Ga-68-DOTATOC

GA-68-DOTATOC- edotreotide gallium ga-68 injection, solution
UIHC – P E T Imaging Center

1 INDICATIONS AND USAGE

Ga 68 DOTATOC Injection is indicated for use with positron emission tomography (PET) for the localization of somatostatin receptor positive neuroendocrine tumors (NETs) in adult and pediatric patients.

2 DOSAGE AND ADMINISTRATION

2.1 Radiation Safety – Drug Handling

Handle Ga 68 DOTATOC Injection with appropriate safety measures to minimize radiation exposure [see Warnings and Precautions (5.1)]. Use waterproof gloves, effective radiation shielding and appropriate safety measures when preparing and handling Ga 68 DOTATOC Injection.

Radiopharmaceuticals should be used by or under the control of physicians who are qualified by specific training and experience in the safe use and handling of radionuclides, and whose experience and training have been approved by the appropriate governmental agency authorized to license the use of radionuclides.

2.2 Recommended Dosage and Administration Instructions

Recommended Dosage

In adults, the recommended amount of radioactivity to be administered for PET imaging is 4 mCi (148 MBq) with a range of 3 mCi to 5 mCi (111 MBq to 185 MBq) administered as an intravenous injection with an injection rate of approximately 10 seconds per mL.

In pediatric patients, the recommended amount of radioactivity to be administered for PET imaging is 0.043 mCi/kg of body weight (1.59 MBq/kg) with a range of 0.3 mCi (11.1 MBq) to 3 mCi (111 MBq) as an intravenous injection with an injection rate of approximately 10 seconds per mL.

Administration

• Use Ga 68 DOTATOC Injection within 3 hours of calibration time.
• Use aseptic technique and radiation shielding when withdrawing and administering Ga 68 DOTATOC Injection.
• Inspect Ga 68 DOTATOC Injection visually for particulate matter and discoloration before administration. Do not use the drug if the solution contains particulate matter or is discolored.
• Calculate the necessary volume to administer based on measured activity, volume, calibration time, and date.
• Measure the patient dose immediately prior to administration in a dose calibrator.
• After injection of Ga 68 DOTATOC Injection, administer an intravenous flush of sodium chloride injection, 0.9% to ensure full delivery of the dose.
• Dispose of any unused drug in a safe manner in compliance with applicable regulations.

2.3 Use with Somatostatin Analogs and Patient Hydration

Somatostatin Analogs

Somatostatin analogs bind to the same somatostatin receptors as Ga 68 DOTATOC

• Discontinue short-acting somatostatin analogs 24 hours before imaging with Ga 68 DOTATOC Injection.
• Image patients with Ga 68 DOTATOC Injection just prior to dosing with long-acting analogs of somatostatin [see Drug Interactions (7)].

Patient Hydration

Instruct patients to drink water to ensure adequate hydration prior to administration of Ga 68 DOTATOC Injection and to continue to drink and void frequently during the first hours following administration to reduce radiation exposure [see Warnings and Precautions (5.1)].

2.4 Image Acquisition

For Ga 68 DOTATOC PET imaging, a whole-body acquisition from the skull vertex to mid-thigh is recommended. Image acquisition can begin at 60 minutes (range 55 to 90 minutes) after the intravenous administration of the Ga 68 DOTATOC Injection. Adapt Ga 68 DOTATOC Injection uptake time and scan duration according to the equipment used, and the patient and tumor characteristics, to obtain the optimal image quality.

2.5 Image Interpretation

Ga 68 DOTATOC binds to somatostatin receptors. Based upon the intensity of the signals, PET images obtained using Ga 68 DOTATOC Injection indicate the presence and density of somatostatin receptors in tissues, .Uptake can also be seen in a variety of non-NET tumors that contain somatostatin receptors or as a normal physiologic variant [see Warnings and Precautions (5.2)]. NET tumors that do not bear somatostatin receptors will not be visualized.

2.6 Radiation Dosimetry

Estimated radiation absorbed doses per injected activity for organs and tissues of adult patients following an intravenous bolus of Ga 68 DOTATOC Injection are shown in Table 1. Estimated radiation effective doses per injected activity for adult and pediatric patients following an intravenous bolus administration of Ga 68 DOTATOC Injection are shown in Table 2.

Table 1: Estimated Radiation Absorbed Dose per Injected Activity in Selected Organs with Ga 68 DOTATOC

Site	Absorbed Dose (mGy/MBq)
Urinary bladder wall	0.119 ± 0.058
Spleen	0.108 ± 0.065
Kidney	0.082 ± 0.020
Adrenal gland	0.077 ± 0.028
Liver	0.041 ± 0.014
Red marrow	0.016 ± 0.003
Gallbladder wall	0.015 ± 0.001
Total body	0.014 ± 0.002
Lungs	0.007 ± 0.001
Effective dose (mSv/MBq)	0.021 ± 0.003

The effective radiation dose resulting from the administration of 148 MBq (4 mCi) to an adult weighing 75 kg, is about 3.11 mSv. For an administered activity of 148 MBq (4 mCi) the typical radiation dose to the critical organs, which are the urinary bladder wall, the spleen and the kidneys/adrenals, are about 18 mSv, 16 mSv and 12 mSv, respectively. Because the spleen has one of the highest physiological uptakes, higher uptake and radiation dose to other organs or pathologic tissues may occur in patients with splenectomy.

Table 2: Estimated Radiation Effective Dose per Injected Activity after a Ga-68 DOTATOC Injection

Age	Model Weight (kg)	Effective Dose per Injection Activity (mSv/MBq)
Adult	73.7	0.019
15 years	56.8	0.026
10 years	33.2	0.041
5 years	19.8	0.066
1 year	9.7	0.13
Newborn	3.6	0.36