Search

A cochleate formulation was developed to enhance the oral bioavailability of revaprazan (RVP). Dimyristoyl phosphatidylcholine (DMPC) liposome containing dicetyl phosphate (DCP) successfully formed a cochleate after treatment with CaCl2, whereas that containing sodium deoxycholate did not. Cochleate was optimised using a D-optimal mixture design with three independent variables—DMPC (X1, 70.58 mol%), cholesterol (X2, 22.54 mol%), and DCP (X3, 6.88 mol%)—and three response variables: encapsulation efficiency (Y1, 76.92%), released amount of free fatty acid at 2 h (Y2, 39.82%), and released amount of RVP at 6 h (Y3, 73.72%). The desirability function was 0.616, showing an excellent agreement between the predicted and experimental values. The cylindrical morphology of the optimised cochleate was visualised, and laurdan spectroscopy confirmed the dehydrated membrane interface, showing an increased generalised polarisation value (approximately 0.5) over small unilamellar vesicle of RVP (RVP-SUV; approximately 0.1). The optimised cochleate showed greater resistance to pancreatic enzyme than RVP-SUV. RVP was released in a controlled manner, achieving approximately 94% release in 12 h. Following oral administration in rats, the optimised cochleate improved the relative bioavailability of RVP by approximately 274%, 255%, and 172% compared to RVP suspension, a physical mixture of RVP and the cochleate, and RVP-SUV, respectively. Thus, the optimised cochleate formulation might be a good candidate for the practical development of RVP. [ABSTRACT FROM AUTHOR]

The recently developed water‐insoluble tegoprazan (TPZ) belongs to the biopharmaceutical classification system (BCS) class II group was formulated through solid dispersion (SD) technology. SD formulations of TPZ were prepared using hydroxymethylcellulose (HPMC) and polyvinylpyrrolidone (PVP) polymers via the solvent evaporation method. SDs were characterized by scanning electron microscopy (SEM), powder x‐ray diffraction (PXRD), and differential scanning calorimetry (DSC). In addition, the equilibrium solubility of SDs, in vitro dissolution, and in vivo bioavailability (BA) study in rats were performed. PXRD and DSC revealed that TPZ was successfully transformed to amorphous forms in SDs. The equilibrium solubility was enhanced by 15–18‐fold, and in vitro dissolution was improved by approximately 2.2‐fold. Consequently, the BA of TPZ was increased up to 2.1‐fold. In conclusion, the use of SDs of TPZ using HPMC and PVP are considered a potential strategy to improve the therapeutic effect of TPZ via enhanced dissolution and BA. [ABSTRACT FROM AUTHOR]

To enhance the dissolution and oral bioavailability of telmisartan (TMS), a poorly water-soluble anti-hypertensive drug, a supersaturable self-microemulsifying drug delivery system (SuSMEDDS) was developed. Amorphous alkalinized TMS (AAT) was formulated into a SMEDDS, composed of Capmul® MCM (oil), Cremophor® RH40 (surfactant), and tetraglycol (co-surfactant). Although the SMEDDS was rapidly dissolved (>80% within 5 min) in a limited condition (500 mL, pH 6.8), drug precipitation was observed over time, resulting in a decrease in dissolution levels. The precipitation was due to drug recrystallization, as determined by differential scanning calorimetry and powder X-ray diffraction analyses. Several polymers, including Soluplus® (SOL), were screened as precipitation inhibitors; ultimately, SuSMEDDS-SOL was prepared by admixing SOL and the SMEDDS at a 5:100 (w/w) ratio. SuSMEDDS-SOL was superior in terms of dissolution efficiency (>90% over 2 h) and dissolution-retaining time (no precipitation over 2 h). An in vivo pharmacokinetic study in rats revealed that the oral bioavailability of SuSMEDDS-SOL was 4.8-, 1.3-, and 1.2-fold greater than those of the TMS suspension, AAT solution, and SMEDDS, respectively. Therefore, SuSMEDDS-SOL is a promising candidate to enhance the dissolution and oral bioavailability of TMS. [ABSTRACT FROM AUTHOR]

Poloxamer 407 (POL) is widely used as a thermosensitive hydrogel for intravesical instillation. When POL hydrogel is instilled in the bladder, several problems, including urinary tract obstruction, are observed. To overcome this problem, a POL‐based floating hydrogel (PFH) system was developed. Sodium bicarbonate (BC) was used as a floating agent. PFH was optimized using a central composite design with two independent variables (X1 [POL concentration, 42.43%] and X2 [BC concentration, 5.23%]) and three response factors (Y1 [floating time, 240.33 s], Y2 [duration time, 270 min], and Y3 [viscosity, 110.39 Pa.s]). In gel erosion and drug‐release studies in vitro, the remaining PFH fraction decreased exponentially with time, while gemcitabine release was biphasic and surface erosion‐controlled. A plot of drug release versus gel erosion showed good linearity. Visual observation for floating, gel duration, and dye release supported the time‐course behaviors of the PFH, indicating its usefulness in intravesical instillation. [ABSTRACT FROM AUTHOR]

Valsartan (VST) is a poorly water-soluble drug and a P-glycoprotein (P-gp) substrate. To enhance the dissolution and oral absorption of VST, a novel supersaturable self-microemulsifying drug delivery system (Su-SMEDDS) was formulated. Based on the previously reported Su-SMEDDS composed of Capmul® MCM (oil), Tween® 20 (T20; surfactant), Transcutol® P (cosurfactant), and Poloxamer 407 (supersaturating agent), P-gp inhibitory surfactants including Tween® 80 (T80) and Cremophor® EL (CR) were newly introduced to replace T20. All Su-SMEDDS formulations had a droplet size of <200 nm and showed rapid (>90% within 5 min) and pH-independent dissolution characteristics. The effective permeability coefficient (Peff) in rat jejunum was obtained using an in situ single-pass intestinal perfusion study: Peff values of Su-SMEDDS-T20, Su-SMEDDS-T80, and Su-SMEDDS-CR were 2.3, 4.1, and 3.4 times greater, respectively, than that of the VST solution. After oral administration of various formulations to rats (equivalent dose of VST 10 mg/kg), plasma drug levels were measured by liquid chromatography-tandem mass spectrometry. The relative bioavailabilities of Su-SMEDDS-T20, Su-SMEDDS-T80, and Su-SMEDDS-CR were 262%, 470%, and 458%, respectively, compared with the VST suspension. Thus, we propose that the Su-SMEDDS-T80 formulation is a good candidate for improving the oral absorption of poorly water-soluble and P-gp substrate drugs such as VST. [ABSTRACT FROM AUTHOR]

To improve the dissolution and oral bioavailability of valsartan (VST), we previously formulated a supersaturable self-microemulsifying drug delivery system (SuSMED) composed of Capmul® MCM (oil), Tween® 80 (surfactant), Transcutol® P (cosurfactant), and Poloxamer 407 (precipitation inhibitor) but encountered a stability problem (Transcutol® P-induced weight loss in storage) after solidification. In the present study, replacing Transcutol® P with Gelucire® 44/14 resulted in a novel SuSMED formulation, wherein the total amount of surfactant/cosurfactant was less than that of the previous formulation. Solidified SuSMED (S-SuSMED) granules were prepared by blending VST-containing SuSMED with selective solid carriers, L-HPC and Florite® PS-10, wherein VST existed in an amorphous state. S-SuSMED tablets fabricated by direct compression with additional excipients were sufficiently stable in terms of drug content and impurity changes after 6 months of storage at accelerated conditions (40 ± 2 °C and 75 ± 5% relative humidity). Consequently, enhanced dissolution was obtained (pH 1.2, 2 h): 6-fold for S-SuSMED granules against raw VST; 2.3-fold for S-SuSMED tablets against Diovan® (reference tablet). S-SuSMED tablets increased oral bioavailability in rats (10 mg/kg VST dose): approximately 177–198% versus raw VST and Diovan®. Therefore, VST-loaded S-SuSMED formulations might be good candidates for practical development in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Objective: To develop an immediate-release tablet preparation containing rebamipide (RBM) and perform the bioavailability assessment in the healthy human subjects., Materials and Methods: Raw RBM powder was characterized using differential scanning calorimetry, powder X-ray diffraction, and scanning electron microscopy (SEM). RBM tablets were manufactured by the wet granulation method, and their dissolution behavior was compared with the reference tablet (Mucosta). A phase I study (n = 47; sequence-randomized, open-label, single-dose, and two-way cross-over design) was designed for oral administration of a test formulation (F4) and Mucosta to healthy human male subjects, and pharmacokinetic parameters including the maximum plasma concentration (C max ) and area under the curve from 0 to 12 hours (AUC 0-12h ) were compared., Results: RBM powder had a multimodal size distribution with typical crystallinity, and the needle-like and elongated morphologies of RBM were visualized using SEM. Various tablet formulations (F1 - F6) were successfully manufactured using wet granulation method. F4 formulation was selected based on the dissolution profile most equivalent to that of Mucosta. F4 was stable for 6 months under accelerated and long-term storage conditions. Based on one-way analysis of variance, the AUC 0-12h (F(1,92) = 2.40, p = 0.13) and t max (F(1,92) = 0.04, p = 0.85) were not significantly different; however, the C max (F(1,92) = 5.45, p = 0.022) showed significant difference between F4 and reference tablets., Conclusion: Despite similar in vitro dissolution profiles, in vivo pharmacokinetic results revealed a partial difference between F4 and reference tablets. Thus, further study on formulation development is still needed.

To improve the dissolution and oral bioavailability of valsartan (VST), we previously formulated a supersaturable self-microemulsifying drug delivery system (SuSMED) composed of Capmul ® MCM (oil), Tween ® 80 (surfactant), Transcutol ® P (cosurfactant), and Poloxamer 407 (precipitation inhibitor) but encountered a stability problem (Transcutol ® P-induced weight loss in storage) after solidification. In the present study, replacing Transcutol ® P with Gelucire ® 44/14 resulted in a novel SuSMED formulation, wherein the total amount of surfactant/cosurfactant was less than that of the previous formulation. Solidified SuSMED (S-SuSMED) granules were prepared by blending VST-containing SuSMED with selective solid carriers, L-HPC and Florite ® PS-10, wherein VST existed in an amorphous state. S-SuSMED tablets fabricated by direct compression with additional excipients were sufficiently stable in terms of drug content and impurity changes after 6 months of storage at accelerated conditions (40 ± 2 °C and 75 ± 5% relative humidity). Consequently, enhanced dissolution was obtained (pH 1.2, 2 h): 6-fold for S-SuSMED granules against raw VST; 2.3-fold for S-SuSMED tablets against Diovan ® (reference tablet). S-SuSMED tablets increased oral bioavailability in rats (10 mg/kg VST dose): approximately 177⁻198% versus raw VST and Diovan ® . Therefore, VST-loaded S-SuSMED formulations might be good candidates for practical development in the pharmaceutical industry.

As a platform for hepsin-specific drug delivery, we previously prepared IPLVVPLRRRRRRRRC peptide (RIPL)-conjugated nanostructured lipid carriers (RIPL-NLCs) composed of Labrafil ® M 1944 CS (liquid oil) and Precirol ® ATO 5 (solid lipid). In this study, to prevent the recognition by the mononuclear phagocyte system, polyethylene glycol (PEG)-modified RIPL-NLCs (PEG-RIPL-NLCs) were prepared using PEG3000 at different grafting ratios (1, 5, and 10 mole %). All prepared NLCs showed a homogeneous dispersion (130⁻280 nm), with zeta potentials varying from -18 to 10 mV. Docetaxel (DTX) was successfully encapsulated in NLCs: encapsulation efficiency (93⁻95%); drug-loading capacity (102⁻109 µg/mg). PEG-RIPL-NLCs with a grafting ratio of 5% PEG or higher showed significantly reduced protein adsorption and macrophage phagocytosis. The uptake of PEG(5%)-RIPL-NLCs by cancer cell lines was somewhat lower than that of RIPL-NLCs because of the PEG-induced steric hindrance; however, the uptake level of PEG-RIPL-NLCs was still greater than that of plain NLCs. In vivo biodistribution was evaluated after tail vein injection of NLCs to normal mice. Compared to RIPL-NLCs, PEG(5%)-RIPL-NLCs showed lower accumulation in the liver, spleen, and lung. In conclusion, we found that PEG(5%)-RIPL-NLCs could be a promising nanocarrier for selective drug targeting with a high payload of poorly water-soluble drugs.