There is increasing interest in the application of biomarkers and surrogate endpoints in healthy volunteer studies.

The main focus in phase I clinical trials has traditionally been assessment of safety and tolerability. However, in recent years there has been a growing interest on the use of biomarkers and surrogate endpoints to provide pivotal information on efficacy, dose-response and time-effects of drugs.

ICON has worked extensively in this area, developing and validating pharmacodynamic models for investigating a range of therapeutic targets, as part of its own research and development efforts and in partnership with Sponsors. These specialist techniques fall broadly into two categories.

PD Models of Disease State

Use of healthy volunteer models has proven to be fast and reliable for determining if a drug has the necessary characteristics to be taken forward into more expensive patient trials. ICON’s Clinical Pharmacodynamics team have developed and validated a variety of pharmacodynamic models in a broad range of therapeutic areas, including:

  • Pain (acute and chronic)
  • Inflammation
  • Appetite/Obesity
  • Anxiety
  • Cognitive function
  • Metabolic function/Diabetes
  • Sexual Dysfunction
  • Imaging
  • Response markers at, or in proximity of, the site of action, incl. cerebrospinal fluid, bone marrow, broncho-epithelial lining, or duodenal lumen, as the asset may require.
  • Drug response after a challenge, e.g. with LPS, antigen exposure, or CO2, as the asset may require

Techniques for Specific PD Responses

When a protocol requires the inclusion of a specific technique that is out of the normal scope of a CPU, the Pharmacodynamics group is responsible for identifying, validating and testing the equipment. ICON offers a wide variety of techniques covering tests for sedation, CNS imaging, physiological assessments and mood assessments.