PET technology for drug development in psychiatry.

Area of Science:

• Neuroscience
• Pharmacology
• Medical Imaging

Background:

• Positron emission tomography (PET) is a non-invasive in vivo imaging technique.
• PET is crucial for evaluating central nervous system drug target engagement in the human brain.
• Established therapeutic windows exist for dopamine D2 receptor occupancy in antipsychotics (65%-80%) and serotonin transporter (5-HTT) occupancy in antidepressants (70%-80%).

Purpose of the Study:

• To highlight the importance of measuring in vivo target occupancy for drug evaluation.
• To discuss the ongoing development and evaluation of norepinephrine transporter (NET) occupancy for antidepressants.
• To emphasize the need for new PET radioligands for novel drug targets in conditions like schizophrenia and treatment-resistant depression.

Main Methods:

• Utilizes Positron Emission Tomography (PET) imaging.
• Measures in vivo molecular targets, such as dopamine D2 receptors and serotonin transporters (5-HTT).
• Focuses on receptor occupancy as a key metric for drug efficacy and safety.

Main Results:

• Dopamine D2 receptor occupancy between 65%-80% is linked to antipsychotic effects without extrapyramidal symptoms.
• Serotonin transporter (5-HTT) occupancy of 70%-80% is considered a clinical threshold for antidepressants.
• Evaluation of norepinephrine transporter (NET) occupancy using PET is an emerging area for antidepressant research.

Conclusions:

• In vivo target occupancy measurement is essential for evaluating drug efficacy and safety.
• Development of novel PET radioligands is critical for advancing drug discovery for complex neurological and psychiatric conditions.
• PET imaging plays a vital role in personalized medicine by guiding therapeutic strategies based on individual target engagement.