64Cu DOTA-Trastuzumab PET/CT in Studying Patients With Gastric Cancer

PRIMARY OBJECTIVES:

I. To compare tumor uptake of 64Cu-DOTA-trastuzumab (copper Cu 64-DOTA-trastuzumab) in
gastric cancer patients with pathologic evaluation of tumor human epidermal growth factor
receptor 2 (HER2)/neu expression.

II. To compare copper Cu 64-DOTA-trastuzumab-PET-CT scan with standard radiographic imaging
for staging patients with gastric cancer.

OUTLINE:

Patients receive copper Cu 64-DOTA-trastuzumab intravenously (IV) on day 1 and then undergo
PET/CT scan on days 2 or 3.

After completion of study, patients are followed up for 15 days and periodically for up to 6
months.

Inclusion Criteria:

- Patient must have a histologic diagnosis of gastric or gastroesophageal junction
adenocarcinoma

- Two patients must be HER2 3+ by immunohistochemistry (IHC) or fluorescence in situ
hybridization (FISH) positive

- Either the primary tumor or at least one of the metastatic lesions must be >= 2 cm

- Eastern Cooperative Oncology Group (ECOG) performance status of 0-2

- Life expectancy of >= 3 months

- Women of childbearing potential must have a negative serum pregnancy test within 14
days of copper Cu 64-DOTA administrations and must have agreed to use an effective
contraceptive method; women of child-bearing potential and men must agree to use
adequate contraception (hormonal or barrier method of birth control or abstinence)
prior to study entry and for four months following duration of study participation;
should a woman become pregnant or suspect that she is pregnant while participating on
the trial, she should inform her treating physician immediately

- CT/magnetic resonance imaging (MRI) scan must be obtained within 4 weeks prior to
study entry

- Patients must have normal cardiac ejection fraction

- All subjects must have the ability to understand and the willingness to sign a written
informed consent

- All toxicities should recover to grade 0 or 1 prior to day 1

Exclusion Criteria:

- Impaired cardiac function including any one of the following: complete left bundle
branch block or use of a permanent cardiac pacemaker, congenital long QT syndrome,
presence of ventricular tachyarrhythmias, clinically significant resting bradycardia
(< 50 beats per minute), QT interval corrected by Fridericia's formula (QTcF) > 450
msec on screening electrocardiogram (ECG), or right bundle branch block + left
anterior hemiblock (bifascicular block)

- Presence of atrial fibrillation

- Previous history of angina pectoris or acute myocardial infarction (MI) within 6
months

- Congestive heart failure (New York Heart Association functional classification III-IV)

- Uncontrolled hypertension (mmHg > 160 systolic or > 90 diastolic)

- Patients should not have active infections or concurrent neoplastic disease except for
skin cancer

- Patients may not be receiving any other investigational agents

- At the time of enrollment, patients may not have received any biological,
chemotherapy, or radiation therapy

- Patients who may not have received trastuzumab within the prior 6 months for any other
reason

- Patients who are pregnant

- Subjects, who in the opinion of the investigator, may not be able to comply with the
safety monitoring requirements of the study