23 Quest Diagnostics abstracts demonstrate scientific leadership with data highlighting effectiveness of newer, more sensitive, less invasive tests to diagnose and monitor hematologic disease LYNDHURST, N.J., Dec. 9 /PRNewswire-FirstCall/ -- Quest Diagnostics
Incorporated (NYSE: DGX), the nation's leading provider of diagnostic testing,
information and services, announced today that it is presenting new data on a
new series of laboratory-developed diagnostic assays for hematologic diseases,
such as leukemia and lymphoma, at the 47th Annual Meeting and Exposition of
the American Society of Hematology (ASH) in Atlanta. The company expects to
introduce the first of these tests later this month. In total, 23 published
Quest Diagnostics abstracts are being presented during the conference, which
runs from December 10-13, 2005. The abstracts and presentations cover topics
including new plasma-based testing, studies involving testing of new
therapeutics, and studies on a range of advances in clinical diagnostics and
monitoring of therapy. The authors include Quest Diagnostics scientists as
well as collaborators from various academic centers, including MD Anderson
Cancer Center.
Overall, the abstracts present data to demonstrate that plasma-based
assays are an effective and less invasive way of diagnosing and monitoring
leukemia and lymphoma patients, compared with the current laboratory
diagnostic methods. Some current tests require patients to undergo painful
procedures, such as bone marrow biopsies, which require extraction of tissue
with a bone-piercing, large-gauge needle. The abstracts also describe
laboratory developed assays that have the potential of evaluating tumor load
in patients with leukemia and lymphoma as well as quantifying the level of a
tumor's "activity" by measuring the phosphorylation of the oncoproteins; these
capabilities are not possible using conventional methods that test cells from
either bone marrow or peripheral blood.
"To summarize, some of these new plasma-based assays provide physicians
with a more accurate and complete picture of what is happening within a
patient's body compared with biopsies, which provide limited information only
about a specific area," said Maher Albitar, M.D., Medical Director for
Hematopathology at Quest Diagnostics. "When the new assays are available,
they will allow oncologists to assess patients more frequently, allowing them
to more closely monitor a patient's progress on therapy and tailor treatment
accordingly."
"We are excited by the breadth of work Dr. Albitar and his team are
performing, as demonstrated by the wealth of data being presented at this
year's ASH meeting," said Surya N. Mohapatra, Ph.D., Chairman and Chief
Executive Officer of Quest Diagnostics. "The new assays have the potential to
provide the physician with more clinically useful information for the
assessment of prognosis, disease progression, and therapeutic success than
current methods, which could enable oncologists to advance the efficacy of
therapies. Based on the body of research presented at ASH, Quest Diagnostics
has the potential to provide new ways to help clinicians better manage their
patients with a new generation of diagnostics to replace some of the current
tests that depend solely on tissue and cells."
In one study, the investigators reported the development of a new plasma-
based assay for patients with chronic myeloid leukemia (CML). This assay
measures a tumor marker, Bcr-Abl fusion protein, quantifies the tumor load and
also detects the level of activation (phosphorylation) of the Bcr-Abl protein
in the plasma. The investigators believe that the level of activation may have
utility in monitoring the clinical behavior and response to therapy [Meeting
Abstract #2006] Measurement of Free Circulating Bcr-Abl Fusion Protein and Its
Phosphorylation in Patients with Chronic Myeloid Leukemia.
In another study, Dr. Albitar and his colleagues presented data
demonstrating the ability of plasma-based testing to detect JAK2 mutations,
especially in the homozygous state. The JAK2 mutation is the most common
genomic abnormality in myeloproliferative diseases involving blood cells
derived from bone marrow (polycythemia vera, essential thrombocythemia, and
myelofibrosis). The investigators reported that patients with homozygous JAK2
mutations, when detected in plasma, indicated more aggressive disease, as
evidenced by shorter survival, than heterozygous patients. Conventional
testing methods using bone marrow or circulating cells cannot distinguish
between the homozygous and heterozygous populations. [Meeting Abstract #2593]
Hemizygous/Homozygous and Heterozygous JAK2 Mutation Detected in Plasma of
Patients with Myeloproliferative Diseases: Correlation with Clinical Behavior.
In another study, the investigators demonstrated that blood plasma testing
was comparable in accuracy to conventional bone marrow testing and more
sensitive than testing cells found in peripheral blood, which is commonly used
for patients with chronic myeloid leukemia (CML). The study showed that
plasma-based testing assessed mutations associated with resistance to therapy,
in this case Gleevec (Imatinib). [Meeting Abstract #4849] Discrepancy in
Detecting Bcr-Abl Kinase Domain Mutations between Cells from Bone Marrow and
Cells from Peripheral Blood, and Greater Concordance between Bone Marrow Cells
and Plasma Free RNA.
A fourth study showed that plasma based testing by PCR was more effective
than conventional testing by PCR using peripheral blood cells in monitoring
both CML patients who responded to therapy using Gleevec (Imatinib) and those
patients whose residual disease was increasing. [Meeting Abstract #2007]
Plasma RNA Is More Reliable Than Peripheral Blood Cells for Monitoring
Molecular Response to Imatinib in Patients with Chronic Myeloid Leukemia.
The investigators also presented several studies involving new laboratory
developed assays based on flow cytometry to measure levels of intracellular
kinase proteins and their activation (phosphorylation). These new assays may
be used by physicians to help guide and determine the efficacy of various
therapeutic approaches, which currently are being investigated in several
ongoing clinical trials. [Meeting Abstract #2769] Differences in Histone
Acetylation Levels in CD34+ Cells between Acute Myeloid Leukemia (AML) and
Myelodysplastic Syndrome (MDS): Correlation between Higher Levels of Histone
2B Acetylation and Survival in AML; [Meeting Abstract #2772] 4E-Binding
Protein 1 (4E-BP1) in CD34+ Cells as Measured by Quantitative Flow Cytometry
Is an Independent Prognostic Factor in Patients with Acute Myeloid Leukemia.
[Meeting Abstract #3526] Novel Quantitative Flow Cytometry-Based Signaling
Assays Reveal a Potential Role for HSP90 Inhibitors in the Treatment of JAK2
Mutant-Positive Diseases. [Meeting Abstract #3426] Measurement of HSP90 and
HSP70 in CD34-Positive Cells: Lower Levels in Myelodysplastic Syndrome Than in
Acute Myeloid Leukemia and Correlation with Clinical Behavior; Phosphorylation
Levels of BCR-ABL, Stat5, and CrkL Proteins in Imatinib-Resistant CML Patients
as Compared to Previously Untreated CML Patients: Implication of Poor Drug
Binding and Activation of Alternate Pathways. Hypomethylation Therapy of
Decitabine in Patients with Myelodysplastic Syndromes (MDS) Induces Apoptosis
and Reduces Proliferation.
Readers may access all 23 of the Quest Diagnostics abstracts online by
visiting the American Society of Hematology website:
http://www.abstracts2view.com/hem_ash05atlanta/index.php
About Quest Diagnostics
Quest Diagnostics is the leading provider of diagnostic testing,
information and services that patients and doctors need to make better
healthcare decisions. The company offers the broadest access to diagnostic
testing services through its national network of laboratories and patient
service centers, and provides interpretive consultation through its extensive
medical and scientific staff. Quest Diagnostics is a pioneer in developing
innovative new diagnostic tests and advanced healthcare information technology
solutions that help improve patient care. Additional company information is
available at: www.questdiagnostics.com.
The statements in this press release which are not historical facts or
information may be forward-looking statements. These forward-looking
statements involve risks and uncertainties that could cause actual results and
outcomes to be materially different. Certain of these risks and uncertainties
may include, but are not limited to, competitive environment, changes in
government regulations, changing relationships with customers, payers,
suppliers and strategic partners and other factors described in the Quest
Diagnostics Incorporated 2004 Form 10-K and subsequent filings.
SOURCE Quest Diagnostics Incorporated
CONTACT: Gary Samuels (Media), +1-201-393-5700, or Laure Park,
(Investors), +1-201-393-5030, both for Quest Diagnostics