AlloMap Testing Summary
AlloMap testing is a noninvasive method for determining the risk of acute cellular rejection
(ACR) in heart transplant recipients. The test translates the complex signals of the immune
system’s multiple genes and pathways, specifically those associated with heart transplant
ACR, into an objective, actionable score.
AlloMap testing is a safe, convenient and proven new method to significantly improve
heart transplant recipients’ satisfaction. Rather than having an invasive procedure in a
heart catheterization lab, only a simple and quick blood draw is necessary. The blood
sample is sent to the XDx clinical laboratory, a state-of-the-art clinical lab in Brisbane,
where complex gene information is extracted and analyzed. Using the XDx proprietary
algorithm, the information is translated into a single score that distinguishes rejection
from quiescence, or a stable state.
Since January 2005, the XDx laboratory has
provided AlloMap molecular expression testing for
patients with heart transplants. This safe,
convenient and reliable testing process is a
breakthrough in determining the risk of rejection in
patients 15 years or older who have had a heart
transplant more than 2 months ago. AlloMap testing
is being used at many United States transplant
centers as a non-invasive method to monitor heart
transplant patients for rejection. AlloMap testing is
The Advantages of Non-invasive
AlloMap Testing
Until now, doctors monitored for
signs of organ rejection by using
invasive tissue biopsies that collect
samples directly from the heart.
Biopsies are time-consuming and
may be uncomfortable—and they
can involve the added risks of
infection, heart valve damage and
heart puncture.
currently only available in the United States.
Using a simple blood sample, AlloMap testing
detects the absence of rejection of your new heart
by looking at certain genes in your white blood
cells. When these genes turn on or off (called "gene
expression"), your white blood cells respond by
either quieting down or increasing their activities—
which can cause rejection. Based on your AlloMap
test score, your physician can monitor and manage
your progress after your transplant to determine
that you are not rejecting your heart. Click here to
learn about the importance of rejection monitoring.
Presenting a convenient and
effective alternative to biopsies:
AlloMap molecular expression
testing. All you need for AlloMap
testing is a simple blood sample
that can be drawn at your transplant
center. Your doctor will determine if
AlloMap testing is right for you--and
whether it will be used either alone
or in combination with other
diagnostic tools like biopsy. Click
here for more on the AlloMap
testing process.
Why rejection monitoring is important to your new heart
It is very important for you and your doctor to know if your immune system is trying to
reject your heart. Your immune system includes white blood cells that move within your
bloodstream to ensure good health. These cells are always on the lookout for bacteria,
viruses, and other foreign agents that might make you sick.
After a transplant, your white blood cells see your new heart as a foreign object. Rejection
occurs when white blood cells attack your new heart. If rejection continues, it can actually
damage or destroy your new heart.
Visit www.allomap.com, the website dedicated to AlloMap molecular expression testing.
AlloMap Testing Description
A New Noninvasive Method to Identify Patients at
Indications and Special
Considerations
AlloMap molecular expression testing uses a simple AlloMap testing is indicated for use
blood sample to translate the complex signals from in detecting the absence of acute
cellular rejection (ACR) in clinically
multiple immune system genes and pathways
stable cardiac transplant patients
associated with heart transplant rejection into an
who are:
objective, actionable score. AlloMap testing was
≥15 years of age
developed and validated in a prospective, blinded
>2 months post-transplant
and powered study based on samples and clinical
Low Risk for Acute Cellular Rejection
data collected from the multi-center CARGO study.
The AlloMap test is performed at the CLIA-certified
XDx laboratory in South San Francisco, California,
where the test was developed and validated.
The AlloMap test is a 20-gene, real-time, quantitative
Special consideration in interpreting
results should be given to patients
who are:
On corticosteroid dosage of
>20 mg/day of prednisone or
equivalent
polymerase chain reaction (qRT-PCR) assay.
<30 days post-blood
AlloMap testing applies a proprietary mathematical
transfusion
algorithm that combines the gene expression
<21 days post-rejection
values from genes associated with cardiac allograft
therapy
rejection and generates a single clinically
actionable score. Results are reported as an AlloMap score - an integer ranging from 0
to 40.
The AlloMap Report is delivered via fax to the treating physician, who interprets it in light
of the patient’s clinical picture and other test results. After testing, in most circumstances,
XDx bills the patient's insurer directly.
Incorporating AlloMap Testing into Practice
Transplant clinics can include AlloMap testing in a personalized noninvasive management
protocol starting at > 2 months post-transplant. Using AlloMap testing, physicians can
confidently identify patients at very low
risk for acute cellular rejection.
Clinical Usage for ALLOMAP testing
Longitudinal non-invasive surveillance for ACR
Monitoring for ACR while modifying immunosuppressant regimen
Identify patients early post-transplant who belong to a very low risk group for
ACR within the next few months
Alternative to biopsy in patients with access problems
Provide additional information in the management of patients with “mild
rejection” of biopsy or unclear clinical presentation
Negative Predictive Value (NPV)
The negative predictive value is the percent of all negative tests that are truly negative
tests. For example, for scores <34 in patients 1 or more years post-transplant, the NPV is
>99.2%. This means that out of 1000 AlloMap test results with a score <34, AlloMap testing
will correctly identify the patient as not experiencing acute cellular rejection (quiescent) at
least 992 out of 1000 times; AlloMap testing would miss at most 8 out of 1000 rejections.
Interpreting AlloMap Test Results
In conjunction with clinical judgment
and assessment of graft function,
AlloMap testing can reliably identify
those patients who are at very low risk
for ACR. The AlloMap test report
presents the current AlloMap score and
corresponding 95% confidence interval.
The report also plots the AlloMap
scores for tests performed in the prior
12 months. With this information the
physician can assess the patients risk
for ACR longitudinally.
Example of AlloMap test report
Click here to enlarge (PDF format).
The AlloMap Testing Process
From Ordering Tests to Delivering Results
AlloMap molecular expression testing is conducted only at the XDx laboratory in South
San Francisco, California. Transplant centers must draw and prepare the blood sample
according to the specifications outlined in the XDx Laboratory Services Guide and send it
to the XDx laboratory. XDx provides all equipment and supplies and conducts on-site
training for sample preparation.
This diagram illustrates the typical AlloMap testing process. Place your mouse over each
numbered section for more details. After testing is complete, in most circumstances, XDx
bills the patient’s insurer directly. Click here for more information on billing and
reimbursement.
AlloMap testing process
Billing and Reimbursement
XDx Typically Bills Insurers Directly for AlloMap Testing
Consistent with the established billing practice for specialized esoteric tests, XDx can bill
the patient's health insurer directly. In these cases, medical institutions that order AlloMap
testing will not be financially responsible for the test.1
AlloMap testing is priced below the average reimbursement rates for endomyocardial
biopsy.2 Even more importantly, AlloMap testing can offer a clinical advancement to the
physician and patient, as well as an economical solution for the health care system.
Insurers are reimbursing for AlloMap testing ordered for their members.
Working Together to Educate Insurers Not Yet Covering AlloMap Testing
XDx is committed to working with transplant clinics and patients to ensure that AlloMap
tests receive appropriate consideration from the patient’s insurer. Cooperation from both
clinician and patient is sometimes necessary for XDx to secure coverage from the insurer
for the AlloMap test.
XDx shares the concerns of the transplant team in placing an additional financial burden
on the patient. As a result, XDx created a patient advocacy and financial assistance
program that assists both uninsured and underinsured patients for whom AlloMap testing
is ordered. This program assists patients in obtaining the best coverage/reimbursement
for this test from their insurers. Additionally, as part of this program, XDx gives preferred
pricing for the test to payers who remove co-pay or co-insurance requirements for the test.