Xenon

INDICATIONS AND USAGE: Inhalation of Xenon Xe 133 Gas has proved valuable for the evaluation of pulmonary function and for imaging the lungs. It may also be applied to assessment of cerebral flow.

DOSAGE AND ADMINISTRATION: Xenon Xe 133 Gas is administered by inhalation from closed respirator systems or spirometers. The suggested activity range employed for inhalation by the average adult patient (70 kg) is: Pulmonary function including imaging: 74-1110 MBq (2-30 mCi) in 3 liters of air. Cerebral blood flow: 370-1110 MBq (10-30 mCi) in 3 liters of air. The patient dose should be measured by a suitable radioactivity calibration system immediately prior to administration. RADIATION DOSIMETRY The estimated absorbed radiation doses 2 to an average patient (70 kg) for pulmonary perfusion and cerebral blood flow studies from a maximum dose of 1110 MBq (30 mCi) of Xenon Xe 133 in 3 liters of air are shown in Table 4. Table 4. Radiation Doses Effective Whole Half-Time Lungs* Brain Body *99% of activity is in lungs. 2 Method of Calculation: A Schema for Absorbed-Dose Calculation for Biologically Distributed Radionuclides, Supplement No. 1, MIRD pamphlet No. 1, J. Nucl. Med., p.7 (1968). mGy/1110 MBq (rads/30 mCi) Pulmonary Perfusion 2 min. 2.5(0.25) 0.014(0.0014) 0.027(0.0027) Cerebral Blood Flow 5 min. 6.3(0.63) 0.035(0.0035) 0.068(0.0068)

CONTRAINDICATIONS: None known.

ADVERSE REACTIONS: Adverse reactions related to the use of this agent have not been reported to date.

DESCRIPTION: Xenon Xe 133 Gas is supplied in a mixture of xenon gas (5%) in carbon dioxide (95%). It is contained within septum sealed glass vials and is suitable for inhalation in the diagnostic evaluation of pulmonary function and imaging, as well as assessment of cerebral blood flow. Xenon Xe 133 Gas is reactor-produced as a by-product of Uranium U235 fission. Each vial contains the labeled amount of Xenon Xe 133 radioactivity at the time of calibration. The contents of the vial are in gaseous form, contain no preservatives, and are ready for use. Xenon Xe 133 is chemically and physiologically related to elemental Xenon, a non-radioactive monoatomic gas which is physiologically inert except for anesthetic properties at high doses. PHYSICAL CHARACTERISTICS Xenon Xe 133 decays by beta and gamma emissions with a half-life of 5.245 days. 1 Significant radiations which are emitted by the nuclide are listed in Table 1. Table 1. Principal Radiation Emission Data from Xenon-133 Radiation Mean Energy (KeV) Mean % per Disintegration 1 Kocher, David C., "Radioactive Decay Data Tables," DOE/TIC-11026, p. 138, 1981. Beta-2 100.6 99.3 Ce-K-2 45.0 53.3 Ce-L-2 75.3 8.1 Ce-M-2 79.8 1.7 Gamma-2 81.0 36.5 K α2 X-ray 30.6 13.6 K α1 X-ray 31.0 25.3 K β X-ray 35.0 9.1 EXTERNAL RADIATION The specific gamma ray constant for Xenon Xe 133 is 3.6 microcoulombs/Kg-MBq-hr (0.51R/hr-mCi) at 1 cm. The first half value thickness of lead is 0.0035 cm. A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from the interposition of various thicknesses of Pb is shown in Table 2. For example, the use of 0.20 cm of Pb will decrease the external radiation exposure by a factor of 1,000. Table 2. Radiation Attenuation by Lead Shielding cm of Pb Radiation Attenuation Factor 0.0035 0.5 0.037 10 -1 0.12 10 -2 0.20 10 -3 0.29 10 -4 To correct for physical decay of this radionuclide, the fractions that remain at selected time intervals after the time of calibration are shown in Table 3. Table 3. Xenon Xe 133 Physical Decay Chart (Half Life 5.245 days) Fraction Fraction Day Remaining Day Remaining *Calibration Day 0* 1.000 8 .349 1 .877 9 .302 2 .768 10 .268 3 .674 11 .235 4 .591 12 .206 5 .518 13 .181 6 .452 14 .157 7 .398

HOW SUPPLIED: The Xenon Xe 133 Gas is supplied as part of the CalidoseTM system, consisting of 3ml unit dose vials and the CalidoseTM dispenser for shielded dispensing. Normally vials containing either 370 or 740MBq (10 or 20mCi)/vial, packed 1 vial or 5 vials per shield tube, are supplied. The NDC number for: 10mCi vial is 11994-127; 20mCi vial is 11994-128. Store at room temperature. This radiopharmaceutical is approved for distribution to persons licensed pursuant to the Code of Massachusetts Regulations 105 CMR 120.100 for the uses listed in 105 CMR 120. 547 or 120.552 or under equivalent regulations of the U.S. Nuclear Regulatory Commission, an Agreement State, or a Licensing State. The contents of the vial are radioactive. Adequate shielding and handling precautions must be maintained. Lantheus Medical Imaging, Inc. 331 Treble Cove Rd., N. Billerica, MA 01862 USA For Ordering Tel. Toll Free 800-299-3431 (For Massachusetts & International, Call 978-667-9531) All Other Business 800-362-2668 Patent: http://www.lantheus.com/patents/index.html Printed in U.S.A. 515083-0719 July 2019