Dermal

Dermal systems

In recent years there has been an increasing interest in the dermal application of drugs due to the simplicity of this type of delivery system. Despite this positive trend, costly and time-consuming clinical studies must still be performed in order to determine dermatopharmacokinetic parameters. Modern in-vitro studies complement conventional clinical research and now make a significant contribution to the characterization of topically applied drug formulations. Drugs that are topically applied but that act only in deeper lying skin tissue can now be studied using novel test models and modern analytical techniques without the need for extensive and costly clinical investigations. For any new drug preparation it is now possible to determine with in-vitro methods whether the pharmaceutical active ingredient is able to penetrate the skin “barrier”.
In-vitro studies also offer an interesting alternative when optimizing the composition of a formulation to achieve the required drug uptake across the skin, when investigating the interaction of chemicals with the skin, or when developing cosmetic products.

Scopes of application:
  • How to select drug candidates for dermal application?
  • How can the safety of cosmetic active ingredients, excipients and the final products be evaluated for approval procedures?
  • How can I evaluate the safety of industrial chemicals and pesticides?
  • How can the right kind of device be developed and can there be further improvements (e.g. micro needle delivery systems or other physical drug delivery techniques)?
  • How to select a suitable vehicle (formulation base)?
  • How to test drug delivery strategies?
  • How to prepare clinical trials?
  • How to characterize topical dosage forms during retroactive approval?
  • How much can my product be differentiated from that of a competitor?

 

Models

Assays

Human Skin
  • Permeation (Franz diffusion cells)
  • Penetration (“Saarbruecker model” apparatus)
Porcine skin
  • Permeation (Franz diffusion cells)
  • Penetration
  • Influence of the formulation
  • Investigation of enhancing concepts
  • Investigation of transdermal
    systems
Other animal skins (on request)
  • Permeation
Synthetic membrans
  • Release according to SUPAC-SS (Franz diffusion cells)
Bovine hoof membranes
  • Permeation (Franz diffusion cells)
  • Penetration

Across Barriers Skin Bank

Due to the fact that animal skin is different in many properties from the human skin, the transposition of the study results are often not possible. That is the reason why Across Barriers has created its own human Skin Bank, containing a variety of human skins.

 

 

Factsheet "Dermal applications"