Advances in GPCR-Targeted PET Radiotracer Patents (2020-2025)

Background: Positron emission tomography (PET) is a molecular imaging technique that exploits the β⁺ decay of selected radionuclides to enable non-invasive in vivo investigation of biochemical and physiological processes, including early and subclinical disease alterations. Radiotracers are designed to bind specific molecular targets with high affinity and selectivity. Among the targets to which PET devotes increasing attention are G protein-coupled receptors (GPCRs)-the largest class of transmembrane receptors-which orchestrate a wide spectrum of biological outcomes and are widely implicated in human disease. Objectives: This review analyzes patents published between 2020 and 2025 focusing on GPCR-targeted PET radiotracers, highlighting design strategies, radionuclide selection, and translational perspectives across oncology, central nervous system (CNS) disorders, and inflammatory diseases. Results: Patent activity shows that most GPCR-targeted PET tracers are derived from validated ligands adapted for imaging while preserving affinity and selectivity. Oncology patents mainly favor peptide-based or modular metal-chelator platforms enabling radionuclide flexibility and theranostic extension, whereas CNS tracers rely on drug-like small molecules optimized under strict ADME and blood-brain barrier constraints. Increasing emphasis on non-orthosteric, function-sensitive, and dual-targeting approaches reflects a shift toward interrogating GPCR signaling states, while inflammatory indications remain comparatively underrepresented despite clear biological foundations. Conclusions: Current patent trends consolidate GPCR-targeted PET tracers as well-established diagnostic tools while progressively expanding their clinical utility, both as platforms supporting translational research-informing mechanistic insight and drug development-and as components of emerging theranostic strategies across multiple disease areas.