Author(s): G.N. Darwhekar*, Dr. D.K Jain and Arpit Kapoor.
Literature survey reveals that, amoebiasis is the second leading cause of death from parasitic disease worldwide. The causative protozoan parasite, Entamoeba histolytica, is a potent pathogen. Oral delivery of drugs in the colon is valuable in the treatment of diseases of colon like amoebiasis whereby high local concentration can be achieved while minimizing side effects. Satranidazole was selected as the drug of choice because it is most potent nitroimidazole derivative and clinically useful against common protozoa; it is twice as effective as other nitroimidazole against amoebiasis. Colon targeted tablet of satranidazole can maintain minimum inhibitory concentration (MIC90) for desired duration in fewer doses and even with fewer side effects. The colon targeted matrix tablet of satranidazole which is composed of polysaccharides which are susceptible to enzymatic degradation i.e. Guar gum, Xanthan gum, Guar: Xanthan gum in combination at 2 ratios (1:1) and (2:1) and Pectin coated with enteric polymer Eudragit L, Eudragit S and Eudragit RS in ratio of 4:16:5 with less quantity of plasticizer PEG 400 showed excellent film properties and were able to release most of the drug into colon. 10% of coating was found to be optimum. Analytical methods were developed for the drug, and calibration curves were prepared in SGF, SIF, and SCF. Formulation SF7 was considered as optimum batch as it delivered 96 % of drug into colon. The in vivo studies showed that tablet does not disintegrate in stomach and small intestine and site of disintegration was found to be descending colon. The formulation SF7 can be employed as a promising colon specific drug delivery system of satranidazole.