TRACER applies, as part of its unique optical and nuclear molecular imaging strategy, the so-called microdosing concept, as defined by the FDA / EMA.
Microdosing, is a defined concept for studying the behaviour of tracers and/or therapeutic compounds (drugs) in humans through the administration of doses so low (“sub-therapeutic”) they are unlikely to produce local or a whole-body therapeutic effects, but high enough to allow the cellular response or binding of the tracer or therapeutic compound to be studied. The labelling of the tracer / drug is either performed by GMP fluorescent or nuclear labelling and provides respectively, real-time in vivo and ex vivo tissue distribution data for image-guided surgery, pathology or endoscopy purposes when it concerns fluorescence, or whole-body pharmacokinetic and biodistribution data when it concerns nuclear labelling.
The particular studies are defined as phase 0 studies and conducted before a clinical Phase I to predict whether a drug is viable for the next phase of testing and thus creating early go/no-go decision-making. Human microdosing aims to reduce the amount of testing done on animals, the resources spent on non-viable drugs, and creating earlier go / no-go decision-making in the early phases of clinical development.
In august 2018, the FDA has released the guidance to assist sponsors of microdose studies and the ICH guidance for industry M3(R2).
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