A PET Imaging Agent (64Cu-DOTA-Pembrolizumab) for Determining Treatment Response Among Patients With Stage IV Non-small Cell Lung Cancer Receiving Pembrolizumab

PRIMARY OBJECTIVES: I. To describe the safety of administering copper Cu 64-DOTA-pembrolizumab (64Cu-DOTA-pembrolizumab) for PET imaging in patients receiving SBRT for NSCLC during pembrolizumab therapy. II. Evaluate 64Cu-DOTA-pembrolizumab maximum standard uptake value (SUVmax) at baseline for oligoprogressive lesion(s) versus (vs) lesions that were not progressing on pembrolizumab therapy. SECONDARY OBJECTIVES: I. Evaluate change in SUVmax in non-progressing lesions given low dose radiation therapy (LDRT). II. Evaluate change in SUVmax on oligoprogressive lesions treated with SBRT. III. Compare change in SUV-max of 64Cu-DOTA-pembrolizumab (64CDP) from baseline to the follow-up scan on non-progressive lesions not given LDRT or SBRT. IV. Evaluate the impact of different quantitative measures of PET avidity (e.g. SUVpeak, SUVmean, lean-body weight-adjusted, relative to average uptake in liver). EXPLORATORY OBJECTIVE: I. To summarize differences in SUVmax pre- and post-SBRT based on tumor location and clinical course for further hypothesis generation. OUTLINE: Patients receive standard of care (SOC) pembrolizumab intravenously (IV) on day 0, followed by 64Cu-DOTA-pembrolizumab IV over 5 minutes on day 1 and PET scan on day 2. Patients then receive SOC SBRT over 3-5 treatment fractions over a 10-12 day period (approximately days 8-18). Patients may also undergo low-dose radiation therapy (LDRT) over 3-5 treatment fractions over this 10-12 day period based on results of first 64CDP PET scan. Patients then receive SOC pembrolizumab IV on day 21 and 42, followed by 64Cu-DOTA-pembrolizumab IV over 5 minutes on day 43 and PET scan on day 44. Patients also undergo a computed tomography (CT) scan on study. After completion of study treatment, patients are followed for 1 year.