Detection of Graft Versus Host Disease With [18F]F-AraG

This single-center imaging study will enroll three cohorts of participants: healthy
volunteers, patients highly suspected to have acute GVHD (aGVHD) and requiring systemic
therapy, and patients at high risk for developing GVHD.

A total of 5 healthy volunteers will undergo [18F]F-AraG PET scans and blood sampling to
better understand [18F]F-AraG biodistribution and stability in the body.

A total of 10 highly suspected acute GVHD patients will be scanned following biopsy taken to
confirm aGVHD. The staging and grading of the disease using the Glucksberg grade and
International Bone Marrow Transplant Registry Severity Index (IBMTR) at time of enrollment
will be noted. Biopsy tissues of consented patients will be analyzed further for T cell
involvement.

A total of 15 high-risk patients (recipients of myeloablative or reduced intensity allogeneic
transplants using either bone marrow or peripheral blood stem cells from HLA-matched or
HLA-mismatched related or unrelated donors-protocols 9142, 9022, 9924) will be recruited. All
those that consent will undergo a PET-CT scan with [18F]FAraG on day 4 +/- 2 days post
transplant. Additionally, these patients will be scanned again between day 14-21 post
transplant. Follow up on these patients will note those that go on to develop aGVHD and the
clinical end point will be correlated to the scans to verify the predictive potential of the
radiotracer.

Inclusion Criteria:

1. Must be 21 years of age or older.

2. Must understand and voluntarily have signed an Informed Consent after its contents
have been fully explained.

1. For patients highly suspected to have aGVHD and requiring systemic therapy,
informed consent should be signed after biopsy taken to support clinical
diagnosis.

2. For patients at high risk for developing aGVHD, informed consent should be signed
prior to transplant.

3. For healthy volunteers only: Must have no known medical problems that would make
undergoing the scan hazardous to the health of the patient or interfere with the
results. In particular subjects should not have any cardiac or immunological disorders
as these would likely affect the scan results. Subjects should have had a full
physical exam within 6 months of the study. If healthy volunteers have not had a full
medical exam within 6 months of the study, one of the nuclear medicine physicians will
conduct the medical exam prior to any study procedures.

4. For patients highly suspected to have aGVHD and requiring systemic therapy only:
Taking steroid treatment for suspected aGVHD for 3 days or less.

5. For patients at high risk for developing aGVHD only: Recipients of myeloablative or
reduced intensity allogeneic transplants using either bone marrow or peripheral blood
stem cells from HLA-matched or HLA-mismatched related or unrelated donors (protocols
9142, 9022, 9924) who have not yet been placed on any therapy for acute GVHD.

Exclusion Criteria:

1. Pregnant or nursing

2. Individuals with known or suspected substance abuse, obtained by self-reporting.

3. Uncontrolled infection

4. Relapsed/persistent malignancy

5. Currently receiving immunotherapy