Study shows connection between drug's presumed mechanism of action and its ability to maintain axonal integrity
June 18, 2003
Source: Teva Neuroscience
Data presented at the European Neurological Society (ENS) meeting this week suggested that therapy with COPAXONE(R) (glatiramer acetate injection) could reverse cerebral axonal injury or brain nerve damage in relapsing-remitting multiple sclerosis (MS).
The study at Wayne State University, Detroit, Mich., used magnetic resonance spectroscopy (MRS) to measure concentrations of N-acetylaspartate (NAA), a demonstrated marker of neuronal integrity or dysfunction. An increase in NAA is associated with recovery of injured nerve cells or neurons in the brain. Preventing or minimizing damage to neurons is critical in reducing long- term disability in MS.
This study looked at the signal intensities of NAA relative to levels of creatine in the brains of relapsing-remitting MS patients before starting, and one year after, therapy with COPAXONE(R). Mean NAA/Cr values were increased after one year in the COPAXONE(R) -treated patients by 10.2 percent (1.95+/-0.22 at baseline vs. 2.15+/-0.15) after one year (p=0.02). In contrast, longitudinal brain MRS scans of patients not taking any treatment showed an average of five to seven percent decline in NAA/Cr values.
"The increase in the NAA/Cr values in both the abnormal as well as the normal appearing white matter areas of the brain seen in COPAXONE(R)-treated patients provides further insight into the ability of COPAXONE(R) to restore nerve function," said Omar Khan, M.D., Associate Professor of Neurology and Director of Experimental Therapeutics/Clinical Research, Multiple Sclerosis Center, Wayne State University, Detroit. "Further study is planned, and patients are expected to be followed with brain MRI/MRS scans annually for up to four years."
NAA levels can indicate whether nerve cells or axons in the brain are recovering, remaining stable, or being damaged. Previous studies have demonstrated that decline in NAA over time in the white matter of patients with relapsing-remitting MS correlates with progression of disability.
This study evaluated 22 patients with relapsing-remitting MS. Eighteen patients underwent combined magnetic resonance imaging (MRI) and MRS scans before starting COPAXONE(R) (glatiramer acetate injection) treatment and annually, thereafter. Four patients with relapsing-remitting MS who chose not to be on any treatment were studied as untreated controls. At the time the results were presented, 14 patients had completed one year of therapy and had received their annual scans. The MRS scans focused on a volume of interest (VOI), centered at corpus callosum and white matter adjacent to the ventricles. This is a commonly studied area of the brain in MRS scans examining MS pathology.
"The results so far in this study show that COPAXONE(R) increases the NAA/Cr values from baseline. We will know more when all of the data are completed," said Dr. Khan. "This is one of the first studies in MS patients providing in-vivo evidence that migration of COPAXONE(R)-specific T-cells into the brain may occur, resulting in reduced inflammation and protection of nerve cells. Furthermore, this study also supports the emerging concept of COPAXONE(R) as a neuroprotective agent in addition to helping to reduce relapses. Further studies are needed."
COPAXONE(R) is indicated for the reduction of the frequency of relapses in relapsing-remitting MS. In controlled clinical trials, the most commonly observed adverse events associated with the use of COPAXONE(R) which occurred at a higher frequency than in placebo treated patients were: injection site reactions, vasodilation, chest pain, asthenia, infection, pain, nausea, arthralgia, anxiety and hypertonia.
COPAXONE(R) (glatiramer acetate injection) is now approved in 42 countries worldwide, including Canada, the U.S., Australia, Israel and all the European countries. In Europe, COPAXONE(R) is marketed by Teva Pharmaceutical Industries Ltd., and Aventis Pharma. In North America, COPAXONE(R) is marketed by Teva Neuroscience.
Teva Pharmaceutical Industries Ltd., headquartered in Israel, is among the top 30 pharmaceutical companies in the world. Close to 90 percent of Teva's sales are in North America and Europe. The company develops, manufactures and markets generic and branded human pharmaceuticals and active pharmaceutical ingredients. Teva's innovative R&D focuses on developing novel drugs for diseases of the central nervous system.
COPAXONE(R) is a registered trademark of Teva Pharmaceutical Industries Ltd.
This release contains forward-looking statements, which express the
current beliefs and expectations of management. Such statements are based
on current expectations and involve a number of known and unknown risks
and uncertainties that could cause Teva's future results, performance or
achievements to differ significantly from the results, performance or achievements
expressed or implied by such forward-looking statements. Important factors
that could cause or contribute to such differences include Teva's ability
to successfully develop and commercialize additional pharmaceutical products,
the introduction of competitive generic products, the impact of competition
from brand-name companies that sell their own generic products or successfully
extend the exclusivity period of their branded products, Teva's ability
to rapidly integrate the operations of acquired businesses, the availability
of product liability coverage in the current insurance market, the impact
of pharmaceutical industry regulation and pending legislation that could
affect the pharmaceutical industry, the difficulty of predicting U.S. Food
and Drug Administration ("FDA") and other regulatory authority approvals,
the regulatory environment and changes in the health policies and structure
of various countries, acceptance and demand for new pharmaceutical products
and new therapies, uncertainties regarding market acceptance of innovative
products newly launched, currently being sold or in development, the impact
of restructuring of clients, reliance on strategic alliances, exposure
to product liability claims, dependence on patent and other protections
for innovative products, fluctuations in currency, exchange and interest
rates, operating results and other factors that are discussed in Teva's
Annual Report on Form 20-F and its other filings with the U.S. Securities
and Exchange Commission ("SEC"). Forward looking statements speak only
as of the date on which they are made, and the Company undertakes no obligation
to update publicly or revise any forward-looking statement, whether as
a result of new information, future developments or otherwise.
Copyright © 2002 Canada NewsWire Ltd