For Immediate
Release
Contact: Larry Weisenthal, M.D., Ph.D.
Weisenthal Cancer Group
(714) 596-2100
Clinical Study Results Published at American
Society
of Clinical Oncology (ASCO) Meeting
Larry
Weisenthal, M.D., Ph.D., a medical oncologist and developer of the EGFRx assay explains that the new test relies
upon what he
calls “Whole Cell Profiling” in which living tumor cells are removed
from an
individual cancer patient and exposed in the laboratory to the new
drugs. A
variety of metabolic and apoptotic measurements are then used to
determine if a
specific drug was successful at killing the patient’s cancer
cells. The
whole cell profiling method differs from other tests in that it
assesses the
activity of a drug upon combined effect of all cellular processes,
using
several metabolic and morphologic endpoints. Other tests, such as
those
which identify DNA or RNA sequences or expression of individual
proteins often
examine only one component of a much larger, interactive process.
According
to Dr. Weisenthal, this may explain why EGFRx
whole
cell profiling is the only test to date to demonstrate a statistically
significant association between prospectively reported test results and
patient
survival. Using the EGFRxä assay and the whole cell profiling method,
Dr. Weisenthal’s
group correlated test results, which were obtained by his lab and
reported to
physicians prior to patient treatment, with significantly longer or
shorter
overall patient survival depending upon whether the drug was found to
be effective
or ineffective at killing the patient’s tumor cells in the
laboratory.
Patients prospectively identified by Dr. Weisenthal as favorable
candidates
averaged 485 days of life after treatment with the targeted therapy
drugs. In contrast, patients identified as unfavorable candidates
for the
drugs averaged 75 days survival after receiving the drugs. This
compares
to 76 days average survival among patients identified as unfavorable
candidates
and who did not receive a targeted therapy drug. Survival among
patients
identified by Dr. Weisenthal as unfavorable candidates was therefore
similar
regardless of whether or not they received the targeted drugs.
Comparing
the whole cell profiling approach with other types of tests Dr.
Weisenthal
states, “Over the past few years, researchers have put enormous efforts
into
genetic profiling as a way of predicting patient response to targeted
therapies. However, no gene-based test as been described that can
discriminate
differing levels of anti-tumor activity occurring among different
targeted
therapy drugs. Nor can an available gene-based test identify
situations
in which it is advantageous to combine a targeted drug with other types
of
cancer drugs. So far, only whole profiling has demonstrated this
critical
ability to distinguish between the activities of different targeted
agents [click here
for
example, PDF file]. The reason this is critical is because
there is a
growing array targeted drugs to choose from. Also, most patients
today
are treated not with a targeted therapy drug alone but rather with a
combination of chemotherapy drugs. Therefore, the existing DNA
and RNA
tests do not reflect the way cancer medicine actually is practiced
today.”
Several
new targeted drugs have been introduced during the last few years and
dozens
more are on the horizon. These so-called “smart drugs” focus their
effects on
specific, identifiable processes occurring within cancer cells.
The new
drugs are highly promising in that they sometimes provide benefit to
patients
who have failed traditional therapies. However, they do not work
for
everyone, they often have unwanted side effects, and they are all
extremely
expensive: some cost patients and insurance carriers $5,000 to $7,000
or more
per month of treatment. Patients, physicians, insurance carriers,
and the
FDA are all calling for the discovery of predictive tests that allow
for
rational and cost-effective use of these drugs.
Dr.
Weisenthal believes that his cell profiling approach, which he already
provides
routinely for a number of physicians nationwide, holds the key to
solving some
of the problems confronting a healthcare system that is seeking ways to
best
allocate available resources while accomplishing the critical task of
matching
individual patients with the treatments most likely to benefit
them.
“Not
only is this an important predictive test that is available today”,
says Dr.
Weisenthal, “but it is also a unique tool that can help to identify
newer and
better drugs, evaluate promising drug combinations, and serve as a
‘gold
standard’ correlative model with which to develop new DNA, RNA, and
protein-based tests that better predict for drug activity.”
About
Weisenthal Cancer Group:
Weisenthal Cancer Group is a clinical cancer testing laboratory and
research
facility headquartered in
For
additional information, phone Weisenthal Cancer Group at (714) 596-2100
between
9 A.M. and 5:30 P.M., Pacific time, or
visit www.weisenthal.org.
########### END
###########