Toxicity Testing

MedPharm offers a variety of in vitro toxicity tests for developed formulations, APIs and excipients. These in vitro toxicity screening studies allow for:

  • The use of human derived models; eradicating the false positive and negative results caused by interspecies variation
  • Rapid identification of potentially toxic candidate molecules and formulations; toxicity screening can be carried out at early stages of the development process
  • Reduced need for animal based testing
  • Reduced costs: reducing the necessity of costly animal studies and identifying issues early in development

MedPharm also offers studies using a range of cell types from different tissues and ex vivo skin, for example where a project necessitates the full barrier function of human skin to be assessed. MedPharm’s expert technical team is able to advise on the most suitable cell type for each project.

Cell based in vitro models utilising a range of cell types from different tissues, these can be used to assess a variety of cellular responses to formulations, APIs and excipients including:

•  Cellular toxicity
•  Proliferation
•  Membrane integrity
•  Release of cytokines

Skin equivalent models using Reconstituted Human Epidermis (RHE) that provides a general structure, composition and biochemistry with a close resemblance to human skin. The cell viability and release of biomarkers can be quantified as an indication of corrosive/irritant effects on the skin. Results from these RHE studies are highly reproducible and are fast becoming the industry standard which allows for comparison with formulations of known irritancy. There are a number of cytokines involved in the pathology of irritation; these are quantified to assess the potential of a substance to cause irritation. MedPharm can carry out in vitro skin corrosion studies, using the Human Skin Model Test (OECD test guideline 431) as well as in vitro skin irritation studies using the  Reconstructed Human Epidermis Test Method (OECD test guideline 439).

Importantly, these tests are validated for use and are recognised by the regulatory authorities, offering a complete replacement for animal testing for irritation. In addition, they can be employed at any stage of the development process; minimising the risk of product failure in latter stages of development.

Ex vivo human skin models employ full thickness human skin to assess the effects of APIs, formulations and excipients on the tissue. The use of human skin has a number of benefits; not least that it provides a good translation to clinical situations by taking into account the barrier effects of skin in vivo. This model allows for assessment of a wider variety of chemicals which are not compatible with cell cultures including whole formulations. The EpiDermTM Tissue Model by MatTek Corp is also available to clients. These models are EVCAM validated.