Showing papers in "Advanced Drug Delivery Reviews in 1997"

TL;DR: Experimental and computational approaches to estimate solubility and permeability in discovery and development settings are described in this article, where the rule of 5 is used to predict poor absorption or permeability when there are more than 5 H-bond donors, 10 Hbond acceptors, and the calculated Log P (CLogP) is greater than 5 (or MlogP > 415).

TL;DR: This chapter is a critical review of biodegradation, biocompatibility and tissue/material interactions, and selected examples of PLA and PLGA microsphere controlled release systems, and emphasis is placed on polymer and microSphere characteristics which modulate the degradation behaviour and the foreign body reaction to the microspheres.

TL;DR: Considering the Noyes-Whitney dissolution model shows that drug diffusivity, solubility in the gastrointestinal contents, the surface area of the solid wetted by the lumenal fluids and the GI hydrodynamics all play a role in determining the in vivo dissolution rate.

TL;DR: A paradigm of analysis and synthesis has allowed us to obtain a better understanding of physiological barriers in solid tumors, and to develop novel strategies to exploit and/or to overcome these barriers for improved cancer detection and treatment.

TL;DR: The microencapsulation process in which the removal of the hydrophobic polymer solvent is achieved by evaporation has been widely reported in recent years for the preparation of microspheres and microcapsules based on biodegradable polymers and copolymers of hydroxy acids.

TL;DR: Self-emulsifying drug delivery systems (SEDDS) are mixtures of oils and surfactants, ideally isotropic, sometimes including cosolvents, which emulsify under conditions of gentle agitation, similar to those which would be encountered in the gastro-intestinal tract as discussed by the authors.

TL;DR: This review attempts to provide a framework for the assessment of lipid based formulations by describing how aspects of GI physiology, and the choice of lipids and their formulation attributes, impact on dose form performance.

TL;DR: Characterization of the roles of CYP3A4 and Pgp in limiting oral drug availability may be aided by recent success in the development of human intestinal cell lines that stably express both CYP-glycoprotein and PGP.

TL;DR: Results indicate that depot formulations of leuprorelin may be potentially useful in the therapy of endocrine diseases in humans and animals.

TL;DR: Both direct biochemical and indirect in vivo clearance data suggest significant inter-individual variability in gut wall CYP3A-dependent metabolism, which may represent an important and highly sensitive site of metabolically-based interactions for orally administered drugs.

TL;DR: Recognising the interactions of drugs with intestinal secretory and metabolic systems that limit absorption will lead to novel strategies of overcoming problems of poor oral bioavailability.

TL;DR: It appears as though intestinal metabolism plays a much greater role in the pharmacokinetics of orally administered drugs than previously thought, and compounds that alter CYP3A4 and/or p-glycoprotein will alter the oral pharmacokinetic of cyclosporine and tacrolimus.

TL;DR: The solubilization of drugs in bile salt micelles is reviewed, methods which can be used for assessment of lipolysis in vitro are described, and preliminary biostudies using formulations optimised for rapidlipolysis are presented.

TL;DR: This manuscript will focus on the physiological limitations for oral peptide delivery and on various strategies using chemical modifications to improve oral bioavailability of peptide-based drugs.

TL;DR: Antibody-directed enzyme prodrug therapy (ADEPT) as mentioned in this paper is a two-step antibody targeting system that has benefits over a one-step chemo-, toxin, or radioimmunoconjugate.

TL;DR: The use of polymer microspheres for single-step immunization is reviewed and future applications for the improvement of vaccines and immunotherapies by utilizing encapsulation technology are discussed.

TL;DR: Liposome localization in tumors appears to be the result of an enhanced rate of extravasation through the abnormally permeable microvasculature of tumors coupled with an impaired lymphatic drainage.

TL;DR: The factors to be considered in developing dry powder inhalers (DPIs), particularly the formulation, metering design and flow path in the device are reviewed.

TL;DR: The principles of chemotherapy using polymer implants and injectable microspheres are reviewed, and recent preclinical and clinical studies of this new technology for treating cancer are summarized.

TL;DR: It is argued that for many tumors the necessary condition for an effective anti-cancer activity of systemically administered liposomal doxorubicin formulation is the long circulation life of liposomes in blood and stable drug encapsulation.

TL;DR: Nanoparticles could prove to be an effective dosage form for an intra-arterial localization of therapeutic agents for preventing restenosis in a clinical setting.

TL;DR: A review of formulations for delivering therapeutic aerosols to the lungs is presented in this paper, with particular emphasis placed on preparing fine powders containing macromolecule drugs, such as peptides and proteins.

TL;DR: Immobilized Artificial Membranes are monolayers of phospholipid analogs covalently bonded to the surface of silica particles that have resulted in IAMs' being useful as a physico-chemical model of drug-membrane partitioning.

TL;DR: This chapter has discussed the use of one such in vitro model, i.e. the Caco-2 cells, in elucidating the roles of the physical and biochemical barriers to drug absorption posed by the intestinal epithelium and illustrated how this improved understanding about the barriers todrug absorption can be used for the design and development of drug candidates with enhanced oral absorption.

TL;DR: The extent of this effect appears to be unpredictable, both with respect to a specific drug as well as a particular individual, and the greatest age-related change in oral bioavailability and plasma concentrations is likely to occur with drugs that exhibit a significant first-pass effect in young subjects.

TL;DR: In vivo gene therapy trials for cancer and cystic fibrosis, have shown promising results both in safety and efficacy and the development of new cationic lipids, and the combination of a cationsic lipid with a neutral lipid has conferred improved efficiency to cationIC lipid-mediated gene transfer.

TL;DR: In this review comparatively little effort will be taken to prove the dominant role of surface energetics in inhalation products; this is primarily because much of the proof which exists is held as confidential by manufacturers.

TL;DR: A therapeutic strategy has been designed to take advantage of GST pi activation of a prodrug, TER 286, which may provide further insight into the action of these agents in the cell as well as prove useful in endeavors to modulate anticancer drug resistance.

TL;DR: In this review, the promotion of intestinal lymphatic drug transport is addressed from two standpoints, namely, prodrug formation and formulation optimisation and common approaches for promoting lymphatic transport are addressed.