INDIUM IN 111 CHLORIDE solution

INDIUM IN 111 CHLORIDE by

Drug Labeling and Warnings

INDIUM IN 111 CHLORIDE by is a Prescription medication manufactured, distributed, or labeled by Curium US LLC. Drug facts, warnings, and ingredients follow.

Drug Details [pdf]

DESCRIPTION

Indium In 111 Chloride Sterile Solution is indicated for radiolabeling ProstaScint™ preparations used for in vivo diagnostic imaging procedures. It is also indicated for radiolabeling Zevalin™ preparations used for Radioimmunotherapy procedures. It is supplied as a sterile, non-pyrogenic solution of Indium In 111 Chloride in 0.05 molar hydrochloric acid. No carrier has been added to the solution. Each 0.5 milliliter of the solution contains 185 megabequerels (5 millicuries) of Indium In 111 Chloride at time of calibration (specific activity of >1.85 GBq/μg Indium; >50 mCi/μg Indium at this time of calibration). The solution pH is 1.1 to 1.4.

Radionuclidic Purity

Indium In-111 is cyclotron produced by the proton irradiation ((p,2n) reaction) of cadmium Cd-112 enriched target. At time of calibration, it contains not less than 99.925% indium In-111 and, not more than 0.075% indium In-114m and zinc Zn-65 combined. At the time of expiration, it contains not less than 99.85% indium 111 and not more than 0.15% indium In-114m and zinc Zn-65 combined. No carrier has been added.

Radiochemical Purity

At the time of calibration, the Indium In 111 Chloride Sterile Solution contains not less than 95% of the Indium present as ionic In3+.

Chemical Purity

Indium In 111 Chloride Sterile Solution is tested for the following metallic impurities: copper, iron, cadmium, lead, zinc, nickel, and mercury, and contains extremely low levels of these metals. The sum of the individual impurity ratios for the metals listed is not more than 0.60 ppm.

Physical Characteristics

Indium In-111 decays by electron capture to cadmium Cd-111 (stable) with a physical half-life of 67.32 hours (2.81 days) (see Table 2)1. Photons useful for detection and imaging are listed in Table 1.

Table 1. Principal Radiation Emission Data*

Radiation	Mean Percent Per Disintegration	Mean Energy (keV)
* Kocher, David C., "Radioactive Decay Data Tables", DOE/TIC-11026, 115 (1981).
Gamma-2	90.2	171.3
Gamma-3	94.0	245.4

1 From Radiopharmaceutical Internal Dosimetry Information Center, Oak Ridge Associated Universities, Oak Ridge, TN 37831-0117, February 1985.

External Radiation

The exposure rate constant for 37 MBq (1 mCi) of indium In-111 is 8.3 x 10-4 C/kg/hr (3.21 R/hr) at 1 cm. The specific gamma ray constant for indium In-111 is 3.21 R/hr-mCi @ 1 cm1. The first half-value thickness of lead (Pb) is 0.023 cm. A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from interposition of various thicknesses of Pb is shown in Table 2. For example, the use of 0.834 cm of Pb will decrease the external radiation exposure by a factor of about 1000.

• Shield Thickness (Pb) cm: Coefficient of Attenuation
• 0.023: 0.5
• 0.203: 10-1
• 0.513: 10-2
• 0.834: 10-3
• 1.12: 10-4

These estimates of attenuation do not take into consideration the presence of longer-lived contaminants with higher energy photons, namely indium In-114m.

To correct for physical decay of indium In-111, the fractions that remain at selected intervals before and after calibration time are shown in Table 3.

Table 3. Indium In-111 Physical Decay Chart; Half-Life 67.32 hours (2.81 days)

* Calibration time
Hours	Fraction Remaining	Hours	Fraction Remaining
-72	2.10	0*	1.00
-60	1.85	6	0.94
-48	1.64	12	0.88
-36	1.45	24	0.78
-24	1.28	36	0.69
-12	1.13	48	0.61
-6	1.06	72	0.48