SOUTH SAN FRANCISCO, Calif., July 5 /PRNewswire/ -- ViroLogic,
Inc. (Nasdaq: VLGC) announced today that a new study using its
highly sensitive PhenoSense(TM) HIV drug resistance assay
demonstrates that HIV patient outcomes can be significantly
improved by the presence of enhanced susceptibility, or
"hypersusceptibility," to antiviral drugs. PhenoSense HIV is
the only commercially available drug resistance test able to
detect hypersusceptibility to HIV drugs. The study was
published in the journal AIDS.
"This study is a significant step forward in understanding how
HIV reacts to drugs at varying degrees of susceptibility and
how that affects a patient's clinical response," said Dr. Nancy
Shulman, fellowship program director in the infectious disease
division at the Stanford University School of Medicine and lead
author of the study. "Arming physicians with reliable
information on HIV resistance and susceptibility, including
hypersusceptibility, can help them treat patients more
In the study, researchers retrospectively examined blood
samples taken from 30 treatment-experienced patients. Each
sample's drug susceptibility profile was measured using
PhenoSense HIV, and resistance-related mutations were
identified using a genotypic test. Researchers compared these
data with viral load test results to determine the impact of
hypersusceptibility on patient outcomes.
They found that patients with virus that was hypersusceptible
to non- nucleoside reverse transcriptase inhibitors (NNRTIs), a
class of HIV drugs, and who had no resistance mutations to
these drugs, experienced significantly greater responses to
NNRTI-based therapy over the 24-week study period than those
patients without hypersusceptibility. Patients with
hypersusceptible virus experienced a 20-fold greater reduction
in viral load over those without hypersusceptible virus.
"We have identified a new, clinically relevant marker for HIV
patient management," said Dr. Nicholas Hellmann, study
co-author and ViroLogic's Vice President of Clinical Research.
"After years spent studying HIV drug resistance, we are
beginning to understand the flip-side-hypersusceptibility. The
additional information provided by PhenoSense HIV may help
physicians design even more effective individualized treatment
regimens for their patients."
In addition to providing insight on hypersusceptibility, the
research team also described the unique phenomenon of HIV
"re-sensitization," in which virus that was resistant to
treatment with NNRTIs actually appeared to become susceptible
again. Detection and measurement of re-sensitization may have
important implications for the long-term management of HIV
infection, since it may expand a patient's treatment options,
an important consideration for the 200,000 patients who face
treatment failure due to drug resistance every year.
PhenoSense HIV is a rapid, highly sensitive drug resistance
assay that allows physicians to directly and reliably measure
clinically significant levels of HIV drug resistance and
susceptibility. With this information, physicians can
individualize treatment regimens for their patients to maintain
effective therapy and avoid unnecessary side effects, resulting
in improved outcomes and reduced treatment costs.
Pharmaceutical companies are also using ViroLogic's assay to
develop new drugs to which HIV might be less resistant.
ViroLogic is a biotechnology company advancing the fields of
individualized medicine and pharmacogenomics, helping to make
them realities in healthcare around the world today. The
Company discovers, develops and markets innovative products to
guide and improve treatment of serious viral diseases such as
AIDS and hepatitis. Its leading expertise in virology,
molecular biology, clinical research, engineering, information
systems, and quality assurance has resulted in technology to
assess drug resistance and susceptibility in viruses that cause
these diseases, which affect millions of people worldwide.
The Company's current products are designed to optimize
HIV/AIDS treatment regimens, providing physicians with
important information to help select appropriate drugs for
their patients and leading to better outcomes and reduced
costs. These products are also being used by major
pharmaceutical companies working to develop new and improved
antiviral therapeutics that can be more effective in an
increasingly drug-resistant environment.
Certain statements in this press release are forward-looking,
including statements relating to the performance of the
Company's testing products. These forward-looking statements
are subject to risks and uncertainties and other factors, which
may cause actual results to differ materially from the
anticipated results or other expectations expressed in such
forward-looking statements. These risks and uncertainties
include, but are not limited to, whether PhenoSense(TM) HIV
will achieve market acceptance, whether payers will authorize
reimbursement for our products, whether we will be able to
expand our sales and marketing capabilities, whether we
encounter problems or delays in automating our process, whether
we successfully introduce new products using our PhenoSense(TM)
technology, whether intellectual property underlying our
PhenoSense(TM) technology is adequate, whether we are able to
build brand loyalty, and other risks and uncertainties detailed
from time to time in our reports to the Securities and Exchange
Commission, including our Annual Report on Form 10-K for the
year ended December 31, 2000.
SOURCE ViroLogic Inc.