Increasing the use of microphysiological systems (MPS) in Three Rs and regulatory applications is a nuanced but important goal, which would also help increase their scientific impact. There are three distinct and important stakeholder groups that each play a unique role in expediting the use of MPS for regulatory purpose - namely, commercial MPS developers, end-users and regulators. Additionally, non-profit organisations, such as the 3Rs Collaborative (3RsC), can help coordinate these efforts. This paper introduces the MPS Initiative, as organised by the 3RsC, and clarifies the potential for MPS to benefit all Three Rs. Key differences in the use of MPS-derived data for regulatory evidence of efficacy versus safety, and for various other contexts of use, are discussed. Finally, the results are presented from a survey of primarily commercial MPS developers, that collected their views on the realistic responsibilities of each stakeholder group. The results also highlight their key perspectives on the use of MPS, in the context of Three Rs and regulatory applications.
Keywords: 3Rs; complex in vitro models; context of use; in vitro; microphysiological systems; organ on a chip; regulatory science; replacement.