formulations ranged from 79.9%-95.99% at the end of 12hrs. All the formulations showed a floating lag time of less than 64 sec and with a floating time of more than 12 hrs. Among the different formulations, formulation (F4) exhibited controlled and prolonged drug release. The in-vitro drug release kinetics of the optimized formulation (F4) followed first order kinetics with non- fickian release mechanism.

Keywords: Famciclovir; Gastric retention; Floating tablets; Hydroxypropylmethylcellulose