Potential issues associated with the introduction of virtual control groups into non-clinical toxicology studies

Abstract

In recent years, introducing virtual control groups (VCGs) into toxicology studies is increasingly discussed because of the 3Rs and non-human primate (NHP) supply issues. Evaluating toxicology study results using historical control data is not new; however, introducing a VCG means replacing the concurrent control group in a toxicology study with a VCG, thereby reducing the number of animals used by approximately 30%. While it may be possible to conduct a toxicology study of a developmental compound in which the concurrent control group is replaced with a VCG, the scientific appropriateness of introducing a VCG and its regulatory acceptability needs to be considered. Therefore, we identified the following five issues that may arise when implementing a VCG: 1) regulatory requirements, 2) common issues when introducing a VCG, 3) issues related to histopathological examinations when introducing a VCG, 4) statistical analysis when introducing a VCG, and 5) facility monitor (sentinel) animals. Current regulatory guidelines require a concurrent control group for a pivotal toxicology study, whose results, if do not meet the requirements of these guidelines, cannot be used for new drug approval applications. Even if the use of VCGs is justified from animal welfare and scientific points of view, it is critical that the industry work with health authorities to ensure that data from these studies are accepted. The Japan Pharmaceutical Manufacturers Association will continue to hold necessary discussions with key stakeholders to accelerate efficient and effective new drug development pertaining to the use of VCGs.