{"title":"Amalgam of ternary solid dispersion and P-gp efflux inhibition in development of colon-targeted tablets of rifaximin","authors":"M. Lalan, P. Shah, Ruchita Kadam, H. Patel","doi":"10.4103/jrptps.jrptps_21_22","DOIUrl":null,"url":null,"abstract":"Background: Rifaximin, a BCS class IV drug, possesses low bioavailability due to low solubility and low permeability attributable to P-gp efflux. The studies attempted to develop pH-sensitive rifaximin tablets based on ternary solid dispersion (TSD) for spatial and temporal drug release in colon. Materials and Methods: Rifaximin TSD was prepared using Neusilin US2 as a mesoporous carrier and Poloxamer 188 as a hydrophilic carrier and P-gp inhibitor by solvent evaporation technique employing acetone at 1:5 ratio. The TSD was assessed for P-gp inhibition using the gut sac method and Caco-2 permeability studies. The TSD was compressed into tablets and coated with pH-sensitive polymers. Coating optimization was carried out using a 32 factorial design, wherein % coating and ratio of Eudragit S100:Eudragit L100 were the independent variables and % drug release at 2 h and % drug release at 8 h were the dependent variables. Results: Differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy studies of rifaximin TSD suggested amorphization of the drug. Gut sac studies indicated higher mucosal to serosal permeability of rifaximin from TSD. Caco-2 permeability studies demonstrated a 4.83-fold higher permeability of rifaximin from TSD (polaxamer 25% w/w and Neusilin 55% w/w of TSD) and a significant change in efflux ratio. In-vitro release studies of the coated tablets displayed controlled and site-specific release at pH of the colon. Conclusion: Effective, stable, pH-dependent rifaximin colon-targeted tablets with enhanced dissolution, permeability, and reduced P-gp efflux were developed. The achieved merits could translate into augmented bioavailability and dose reduction. Further in-vivo studies on this novel formulation, which is cost-effective and industrially scalable, can improve the pharmacoeconomics of inflammatory bowel disease management.","PeriodicalId":16966,"journal":{"name":"Journal of Reports in Pharmaceutical Sciences","volume":"11 1","pages":"222 - 235"},"PeriodicalIF":0.7000,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Reports in Pharmaceutical Sciences","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.4103/jrptps.jrptps_21_22","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PHARMACOLOGY & PHARMACY","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Rifaximin, a BCS class IV drug, possesses low bioavailability due to low solubility and low permeability attributable to P-gp efflux. The studies attempted to develop pH-sensitive rifaximin tablets based on ternary solid dispersion (TSD) for spatial and temporal drug release in colon. Materials and Methods: Rifaximin TSD was prepared using Neusilin US2 as a mesoporous carrier and Poloxamer 188 as a hydrophilic carrier and P-gp inhibitor by solvent evaporation technique employing acetone at 1:5 ratio. The TSD was assessed for P-gp inhibition using the gut sac method and Caco-2 permeability studies. The TSD was compressed into tablets and coated with pH-sensitive polymers. Coating optimization was carried out using a 32 factorial design, wherein % coating and ratio of Eudragit S100:Eudragit L100 were the independent variables and % drug release at 2 h and % drug release at 8 h were the dependent variables. Results: Differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy studies of rifaximin TSD suggested amorphization of the drug. Gut sac studies indicated higher mucosal to serosal permeability of rifaximin from TSD. Caco-2 permeability studies demonstrated a 4.83-fold higher permeability of rifaximin from TSD (polaxamer 25% w/w and Neusilin 55% w/w of TSD) and a significant change in efflux ratio. In-vitro release studies of the coated tablets displayed controlled and site-specific release at pH of the colon. Conclusion: Effective, stable, pH-dependent rifaximin colon-targeted tablets with enhanced dissolution, permeability, and reduced P-gp efflux were developed. The achieved merits could translate into augmented bioavailability and dose reduction. Further in-vivo studies on this novel formulation, which is cost-effective and industrially scalable, can improve the pharmacoeconomics of inflammatory bowel disease management.
期刊介绍:
The Journal of Reports in Pharmaceutical Sciences(JRPS) is a biannually peer-reviewed multi-disciplinary pharmaceutical publication to serve as a means for scientific information exchange in the international pharmaceutical forum. It accepts novel findings that contribute to advancement of scientific knowledge in pharmaceutical fields that not published or under consideration for publication anywhere else for publication in JRPS as original research article. all aspects of pharmaceutical sciences consist of medicinal chemistry, molecular modeling, drug design, pharmaceutics, biopharmacy, pharmaceutical nanotechnology, pharmacognosy, natural products, pharmaceutical biotechnology, pharmacology, toxicology and clinical pharmacy.