The effects of pharmaceutical excipients on intestinal drug absorption have been highlighted and careful excipient selection is required to develop biologically equivalent formulations. This study aimed to evaluate the effects of excipients on drug permeability and compare the characteristics of in vitro screening methods. Three in vitro models, the commercial precoated parallel artificial membrane permeability assay (PAMPA), PermeaPad, and Caco-2 monolayer, were used to evaluate the effects of 14 excipients on the permeability of several drugs with different biopharmaceutical classification system classes.
View Article and Find Full Text PDFThe development of generic pharmaceuticals involves a bioequivalence study to ensure the therapeutic equivalence of the test formulation to the original innovative product. The formulation characteristics of generic products are expected to be maintained in the long term after approval. This study analyzed the factors contributing to the changes in the dissolution profiles of approved products during their life cycles.
View Article and Find Full Text PDFAAPS PharmSciTech
December 2023
The use of apex vessels may solve coning problems associated with dissolution testing. However, excessive dissolution acceleration can reduce the discriminatory power. This study aimed to clarify how different apex vessel sizes affect the dissolution behavior of cone-forming formulations.
View Article and Find Full Text PDFJabara juice and its component narirutin inhibit the activity of organic anion-transporting polypeptides (OATPs) 1A2 and OATP2B1, which are considered to play significant roles in the intestinal absorption of fexofenadine. In this study, we investigated the effects of jabara juice on the intestinal absorption of fexofenadine in mice and the inhibitory effects of jabara juice and narirutin on the permeation of fexofenadine using Caco-2 cell monolayers and LLC-GA5-COL300 cell monolayers. In the in vivo study, the area under the plasma concentration-time curve (AUC) of fexofenadine in mice was increased 1.
View Article and Find Full Text PDFGovernment campaigns to replace off-patent brand pharmaceuticals with low cost generic products in national health insurance systems have apparently increased their production in the last two decades in Japan. The contamination of a batch of generic itraconazole tablets with the sleep inducer rilmazafone caused significant adverse events and related accidents in 2020, amidst increasing use of the generic products in healthcare. Investigations revealed many Good Manufacturing Practice (GMP) violations and other evidence of poor quality management in the manufacturing/marketing authorization holder (MAH).
View Article and Find Full Text PDFLittle is known about the influence of non-synonymous genetic variations in the organic anion-transporting polypeptide (OATP) 1A2 on the transport kinetics of its substrate fexofenadine. Moreover, the pH-dependency of fexofenadine uptake also remains unclear. This study aimed to evaluate the effects of genetic variants (Ile13Thr, Asn128Tyr, Glu172Asp, Ala187Thr, and Thr668Ser) on the OATP1A2-mediated uptake of fexofenadine at pH 6.
View Article and Find Full Text PDFNon-synonymous genetic variants of organic anion-transporting polypeptide (OATP) 1A2 with altered transport activity have been identified. Naringin and narirutin, which are found in grapefruit, and their aglycon naringenin inhibit OATP1A2. However, their inhibitory effects on OATP1A2 variants have not been investigated, nor has the influence of their molecular structure, such as the number of sugar moieties, on their inhibitory potency.
View Article and Find Full Text PDFOrganic anion-transporting polypeptide (OATP) 1A2 and OATP2B1 mediate the intestinal absorption of drugs. This study aimed to identify fruit juices or fruit juice components that inhibit OATPs and assess the risk of associated food-drug interactions. Inhibitory potency was assessed by examining the uptake of [H]estrone 3-sulfate and [H]fexofenadine into HEK293 cells expressing OATP1A2 or OATP2B1.
View Article and Find Full Text PDFDrug Metab Pharmacokinet
December 2021
Organic anion transporting polypeptide (OATP) 2B1 is expressed in the intestine and liver, and OATP2B1-mediated transport of estrone 3-sulfate is pH-dependent and consists of: the high-affinity component (Hc) and low-affinity component (Lc). This study aimed to evaluate the influence of pH on the transport kinetics of each component, along with the inhibitory nature of ten OATP2B1 inhibitors. The Michaelis constants (K) were 4-fold and 1.
View Article and Find Full Text PDFStereocontrolled syntheses of biotin-labeled oligosaccharide portions containing the carbohydrate moiety of glycoprotein from have been accomplished. Trisaccharide Galβ1-3Galβ1-3GalNAcα1-R (), tetrasaccharide Galα1-4Galβ1-3Galβ1-3GalNAcα1-R (), and pentasaccharide Galα1-4Galβ1-3Galβ1-3Galβ1-3GalNAcα1-R (), (R = biotinylated probe) were synthesized by stepwise condensation and/or block synthesis by the use of 5-(methoxycarbonyl)pentyl 2-azido-4,6--benzylidene-2-deoxy-α-d-galactopyranoside as a common glycosyl acceptor. The synthesis of the tetrasaccharide and the pentasaccharide was improved from the viewpoint of reducing the number of synthetic steps and increasing the total yield by changing from stepwise condensation to block synthesis.
View Article and Find Full Text PDFOrganic anion-transporting polypeptides (OATPs) 1A2 and OATP2B1 are expressed in the small intestine and are involved in drug absorption. We identified narirutin, which is present in grapefruit juice, as a novel OATP inhibitor. The citrus fruit jabara also contains high levels of narirutin; therefore, we investigated the inhibitory potency of jabara juice against OATPs.
View Article and Find Full Text PDFDrug Metab Pharmacokinet
April 2020
Organic anion-transporting polypeptide (OATP) 1A2 is expressed on the apical sides of intestinal and renal epithelial cells and considered to be involved in the intestinal absorption and renal reabsorption of drugs. Although the transport activity of OATP1A2 is considered to be pH-dependent, the effects of pH on its kinetic parameters and on the potency of OATP1A2 inhibitors are yet to be elucidated. Some OATP are known to have multiple binding sites (MBS), but it remains unclear whether OATP1A2 has MBS.
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