[18F]F-AraG/Total Body PET Imaging and Healthy Subjects and Lung Cancer Patients

\[18F\]F-AraG, a fluorine-18 labeled analog of an FDA approved drug (Nelarabine) is a new imaging tracer targeted at imaging activated T-cells. Given that immunotherapeutic strategies, in particular immune checkpoint antibodies, focus on the generation of T-cell-based antitumor immunity, uptake of \[18F\]F-AraG within the tumor is hypothesized to correlate with T-cell mediated immune response seen in the biopsy samples of cancer patients treated with immune checkpoint blockade. Correlation of pre- and post-treatment intratumoral immune infiltration by means of PET imaging will guide the development of future clinical trials investigating the role of \[18F\]F-AraG in the monitoring of anti-tumor immune responses. Therefore, proper quantification of \[18F\]F-AraG uptake in tumor lesions, and understanding its relation with physiologic uptake in background tissues is important. Note: checkpoint therapy in this study is standard-of-care and is not under investigation. Available PET/CT scanners can obtain dynamic images only on a portion of the body as large as their axial field of view, generally anywhere between 15-30 cm. The 194 cm long uEXPLORER total-body PET scanner is the world's first device to offer the ability to tomographically image all parts of the body simultaneously. Thus, the uEXPLORER PET/CT (now commercially available and with FDA 510(k) clearance) is the only scanner in the world capable of acquiring total-body dynamic images. In this pilot study, 2-4 healthy volunteers will undergo \[18F\]F-AraG dynamic imaging on the uEXPLORER total body PET/CT scanner to obtain preliminary data regarding pharmacokinetics and early biodistribution images. In addition, 2-4 patients with NSCLC and planned for standard-of-care PD-1/PD-L1 immunotherapy will undergo \[18F\]F-AraG dynamic imaging similarly on the uEXPLORER total body PET/CT scanner to obtain data regarding pharmacokinetics of the tracer in tumor lesions in the context of normal tissue uptake. An optional second similar scan will be performed 7-14 days after the first dose of immunotherapy to explore and document any treatment related changes in \[18F\]F-AraG uptake and kinetics. The study and data collected will be important to recommend an ideal time to acquire a whole body static scan using conventional and widely available PET/CT scanners for adequate tumor to background contrast and quantification, which in turn, will be essential for further clinical development of \[18F\]F-AraG to aid the monitoring of anti tumor immune responses.