DOSAGE AND ADMINISTRATION
Radiation Safety -Drug Handling
Amyvid is a radioactive drug
and should be handled with appropriate safety measures to minimize radiation
exposure during administration [see WARNINGS AND PRECAUTIONS]. Use
waterproof gloves and effective shielding, including syringe shields when handling
Amyvid. Radiopharmaceuticals, including Amyvid, should only be used by or under
the control of physicians who are qualified by specific training and experience
in the safe use and handling of radioactive materials, and whose experience and
training have been approved by the appropriate governmental agency authorized
to license the use of radiopharmaceuticals.
Recommended Dosing And
Administration Instructions
The recommended dose for Amyvid
is 370 MBq (10 mCi), maximum 50 μg mass dose, administered as a single
intravenous bolus in a total volume of 10 mL or less. Follow the injection with
an intravenous flush of 0.9% sterile sodium chloride.
- Inspect the radiopharmaceutical dose solution prior to
administration and do not use it if it contains particulate matter or is
discolored.
- Use aseptic technique and radiation shielding to withdraw
Amyvid solution.
- Assay the dose in a suitable dose calibrator prior to
administration.
- Inject Am yvid through a short intravenous catheter
(approximately 1.5 inches or less) to minimize the potential for adsorption of
the drug to the catheter. Portions of the Amyvid dose may adhere to longer
catheters.
Image Acquisition Guidelines
A 10-minute PET image should be
acquired starting 30 to 50 minutes after Amyvid intravenous injection. The
patient should be supine and the head positioned to center the brain, including
the cerebellum, in the PET scanner field of view. Reducing head movement with
tape or other flexible head restraints may be employed. Image reconstruction
should include attenuation correction with resulting transaxial pixel sizes
between 2 and 3 mm.
Image Display And Interpretation
Am yvid images should be
interpreted only by readers who successfully complete a special training
program [see WARNINGS AND PRECAUTIONS]. Training is provided by the
manufacturer using either an in-person tutorial or an electronic process.
The objective of Amyvid image
interpretation is to provide an estimate of the brain β-amyloid neuritic
plaque density, not to make a clinical diagnosis. Image interpretation is
performed independently of a patient's clinical features and relies upon the
recognition of unique image features.
Image Display
Images should be displayed in
the transaxial orientation with access as needed to the sagittal and coronal
planes. In reviewing the images, include all transaxial slices of the brain
using a black-white scale with the maximum intensity of the scale set to the
maximum intensity of all the brain pixels. Initially locate the brain slice
with the highest levels of image contrast (highest radioactivity signals for
Amyvid uptake) and adjust the contrast appropriately. Start image
interpretation by displaying slices sequentially from the bottom of the brain
to the top. Periodically refer to the sagittal and coronal plane image display,
as needed to better define the radioactivity uptake and to ensure that the
entire brain is displayed.
Image Interpretation
Image interpretation is based
upon the distribution of radioactive signal within the brain; clinical
information is not a component of the image assessment [see WARNINGS AND
PRECAUTIONS]. Images are designated as positive or negative by comparing
the radioactivity in cortical gray matter with activity in the adjacent white
matter. This determination is made only in the cerebral cortex; the signal
uptake in the cerebellum does not contribute to the scan interpretation (for
example, a positive scan may show retained cerebellar gray-white contrast even
when the cortical gray-white contrast is lost).
- Negative scans show more radioactivity in white
matter than in gray matter, creating clear gray-white contrast.
- Positive scans show cortical areas with reduction
or loss of the normally distinct gray-white contrast. These scans have one or
more areas with increased cortical gray matter signal which results in reduced
(or absent) gray-white contrast. Specifically, a positive scan will have
either:
- Two or more brain areas (each larger than a single
cortical gyrus) in which there is reduced or absent gray-white contrast. This
is the most common appearance of a positive scan.
or
- One or more areas in which
gray matter radioactivity is intense and clearly exceeds radioactivity in
adjacent white matter.
Some scans may be difficult to
interpret due to image noise, atrophy with a thinned cortical ribbon, or image
blur. For cases in which there is uncertainty as to the location or edge of
gray matter on the PET scan and a co-registered computerized tomography (CT)
image is available (as when the study is done on a PET/CT scanner) the
interpreter should examine the CT image to clarify the relationship of the PET
radioactivity and the gray matter anatomy.
Figures 1, 2, and 3 provide
examples of negative and positive scans. Figure 1 demonstrates varying degrees
of normal gray-white contrast (negative) and examples where gray-white contrast
has been lost (positive). Figure 2 illustrates typical features of a negative
scan, while Figure 3 shows the loss of gray-white contrast in different brain
regions of a positive scan.
Figure 1
Figure 1: Examples of Amyvid
negative scans (top two rows) and positive scans (bottom two rows). Left to right panels show
sagittal, coronal, and transverse PET image slices. Final panel to right shows
enlarged picture of the brain area under the box. The top two arrows are
pointing to normal preserved gray-white contrast with the cortical
radioactivity less than the adjacent white matter. The bottom two arrows
indicate areas of decreased gray-white contrast with increased cortical
radioactivity that is comparable to the radioactivity in the adjacent white
matter.
Figure 2
Figure 2: Typical Negative
Scan. Images
are displayed from a negative scan with upper (top) and lower (bottom)
transverse slices both showing good gray-white matter contrast. On the right
side of each slice, dotted lines have been used to illustrate the edge of the
cortical gray matter (outer line) and the gray-white border (inner line). These
dotted lines highlight contrast in uptake between the less intense uptake in
the gray matter and the more intense uptake in the white matter. In addition,
arrows illustrate the following points:
- White matter tracts can be
delineated from the frontal lobe to parietal lobe.
- White matter tracts are clearly
identified throughout the occipital / temporal area.
- Scalloped appearance is seen
with “fingers” of white matter in the frontal cortex.
- Low levels of tracer in scalp
or skull that should be distinguished from gray matter uptake by its shape and
position.
Figure 3
Figure 3: Typical Positive
Scan: Images from a positive scan showing upper
(top) and lower (bottom) transverse slices with loss of gray-white matter
contrast in multiple brain regions. On the right side of each slice the edge of
the cortical gray matter has been illustrated with a dotted line. Compared to
the images from the negative case in Figure 2, the gray matter uptake is more
similar to the white matter uptake and the gray-white matter border is more
difficult to discern. In addition, arrows show the following points:
- White matter tracts are
difficult to fully identify as they travel from frontal to parietal lobe.
- Borders of white matter tracts
in occipital / temporal area are lost in places.
- Gray matter in medial parietal cortex (precuneus) has
increased uptake.
- Low levels of tracer in scalp or skull that should be
distinguished from gray matter uptake by its shape and position.
Radiation Dosimetry
The estimated radiation absorbed doses for adults from
intravenous injection of Amyvid are shown in Table 1.
Table 1: Estimated Radiation Absorbed Dose, Amyvid
(Florbetapir F 18 Injection)
ORGAN/TISSUE |
MEAN ABSORBED DOSE PER UNIT ADMINISTERED ACTIVITY (µGy/MBq) |
Adrenal |
14 |
Bone -Osteogenic Cells |
28 |
Bone -Red Marrow |
14 |
Brain |
10 |
Breasts |
6 |
Gallbladder Wall |
143 |
GIa -Lower Large Intestine Wall |
28 |
GI -Small Intestine |
66 |
GI -Stomach Wall |
12 |
GI -Upper Large Intestine Wall |
74 |
Heart Wall |
13 |
Kidneys |
14 |
Liver |
64 |
Lungs |
9 |
Muscle |
9 |
Ovaries |
18 |
Pancreas |
14 |
Skin |
6 |
Spleen |
9 |
Testes |
7 |
Thymus |
7 |
Thyroid |
7 |
Urinary Bladder Wall |
27 |
Uterus |
16 |
Total Body |
12 |
Effective Dose (μSv/MBq)b |
19 |
aGastrointestinal
bAssumed radiation weighting factor, w r, (formerly defined as
quality factor, Q) of 1 for conversion of absorbed dose (Gray or rads) to dose
equivalent (Sieverts or rem) for F 18. To obtain radiation absorbed dose in
rad/mCi from above table, multiply the dose in
μGy/MBq by 0.0037, (e.g., 14 μGy/MBq x 0.0037 = 0.0518 rad/mCi) |
The effective dose resulting
from a 370 MBq (10 mCi) dose of Am yvid is 7.0 mSv in an adult, (19 x 370 =
7030 μSv = 7.030 mSv). The use of a CT scan to calculate attenuation
correction for reconstruction of Amyvid images (as done in PET/CT imaging) will
add radiation exposure. Diagnostic head CT scans using helical scanners
administer an average of 2.2 ± 1.3 mSv effective dose (CRCPD Publication
E-07-2, 2007). The actual radiation dose is operator and scanner dependent. The
total radiation exposure from Amyvid administration and subsequent scan on a
PET/CT scanner is estimated to be 9 mSv.
HOW SUPPLIED
Dosage Forms And Strengths
Amyvid (Florbetapir F 18
Injection) is available in a 10 mL, 30 mL, and 50 mL multidose vial containing
a clear, colorless solution at a strength of 500-1900 MBq/mL (13.5-51
mCi/mL) florbetapir F 18 at End of Synthesis (EOS).
Amyvid is supplied in 10 mL, 30
mL, or 50 mL vials containing 10 mL, 10-30 mL, or 10-50 mL, respectively, of a
clear, colorless solution at a strength of 500 -1900 MBq/mL (13.5 -51 mCi/mL)
florbetapir F 18 at EOS. Each vial contains multiple doses and is enclosed in a
shielded container to minimize external radiation exposure.
10 mL |
NDC 0002-1200-10 (IC1200) |
30 mL |
NDC 0002-1200-30 (IC1200) |
50 mL |
NDC 0002-1200-50 (IC1200) |
Storage And Handling
Store Amyvid at 25°C (77°F);
excursions permitted to 15°C to 30°C (59°F to 86°F) [see USP Controlled Room
Temperature]. The product does not contain a preservative. Store Amyvid
within the original container or equivalent radiation shielding. Amyvid must
not be diluted.
This preparation is approved
for use by persons under license by the Nuclear Regulatory Commission or the
relevant regulatory authority of an Agreement State.
Marketed by Lilly USA, LLC, Indianapolis, IN 46285, USA. Revised: Dec 2013