Unique Symposium Stimulates Out-of-the-Box Thinking on Therapies
LRI Taskforce Co-Chairman and
NIAMS Scientific Director Peter
Lipsky, MD, moderated
a lively forum, BioDrug
Symposium, that provided
an opportunity to learn
about the hottest new
ideas for lupus treatments.
Six of the country's
leading scientists
presented their proposed
target in a forum chaired by
Dr. Lipsky, who took the role
of Vice President of Research
and Development at BioDrug, a
fictitious biotechnology company.
The presentations emphasized the
importance of reining in tissue
damaging immune responses in lupus.
The following approaches were
championed by the experts.
Replace Inactive Tregs . . . Jeffrey
Bluestone, PhD, of the University
of California-San Francisco Hormone
Research Institute and the NIH
Immune Tolerance Network,
proposed a clinical trial in which
Tregs T lymphocytes that dampen
down the immune response are
taken from lupus patients, grown in
a laboratory, and then reintroduced
into these patients.
Target Interferons
a group of proteins
important in regulating
the immune response . . .
Jacques Banchereau, PhD,
of the Baylor Institute of
Immunology Research,
proposed developing
agents that would block
the formation or action of
interferon-alpha, while Brian L.
Kotzin, MD of the University of
Colorado Health Sciences Center,
proposed blocking another type
of interferon, interferon-gamma.
Focus on B Lymphocytes
immune system cells that mature
into antibody-producing cells . . .
Betty Diamond, MD, of Albert
Einstein College of Medicine,
proposed
administering
potential
treatments
to remove
self-reactive
B lymphocytes
during periods
of disease
remission to
prevent these
cells from
surviving and maturing into cells that
produce self-destructive antibodies.
Andrew C. Chan, MD, PhD, of
Genentech, Inc., proposed combining
rituximab, an engineered antibody
designed to attack certain B cells,
with another antibody to remove the
self-reactive B cells and also to cause
other B cells to self-destruct.
Target Signaling Molecules . . .
Anthony L. DeFranco, PhD, of
the University of California-San
Francisco, proposed developing drugs
enhancing a protein called Syk that
signals antibody production to stop,
thus reining in the production of
self-reactive antibodies.
A panel of "BioDrug" consultants
consisting of Robert B. Jackson of
Deerfield Partners (financial analyst);
David Wofsy, MD, of the University
of California, San Francisco; Lee S.
Simon, MD (FDA representative);
and Ingrid Wickelgren (contributing
correspondent to Science), raised a
number of issues including the need
to bring lupus trials to more rapid
conclusions, and to carefully consider
which subsets of patients would most
likely benefit from the proposed
intervention.
Jeffrey A. Bluestone, PhD, is recognized
internationally as an immunobiologist who
has made a significant contribution toward
understanding of the biological basis for
immune tolerance the blocking of unwanted
immune responses by reprogramming the
body's immune system. Dr. Bluestone, Director
of the Immune Tolerance Network and the
Diabetes Center at UCSF, told conference
participants, "Lupus therapies focus on
dampening down the entire immune system.
With our present understanding of immune
reactions we should be able to tweak parts of
the system without having to sledgehammer it."
Overcoming Barriers to Lupus Drug Development
How can we tell if a medication is
really helping people who suffer from
lupus? How can we measure if the
patient is really improving on a
particular drug? These and other
complex questions were addressed
in a panel discussion, FDA Guidance
Document: Its Role in Lupus Drug
Development.
Lee S. Simon, MD, then Director of the
FDA's Division of Anti-inflammatory,
Analgesic and Ophthalmologic Drug
Products, reported that the FDA's
Guidance Document intended to help
pharmaceutical companies with lupus
clinical trial designs, is now under
internal review.
Because clinical trials in lupus can
take a long time, drug companies
may choose to put their efforts into
other immune disorders where a
speedier answer is possible. Dr. Simon
suggested that one way to overcome
this barrier is the development of
surrogate endpoints, laboratory or
other clinical biomarkers (predictors)
that are reasonably likely to be
associated with clinical benefit to
lupus patients. "Surrogates could be
considered as endpoints for trials to
seek FDA approval, although clinical
benefit would have
to be shown in trials
after approval," Dr. Simon said.
Designing Clinical Trials
David Wofsy, MD, of the University
of California, discussed ethical
concerns about lupus clinical trials.
"In a lupus trial where there are
already approved treatments, a placebo
should be used with close monitoring
in patients who have very well
controlled disease," Dr. Wofsy said.
Dan Wallace, MD, of Cedar
Sinai/UCLA School of Medicine,
provided the practicing clinician's
view on lupus trials, suggesting
that patient enrollment would be
improved by involving qualified
private practitioners in trials.
Panel participant Susan Manzi, MD,
of the University of Pittsburgh School
of Medicine, discussed what clinical
trials should be measuring, including
reduced mortality, reduced disease
activity, and disease or treatment
damage. She also described typical
complications, such as patient flares,
in setting up lupus trials.
Echoing the complexity of developing
drugs for lupus, Jill P. Buyon, MD,
of New York University School of
Medicine emphasized that no one
set of outcomes can be useful for all
lupus trials. Dr. Buyon described her
study demonstrating two surrogate
markers that may be useful predictors
to determine a need for treatments
even before clinical signs of a flare.
Promoting the discovery of surrogate
markers to speed lupus drug
development is a priority for the LRI.
The Lupus Research Institute thanks the
following companies for their support
of the LRI Scientific Conference:
Amgen, Inc., Aspreva Pharmaceuticals Corp.,
Bristol-Myers Squibb Co., IDEC/Genentech,
La Jolla Pharmaceutical Co., Medarex, Inc.,
and Protein Design Labs, Inc.
|