口服自微乳给药系统的研究进展

自微乳给药系统能够显著提高水难溶性药物的口服生物利用度,且最终的给药形式多样,在推进高生物利用度口服递药系统的发展中,表现出良好的应用前景。但自微乳给药系统也存在诸如存储运输不便、稳定性不佳、体外释药评价局限等问题。随着近年来新型载体材料和制剂技术的发展,对固体自微乳给药系统、过饱和自微乳给药系统等新型制剂的研究日益增多,在弥补传统自微乳给药系统不足的同时,可发挥自微乳给药系统的优势。综述自微乳给药系统的辅料组成、促进药物口服吸收的机制、固化方法及体外释药评价方法的研究进展。     

A Novel Nanocapsule Delivery System to Overcome Intestinal Degradation and Drug Transport Limited Absorption of P-glycoprotein Substrate Drugs

PURPOSE: To design a double-coated nanoparticulate delivery system of tacrolimus capable of overcoming the P-glycoprotein pump and CYP3A barriers without affecting their physiological activities. MATERIALS AND METHODS: Tacrolimus loaded oil cores were first nanoencapsulated with two polymethacrylate polymers followed by the microencapsulation of these nanocapsules within hydroxypropylmethylcellulose using a spray drying technique. The Trojan effect of these double-coated nanocapsules was evaluated in Caco-2 monolayer by monitoring the tacrolimus uptake and measuring the transport of tacrolimus across the rat jejunum membrane. RESULTS: The formulation was shown to release nanocapsules rather than dissolved drug under sink conditions. The nanocapsules protected tacrolimus from degradation in the diluted intestinal fluids following 2 h incubation. The Caco-2 and intestinal segment uptake of tacrolimus from the novel delivery system with and without verapamil was significantly higher than the uptake of tacrolimus from the aqueous solution and emulsion. The blank drug delivery system did not inhibit the P-gp pump activity. The nanocapsules internalized rapidly in the enterocytes as confirmed by the histological results. CONCLUSION: The overall results suggest that the novel nanodelivery system which does not alter the activity of the P-gp is a potential platform for intestinal transport of sensitive lipophilic molecules that are P-gp substrates.     

自微乳药物传递系统的研究进展

综述了自微乳药物传递系统的最新研究进展，并详细阐述了该系统的主要特点、形成机制、处方组成、体内外评价和影响口服制剂生物利用度的因素，并介绍了近年来该药物传递系统的应用研究情况。     

齐墩果酸自微乳化给药系统的制备及其体外溶出度考察

目的:制备齐墩果酸-自微乳化给药系统(OA-SMEDDS)并考察其体外溶出度。方法:以聚氧乙烯(35)蓖麻油等为辅料制备OA-SMEDDS;采用高效液相色谱法测定制剂中OA含量;以0.5%十二烷基硫酸钠为溶出介质、转速100r·min-1、桨法测定制剂的体外溶出度,并与上市OA片剂比较。结果:所制微乳液滴呈圆球形,平均粒径为48.5nm,平均含量为9.29mg·mL-1;OA-SMEDDS软胶囊15min累积溶出度达85%以上,而上市片剂60min时未达60%。结论:与上市片剂相比,SMEDDS显著改善了药物的溶出度,为进一步提高OA制剂的口服生物利用度奠定了基础。     

难溶性药物盐酸奈必洛尔口服自微乳化给药系统的制备以及体外评价

目的 制备盐酸奈必洛尔(hydrochloride,NBH)自微乳化给药系统(self-microemulsifying drug delivery system,SMEDDS),并进行体外评价。方法 通过测定NBH在不同油相、表面活性剂和助表面活性剂中的溶解度以及运用伪三元相图对空白自微乳化的处方组成进行确定,使用星点设计-效应面法对处方用量进行筛选和优化,并加入过量NBH原料药对该处方的载药量进行确定。结果 NBH-SMEDDS处方组成为中链甘油三酸酯∶辛酸癸酸聚乙二醇甘油酯∶二乙二醇单乙基醚=20∶48∶32,该处方的载药量为20.05 mg,该处方的粒径、自乳化时间、粒径分布范围符合预测值,溶出度试验显示,NBH-SMEDDS在介质中溶出度的整体趋势对比NBH粉末和NBH普通片有一定的提升,在1,2,3月的加速条件下稳定性良好。结论 SMEDDS可用于提高NBH的体外溶出度,且稳定性良好。     

Tumor Targeting Synergistic Drug Delivery by Self-Assembled Hybrid Nanovesicles to Overcome Drug Resistance

Purpose

To overcome multi-drug resistance (MDR) in tumor chemotherapy, a polymer/inorganic hybrid drug delivery platform with tumor targeting property and enhanced cell uptake efficiency was developed.

Method

To evaluate the applicability of our delivery platform for the delivery of different drug resistance inhibitors, two kinds of dual-drug pairs (doxorubicin/buthionine sulfoximine and doxorubicin/tariquidar, respectively) were loaded in heparin-biotin/heparin/protamine sulfate/calcium carbonate nanovesicles to realize simultaneous delivery of an anticancer drug and a drug resistance inhibitor into drug-resistant tumor cells.

Results

Prepared by self-assembly, the drug loaded hybrid nanovesicles with a mean size less than 210 nm and a negative zeta potential exhibit good stability in serum contained aqueous media. The in vitro cytotoxicity evaluation indicates that hybrid nanovesicles with tumor targeting biotin moieties have an enhanced tumor cell inhibitory effect. In addition, dual-drug loaded hybrid nanovesicles exhibit significantly stronger cell growth inhibition as compared with doxorubicin (DOX) mono-drug loaded nanovesicles due to the reduced intracellular glutathione (GSH) content by buthionine sulfoximine (BSO) or the P-glycoprotein (P-gp) inhibition by tariquidar (TQR).

Conclusions

The tumor targeting nanovesicles prepared in this study, which can simultaneously deliver multiple drugs and effectively reverse drug resistance, have promising applications in drug delivery for tumor treatments. The polymer/inorganic hybrid drug delivery platform developed in this study has good applicability for the co-delivery of different anti-tumor drug/drug resistance inhibitor pairs to overcome MDR.

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Graphical Abstract A polymer/inorganic hybrid drug delivery platform with enhanced cell uptake was developed for tumor targeting synergistic drug delivery. The heparin-biotin/heparin/protamine sulfate/calcium carbonate nanovesicles prepared in this study can deliver an anticancer drug and a drug resistance inhibitor into drug-resistant tumor cells simultaneously to overcome drug resistance efficiently.

     

辅酶Q10自微乳化释药系统的制备及稳定性研究

筛选辅酶Q10自微乳化释药系统(CoQ10-SMEDDS)的处方并考察其稳定性。通过溶解度实验筛选油相、表面活性剂和助表面活性剂;绘制三元相图,以乳化时间、乳化效果和乳滴粒径大小为指标,确定最佳处方及配比;考察CoQ10-SMEDDS在各处理条件下的稳定性。CoQ10-SMEDDS最佳处方配比为油酸乙酯∶Cremo-phor EL∶PEG400为18∶35∶7,自乳化形成平均粒径为30.9 nm的微乳。所制备的CoQ10-SMEDDS对CoQ10的溶解度大,自乳化效果好,乳滴粒径小,稳定性高。     

鼻腔给药系统的鼻粘膜毒性及解决途径

就鼻腔给药系统可能导致的鼻粘膜毒性的评价方法、易产生毒性的制剂组分及解决毒性的方法进行简要的综述。     

Intestinal Patches for Oral Drug Delivery

Purpose. Oral route offers an attractive mode of drug administration, although its applications are limited by poor stability of peptides and proteins in the gastrointestinal tract. In this article, we report a novel method based on intestinal patches for oral drug delivery. This method involves the use of millimeter size mucoadhesive patches that adhere to the intestinal wall and direct solute diffusion towards the wall similar to that observed in the case of a transdermal patch. Methods. Intestinal patches were prepared by sandwiching a film of cross-linked bovine serum albumin microspheres between a film of ethyl cellulose and Carbopol/pectin. Delivery of three model drugs, sulforhodamine B, phenol red, and dextran was assessed in vitro using rat intestine. Results. In vitro tests confirmed substantial unidirectional diffusion of model drugs from the patch across the intestinal wall. The presence of ethyl cellulose layer minimized release from the edges as well as from the back side of the patch into the intestinal lumen. In vitro experiments with rat intestine showed that patches were effective in delivering model drugs across the intestine. Trans-lumenal flux of model drugs from intestinal patches was about 100-fold higher compared to that from a solution due to localization of the solute near the intestinal wall and due to minimization of drug loss into the intestinal lumen. Conclusions. Intestinal patches offer a novel approach for oral drug delivery.     

眼表局部给药的屏障及克服屏障的方法研究进展

眼部结构的复杂性使药物经眼表局部给药的生物利用度极低。基于纳米制剂的新型眼部药物递送系统,因其更易克服眼部给药屏障,使得药物经眼表局部给药后有效递送至眼组织内成为可能。介绍了眼表局部给药后药物递送至眼内需克服的屏障,总结了克服给药屏障的重要方法及眼用新剂型的临床进展,并对眼表局部给药系统的前景进行了展望,以期为眼部疾病的治疗提供新思路。     

Enhanced Oral Absorption of Paclitaxel in a Novel Self-Microemulsifying Drug Delivery System with or Without Concomitant Use of P-Glycoprotein Inhibitors

PURPOSE: The objective of this study was to evaluate the pharmacokinetics of paclitaxel in a novel self-microemulsifying drug delivery system (SMEDDS) for improved oral administration with or without P-glycoprotein (P-gp) inhibitors. METHODS: Paclitaxel SMEDDS formulation was optimized, in terms of droplet size and lack of drug precipitation following aqueous dilution, using a ternary phase diagram. Physicochemical properties of paclitaxel SMEDDS and its resulting microemulsions were evaluated. The plasma concentrations of paclitaxel were determined using a HPLC method following paclitaxel microemulsion administrations at various doses in rats. RESULTS: Following 1:10 aqueous dilution of optimal paclitaxel SMEDDS, the droplet size of resulting microemulsions was 2.0 +/- 0.4 nm, and the zeta potential was -45.5 +/- 0.5 mV. Compared to Taxol, the oral bioavailability of paclitaxel SMEDDS increased by 28.6% to 52.7% at various doses. There was a significant improvement in area under the curve (AUC) and time above therapeutic level (0.1 microM) of paclitaxel SMEDDS as compared to those of Taxol following coadministration of both formulations with 40 mg cyclosporin A (CsA)/kg. The oral absorption of paclitaxel SMEDDS slightly enhanced following coadministration of tacrolimus and etoposide, but plasma drug concentrations did not reach the therapeutic level. The nonlinear pharmacokinetic trend was not modified after paclitaxel was formulated in SMEDDS. CONCLUSIONS: The results indicate that SMEDDS is a promising novel formulation to enhance the oral bioavailability of paclitaxel, especially when coadministered with a suitable P-gp inhibitor, such as CsA.     

A Human Physiologically-Based Model for Glycyrrhzic Acid,A Compound Subject to Presystemic Metabolism and Enterohepatic Cycling

Purpose. To analyze the role of the kinetics of glycyrrhizic acid (GD) in its toxicity. A physiologically-based pharmacokinetic (PBPK) model that has been developed for humans. Methods. The kinetics of GD, which is absorbed as glycyrrhetic acid (GA), were described by a human PBPK model, which is based on a rat model. After rat to human extrapolation, the model was validated on plasma concentration data after ingestion of GA and GD solutions or licorice confectionery, and an additional data derived from the literature. Observed interindividual variability in kinetics was quantified by deriving an optimal set of parameters for each individual. Results. The a-priori defined model successfully forecasted GA kinetics in humans, which is characterized by a second absorption peak in the terminal elimination phase. This peak is subscribed to enterohepatic cycling of GA metabolites. The optimized model explained most of the interindividual variance, observed in the clinical study, and adequately described data from the literature. Conclusions. Preclinical information on GD kinetics could be incorporated in the human PBPK model. Model simulations demonstrate that especially in subjects with prolonged gastrointestinal residence times, GA may accumulate after repeated licorice consumption, thus increasing the health risk of this specific subgroup of individuals.     

超声波介导的药物转运系统

目的了解超声波介导的药物靶向转运的研究情况。方法通过查阅和分析近年来国外超声波介导的药物转运文献。结果在超声波的作用下,药物能在体内特定部位释放药物,提高药物的局部浓度,以及治疗基因在细胞内的表达,亦增加药物的经皮渗透量。结论超声波具有良好的促进药物经皮吸收和靶向转运作用,具有一定的研究和应用前景。     

Iontophoresis to Overcome the Challenge of Nail Permeation: Considerations and Optimizations for Successful Ungual Drug Delivery

The AAPS Journal - Vedolizumab immunogenicity has been assessed using an enzyme-linked immunosorbent assay (ELISA) with a ~?0.5 μg/mL drug interference, which may underestimate...     

Employing Drug Delivery Strategies to Overcome Challenges Using TLR7/8 Agonists for Cancer Immunotherapy

Quantitative Systems Toxicology (QST) models, recapitulating pharmacokinetics and mechanism of action together with the organic response at multiple levels of biological organization, can provide predictions on the magnitude of injury and recovery dynamics to support study design and decision-making during drug development. Here, we highlight the application of QST models to predict toxicities of cancer treatments, such as cytopenia(s) and gastrointestinal adverse effects, where narrow therapeutic indexes need to be actively managed. The importance of bifurcation analysis is demonstrated in QST models of hematologic toxicity to understand how different regions of the parameter space generate different behaviors following cancer treatment, which results in asymptotically stable predictions, yet highly irregular for specific schedules, or oscillating predictions of blood cell levels. In addition, an agent-based model of the intestinal crypt was used to simulate how the spatial location of the injury within the crypt affects the villus disruption severity. We discuss the value of QST modeling approaches to support drug development and how they align with technological advances impacting trial design including patient selection, dose/regimen selection, and ultimately patient safety.

     

Intranasal Delivery—Modification of Drug Metabolism and Brain Disposition

Intranasal route continues to be one of the main focuses of drug delivery research. Although it is generally perceived that the nasal route could avoid the first-pass metabolism in liver and gastrointestinal tract, the role of metabolic conversions in systemic and brain-targeted deliveries of the parent compounds and their metabolites should not be underestimated. In this commentary, metabolite formations after intranasal and other routes of administration are compared. Also, the disposition of metabolites in plasma and brain after nasal administrations of parent drugs, prodrugs and preformed metabolites will be discussed. The importance and implications of metabolism for future nasal drug development are highlighted.     

口腔粘膜粘附给药系统

本文对口腔粘膜粘附给药系统这一新型给药系统从口腔粘膜的结构与分类、粘膜粘附的理论及影响因素、处方的设计、剂型、质量评价等方面作了介绍。     

前药--一种可靠的口服结肠靶向释药系统

综述了近年来前药的发展状况，并评价了各类前药的特点和发展前景。前药技术作为一种可靠的口服结肠靶向释药系统，不仅能减少药物的口服剂量，降低副作用并且增加了药效。     

Oral Dispersible System: A New Approach in Drug Delivery System

Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.