Jeanatope

Iso-Tex Diagnostics, Inc.

Jeanatope

FULL PRESCRIBING INFORMATION: CONTENTS*

• JEANATOPE DESCRIPTION
• Iso-Tex Diagnostics, Inc.

FULL PRESCRIBING INFORMATION

R_{x Only}

JEANATOPE DESCRIPTION

Jeanatope 1-125 (Iodinated 1-125 Albumin Injection) is a sterile, nonpyrogenic,

aqueous solution for intravenous use. Each milliliter provides approximately 10

mg protein (normal human serum albumin), 1.6 mg sodium phosphate, 16 mg

sodium biphosphate, not more than 0.4 mg guanidine hydrochloride, sodium

chloride for isotonicity, and 9 mg benzyl alcohol as a preservative. The

stabilizer aceryltryptophanate and sodium caprylate have a concentration of less

than 0.0089M. The pH has been adjusted to 7.2-7.8 with sodium hydroxide or

hydrochloric acid.

Jeanotope I-125 was prepared from the blood that was non-reactive when tested

for hepatitis B surface antigen (HBsAg) and HIV antibody.

Iodine 125 decays by electron capture with a physical half-life of 60.14 days.¹ 

Photons that are useful for detection and imaging studies are listed in Table 1.

External Radiation

The specific gamma ray constant for I-125 is 1.5 R/millicurie-hour at 1 cm. The

first half-value thickness of Pb for I-125 is .002 mm. 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 .02 min of Pb will decrease the external radiation exposure by a factor of

1,000.

Following intravenous injection, radioiodinated serum albumin is uniformly

distributed throughout the intravascular pool within 10 minutes; extravascular

distribution takes place more slowly. Labeled albumin also can be detected in

the lymph and in certain body tissues within 10 minutes after injection, but

maximum distribution of radioactivity throughout the extravascular space does

not occur until two to four days after administration. The time at which

extravascular activity is maximal has been designated as the "equilibrium time."

When this point has been reached, the radioactivity remaining in the

intravascular and extravascular spaces decreases slowly and exponentially in

parallel fashion.

    The administered radioactivity is eliminated almost entirely in the urine, only

about 2 percent of the total dose ultimately appearing in the feces. The biologic

half-life of labeled albumin is dependent upon a number of factors, and

published studies have varied considerably in their reporting of this figure. It

has ranged, in the literature, from below 10 days to over 20 days. One important

factor affecting the biologic half-life is the initial rate of excretion, and this

depends in part on the quality of the labeled albumin. With Jeanatope 1-125 the

biologic half-life in normal individuals has been reported to be approximately 14

days.

Jeanotope I-125 is indicated for use in the determination of total blood and plasma volume.

At present there are no known contraindications to the use of this preparation.

Radiopharmaceuticals should not be administered to patients who are pregnant

or to nursing mothers unless the expected benefit to be gained outweighs

the potential hazards.

Since I-125 is excreted in human milk during lactation, formula-feedings

should be substituted for breast-feedings. 

Ideally, examinations using radiopharmaceuticats, especially those elective in

nature, of a woman of childbearing capability should be performed during the 

first few (approximately 10) days following the onset of menses.

A few instances of hyperpyrexia and aseptic (chemical) meningeal irritation

have been reported with the use of this product in cisternography. This material

is not approved for use in cisternography.

In the use of any radioactive material, care should be taken to insure minimum

radiation exposure to the patient and occupational workers consistent with

proper patient management.

Although the immunological properties of serum albumin are believed to be

virtually unaltered by the iodinated process, there is a theoretical possibility that

allergic reactions may occur in patients receiving additional doses a number of 

weeks after an initial dose.

Radioiodinated serum albumin is administered intravenously. When a

procedure such as a blood volume determination is to be repeated, the total

dosage administered in any one week should not exceed 7.4 megabecquerels

(200 microcuries).

     To minimise the uptake of radioactive iodine by the thyroid, prior

administration of Lugol's Solution (Strong Iodine Solution USP) may be used.

Ten drops of Lugol's Solution three times a daily, beginning at least 24 hours

before administration of Iodinated Serum Albumin I-125 and continuing for one

or two weeks thereafter, is a suitable dose.

      Complete assay data for each vial are provided on the container.

Note: The expiration date given on the container pertains to the biologic

properties of the material and not to the radioactivity label, it is important to

make certain that the radioactivity in the dose at the time of administration is

sufficient for the intended use.

Parenteral drug products should be inspected visually for 

particulate matter and discoloration prior to administration, whenever solution

and container permit.

     Jeanotope (Iodinated I-125 Albumin Injection) may be colorless to very pale

yellow. Solutions with excessive coloration should not be used.

     The patient dose should be measured by a suitable radioactivity calibration

system immediately prior to administration.

Note: A shielded syringe should be used for withdrawing and injecting the 

Iodinated I-125 Albumin.

Total Blood and Plasma Volumes

Dosage may range from .185 to 1.85 megabecquerels (5 to 50 microcuries).

Blood Volume Determination

A. Preparation of Reference Solution

Remove an aliquot of the contents of the vial to be used in the procedure

identical in volume to the dose to be administered to the patient. Prepare a

reference solution using normal saline as a diluent. The recommended dilution

is 1:4000 (Dilution Factor (DF) = 4000). Determine the radioactivity

concentration (net cpm/ml) of the reference solution. Care must be taken to

assure that the reference solution and the blood samples (Step B3) are assayed

using the same geometric configuration.

A. Administration of Dose

1. Inject the dose into a large vein in patient's arm. Measure the residual

radioactivity in the syringe and needle.

2. Destroy the syringe after injecting. Do not attempt to resterilize.

CAUTION: the syringe should be disposed of in accordance with the US

Nuclear Regulatory Commission or Agreement State regulations

pertaining to the disposal of radioactive waste.

3. At 5 and 15 minutes after injecting the dose, withdraw blood samples

from the patient's other arm with a sterile heparinized syringe.

B. Calculation of Blood Volume

1. Take a known aliquot from each blood sample and determine

radioconcentration in net cpm/mL.

2. Plot the 5- and 15-minute sample counts (net cpm/mL) on semilog graph

paper using the average count value of each sample and determine the

radioconcentration at injection time (zero time) by drawing a straight line

through the 15- and 5- minute points to zero time. The x ordinate iof the

graph is the sample withdrawal time and the logarithmic y ordinate is

radioconcentration in net cpm/mL.

3. Calculate the patient's blood volume (in mL) using the following formula:

  Net cpm/mL reference solution      ×  DF = blood volume (in mL)
Net cpm/mL patient's blood sample

Sample Blood Volume Calculations

Volume of blood sample aliquot                              = 1.0 mL

Volume of reference solution aliquot                       = 1.0 mL

Net counts at zero time                                       = 2500

Net counts obtained from reference solution aliquot  = 2725

Serial Blood Volume Determinations

Jeanotope (Iodinated I-125 Albumin Injection) is administered in sufficiently

low dosage to permit repetitions as often as required by clinical circumstances.

It must be remembered that it is always necessary to correct for background

radioactivity remaining in the blood from former determinations. Therefore, for

each determination after the first one, a background blood sample must be taken

just before the iodinated I-125 Albumin is injected.

Background Blood Sample:

1. Prior to injecting Jeanotope I-125, withdraw background blood sample

   from large vein in patient's arm with a sterile heparinized syringe.

2. Leaving needle in a patient's vein, detach syringe containing blood sample.

3. Withdraw Jeanotope I-125 from the vial and administer (see instructions

    under Blood Volume Determination, Administration of Dose).

4. Determine radioconcentration in net cpm/mL of aliquots taken from

    background and postinjection blood samples, and from the reference

    solution.

The radioconcentration (net cpm/mL) per aliquot of the background blood

sample must be subtracted from the radioconcentration per aliquot of the blood

sample obtained after the injection of Iodinated I-125 Albumin. The formula

for calculating each blood volume determination after the first one thus

becomes:

         Net cpm/mL reference solution                       × 400 = blood volume

Net cpm/mL                            Net cpm/mL                             (in mL)
postinjection      minus             background
blood sample                          blood sample

Plasma Volume Determination

The procedure is essentially the same as that for blood volume determination,

except that the blood sample drawn from the patient is centrifuged, the red blood

cells are removed, and net cpm/mL of the plasma is determined. The formula

for calculation of plasma volume, therefore is:

    Net cpm/mL reference solution           ×      400 =  plasma volume
  Net cpm/mL patient's plasma sample                             (in mL)

Radiation Dosimetry

The estimated absorbed radiation doses to an average patient (70 kg) from an

intravenous injection of 1.85 megabecquerels (50 microcuries) of iodinated

I-125 Albumin USP are shown in Table 4.

For doses of 2.775, 5.55, 18.5 and 27.75 megabecquerels (75, 150, 500 and
750 microcuries), the estimated absorbed doses are 1.5, 3, 10 and 15 times the
number of rads given respectively.

Jeanotope (Iodinated I-125 Albumin Injection USP) is available in multiple dose

vials containing the following amounts of activity on the date of calibration: 3.7

megabequerels /10.0 ml (100 microcuries/10.0 ml), 18.5 megabequerels/0.5 ml

(500 microcuries/0.5 ml) and 37.0 megabequerels/1.0 ml (1.0 millicuries/1.0

ml). Complete assay data for each vial is provided on the container.

      The maximum concentration of Iodinated I-125 Injection does not exceed

one millicurie per milliliter at time of calibration.

Store between 2°C - 8°C.

This radiopharmaceutical is licensed by the Texas Department of Health, Bureau of Radiation Control for distribution to persons licensed pursuant

to 41.26 (b) and Appendix 41-C, Group I and Group II, "Texas Regulations for Control of Radiation," or under equivalent licenses of the U.S.

Nuclear Regulatory Commission, an Agreement State, or a Licensing State.

Iso-Tex Diagnostics, Inc.

P.O. Box 909 . Friendswood, Texas 77549 . USA.

Phone: 281-482-1231 . Customer Service: 800-477-4839 . Fax: 281-482-1070