Now
In the pipeline for
MS: Lipoic acid
Promising research has led
to a clinical trial testing whether
an oral antioxidant can protect
against tissue injury associated
with optic neuritis, often the first
sign of MS
The Phase II study,
launched by the National MS
Society, should tell us whether
this novel approach can protect
against MS damage
What is lipoic acid, and why use
it to treat MS?
In MS, the immune system
damages and destroys myelin,
In mice, lipoic acid blocks
immune cells from the brain
and reduces damage to
myelin and nerve fibers.
the material that surrounds and
protects nerve fibers in the brain
and spinal cord. Nerve fibers
themselves are damaged as well,
which appears to drive long-term
disability.
“Free radicals” are normal
byproducts of bodily processes,
and may cause tissue injury and
turn on immune attacks in MS.
Lipoic acid is an antioxidant, a
compound that blocks the action
of free radicals.
What does the research
show so far?
Researchers have been studying
the potential of lipoic acid to
“turn off” the immune attack
in mice with the MS-like disease known as experimental
allergic encephalomyelitis or
EAE. Their results show that
lipoic acid blocks migration of
immune cells into the brain, and
reduces damage to both myelin
and nerve fibers. If given before
EAE begins, lipoic acid prevents
the disease from developing.
Journal of Neuroimmunology
2002;131:104–14
Vijayshree Yadav, MD, MCR,
and colleagues at Oregon Health
& Science University in Portland
conducted a small pilot study in
37 people with MS, to ensure
safety and to see how the compound works. Oral lipoic acid
was generally well tolerated (the
most common side effects were
nausea and bad smelling urine),
and it decreased key inflammatory molecules. Multiple Sclerosis 2005;11:159–65
What is being tested in
this new clinical trial?
Dr. Yadav’s team is now
studying lipoic acid in 54
people with optic neuritis, with funding from the
National MS Society. Optic
neuritis, which causes blurring and loss of vision, is
frequently one of the first
symptoms of MS. As with
MS, optic neuritis involves
damage to myelin and to the
optic nerve itself.
Half of the participants
will take oral lipoic acid and
half will take inactive placebo.
The study is measuring the
status of the optic nerve using
vision tests and OCT (optical
coherence tomography, a quick,
non-invasive eye test that can
show nerve fiber damage and
health).
It is easier to track the localized damage of optic neuritis and
to monitor repair than it is in
MS. Dr. Yadav believes that this
proof-of-concept trial will help
determine whether lipoic acid
has potential as a therapy that
can protect people with MS from
nerve fiber damage and resulting
disability.
For more information, visit
clinicaltrials.gov and search
for this study by its identifier,
NCT01294176.
Read more about agents
in the MS pipeline at
nationalMSsociety.org/
clinicaltrials.
