Non-invasive radiotracer imaging as a tool for drug development

Area of Science:

• Nuclear medicine
• Radiopharmaceutical chemistry
• Pharmacology

Background:

• Non-Invasive Radiotracer Imaging (NIRI) employs positron-emitting isotopes (e.g., 11C, 18F) for PET or single photon-emitting nuclides (e.g., 123I) for SPECT.
• These techniques provide high-resolution anatomical distribution and localization of radiolabeled drugs in vivo.
• NIRI enables real-time human studies on receptor occupancy and drug off-rate kinetics.

Purpose of the Study:

• To review the utility of NIRI, particularly PET, in pharmaceutical drug development.
• To highlight the potential of imaging advances in developing cancer drugs and gene therapies.
• To provide an overview of novel radiotracer design for emerging therapeutic targets.

Main Methods:

• Radiolabeling potential new drugs (typically with 11C) for direct imaging.
• Indirectly assessing drug efficacy by studying unlabeled drug inhibition of radioligand binding.
• Utilizing imaging to demonstrate drug effects via biochemical markers (e.g., glucose metabolism, blood flow).

Main Results:

• NIRI, especially PET, is increasingly accepted as a crucial tool in pharmaceutical development.
• Demonstrated ability to provide critical information on drug distribution and target engagement in human subjects.
• Successful application in studying drug effects on physiological processes like metabolism and blood flow.

Conclusions:

• NIRI offers unique advantages for in vivo drug assessment in humans.
• Imaging modalities like PET are pivotal for advancing cancer drug and gene therapy development.
• Ongoing development of novel radiotracers will expand NIRI applications for new therapeutic targets.