A manipulated form of the antibacterial drug, tetracycline, may one day become the newest therapy for multiple sclerosis (MS) in the form of a pill. Tetracycline is an antibiotic that fights bacterial infections in the body.
A New Way to Treat MS?
However, in this case, medical scientists converted the drug into a form that is non-antibacterial, then tested it in a group of mice infected with a disease that is similar to multiple sclerosis (experimental autoimmune encephalitis (EAE)). Their findings were released at Neuroscience 2004, the Society for Neuroscience's 34th Annual Meeting in San Diego in October.1
The study, headed by Dr. David McKenney, a scientist at Paratek Pharmaceuticals, evaluated the non-antibacterial form of tetracycline with a drug known as monocycline, which previous studies have suggested might also be effective at treating MS.2
The study team had already tested the two potential therapies in lab experiments, and found key differences in their activity—research that led to this preclinical trial of the two drugs.
For the first time, the trial suggested that non-antibacterial tetracycline was effective against the experimental model of multiple sclerosis in the rodents when pitted against monocycline.
Can Patients Tolerate Monocycline?
While a previous study of monocycline at the University of Calgary in Canada2 suggested that that drug is also effective against an MS-like disease in mice, McKenney and his team claim monocycline and other broad-spectrum antibiotics can cause many people to experience intolerable side effects. In their study, McKenney and his associates reported that three non-antibacterial tetracycline compounds, each with unique structures, were able to effectively ease limb paralysis in the rodents.
"The clinical research community has long regarded a pill for MS as an ultimate goal, but so far, attempts to develop a safe, feasible, orally available drug candidate have failed," said Stuart Levy, MD, vice chairman and chief scientific officer at Paratek, maker of the non-antibacterial form of tetracycline, and the study's sponsor. "Our team has successfully modified the tetracycline molecule, keeping the core structure that confers anti-MS activity while removing portions of the molecule with antibacterial effects."
"This represents an exciting advance not only for MS, but potentially for many other inflammation-related disease areas," Levy said.
Partek recently entered into an agreement with Serono to develop and market orally-available treatments for multiple sclerosis. This study is one step toward reaching the objectives outlined in that agreement.
"This new, proprietary class of non-antibacterial tetracycline compounds will avoid the negative consequences associated with long-term antibiotic use, and will not further contribute to the development of antibiotic resistance," said Dr. Michael Draper, associate director at Paratek. "We believe that these highly active, orally available compounds will also prove to be well-tolerated for MS, and we are very proud of this accomplishment."
The study investigators are employed by Paratek Pharmaceuticals.
1. McKenney D, Jackson CL, Berniac J et al. A novel non-antibacterial tetracycline that has potential in the treatment of multiple sclerosis. Neuroscience 2004: The 34th Annual Meeting of the Society for Neuroscience. 2004 Oct 23-27. San Diego, CA.
2. Brundula V, Rewcastle NB, Metz LM, Bernard CC, Yong VW. Targeting leukocyte MMPs and transmigration: minocycline as a potential therapy for multiple sclerosis. Brain 2002 Jun;125(Pt 6):1297-308.
John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include coverage of health news for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.
