Chemical Hazard Assessment

It is impossible to avoid the use of non-human (and especially rodent) species in the safety evaluation of chemicals or compounds, even though we know that their response to a foreign compound may not always reflect that of man. A key challenge is to understand the basis of species differences and the relevance of these observations to man. This can be crucial in the interpretation of data from regulatory studies to ensure successful risk assessment and compound registration.

The CXR approach

The standard approach to inter-species extrapolation of adverse effect data is to use an uncertainty factor of 10 between species (i.e. the acceptable exposure in humans is 1/10th the No Observed Adverse Effect Level (NOAEL) in rodents. However, by conducting carefully designed studies to compare directly the effects in human and rodent systems, it is possible to quantify the relationship between the NOAEL in rodents and humans. Replacing the uncertainty factor with a known experimentally measured value, more accurately defines the acceptable exposure level in humans.

CXR Biosciences is ideally placed to assist in this determination since we have technologies ranging from traditional approaches to innovative transgenic models for use in the analysis of preclinical data. In particular, our ability to use in vivo rodent models in association with both rodent and human in vitro models allows us to extrapolate to human and predict in vivo effects with a high level of confidence. Furthermore, by using the molecular technologies at our disposal we can provide mechanistic detail at the molecular level to support arguments about the relevance, or otherwise, of rodent results to the human situation.