Drug Delivery

Course objectives

The objective of the course is to give the participants an insight into fundamental principles for optimisation of drug delivery based on biological, physico-chemical, and pharmaceutical approaches.

General contents and topics

The overall objective of pharmaceutical research is to deliver a drug substance at the biological target site in a therapeutically optimal amount. This encompasses both the relationships between the chemical and physico-chemical characteristics of a drug substance, the pharmaceutical formulation, and the biological response. A basic understanding of the extent to which these factors affect the relative rate and amount of the drug which reaches the target site is of utmost importance in drug research and development.

A low bioavailability may be a result of the specific biological barriers which a drug substance has to pass before reaching the target site, unfavourable chemical or physico-chemical properties, a suboptimal pharmaceutical formulation, or a combination of these factors.

In relation to drug delivery, three basic aspects are in focus, i.e., release of drug from the formulation, transport to and through biological membranes, and biotransformation.

Drug release is a process not only determined by the intrinsic characteristics of the drug substance but also by the formulation and the properties of the biological environment at the site of drug release, e.g. the influence of luminal contents on the dissolution/solubilisation of drug substances after oral administration. A fundamental knowledge of the complex release characteristics in biological environments as well as transport to the target site is of importance in optimisation of drug delivery. An understanding of the structural and dynamic functions of biomembranes, e.g. the interplay between lipid bilayer structure and drug molecules or excipients, specific transports, and efflux mechanisms, may also add to a more rational design of drug substances and pharmaceutical formulations. The future development of advanced drug delivery systems, e.g. polymeric or particulate drug targeting systems is expected to take advantage of the progress in cell biology and membrane biophysics.

The recent development in cell culture models has opened new opportunities for an efficient evaluation of drug permeation through biological membranes. Cell culture models, isolated membranes and in vivo models are important tools in the evaluation of drug bioavailability, a key parameter in drug delivery.

• Biological barriers to drug absorption - an overview: Biomembranes as absorption barriers and biotransformation as a barrier.
• Physico-chemical characteristics of drug substances.
• Chemical approaches in optimisation of drug delivery: Polymeric delivery systems and lipid based delivery systems.
• Methods for evaluation of bioavailability: Dissolution, membrane permeability, and in vivo.
• Bioavailability/bioequivalence - regulatory aspects.

General information

The 5-day course comprises 10 to 15 lectures and demonstrations. Each lecture will be followed by discussions. The participants will be actively involved in the teaching programme.

Duration

29 April to 3 May 2002

Course weight

0.083 STÅ (STÅ = student full-time equivalent) = 4.98 ECTS (European Credit Transfer System).

Course director

Professor Sven Frøkjær, Department of Pharmaceutics at The Royal Danish School of Pharmacy, and
Managing Director Lars Hovgaard, Galenica.

Course fee

Total: DKK 4,900 (including lunch),
of which operating costs amount to: DKK 500.
An additional amount for study materials: DKK 500.

Closing date for application

1 March 2002.

Course capacity

20 participants.

N.B.

Study materials will be handed out. There will be no formal examination, but to complete the course satisfactorily the participants need to take an active part in the course.

Conditions for participation: The course is primarily offered to PhD students who have completed undergraduate courses in pharmaceutics, pharmaceutical chemistry and pharmacology.
The course will only be held in English.