PET Imaging of the Immune System Using Analog Probes

The goal of this proposal is to assess the biodistribution of 18F-Clofarabine, a new tracer developed for use in PET/CT scans. The investigator's hypothesis is this tracer will allow for imaging immune activation in patients with melanoma before and after treatment with immunotherapy. A maximum of 10 subjects are intended to be included in this study. Each subject will undergo a maximum of two 18F-Clofarabine PET/CT scans, with each visit taking up to 4 hours. The first visit will be prior to the first cycle of immunotherapy treatment, and the second scan will take place 2-4 weeks after the immunotherapy treatment has started. Prior to the PET scan an IV line will be placed. Blood pressure, heart rate, blood oxygen and ECG will be obtained. Then the 18F-Clofarabine will be injected and the PET/CT scan acquisition started. After a maximum of 120 min of scanning, subjects will undergo again blood pressure, heart rate, blood oxygen and ECG.

Sex

All

Minimum age

18 Years

Inclusion Criteria:

The following inclusion criteria also apply:

1. Subject must be able to tolerate PET/CT (i.e. not claustrophobic and able to remain supine)
2. Subject must be 18 years or older
3. Participation in a main study of anti-TIM-3

Exclusion Criteria:

* Patients who meet the exclusion criteria are excluded from this study. 1. Pregnancy

  1. Women of childbearing potential will have to undergo a pregnancy test that will be provided free of charge.
  2. Current knowledge indicates no confirmed detrimental effects to a developing fetus of radiation doses below 10,000 mrem. The radiation dose received from the study procedure is very small in comparison, however, the exclusion criteria is in place to minimize any potential for exposure of a fetus.