Multiple Sclerosis (MS) is a degenerative disease of the central nervous system that is estimated to affect more than 400,000 Americans. While the exact cause of MS has been widely thought to be a manifestation of some type of autoimmune reaction, current research indicates that, in addition to autoimmunity, several other factors may be involved in the disease process. Such factors include a possible genetic predisposition to MS, exposure to some as yet unknown environmental toxins, and infection with viral organisms.
Current Treatments for MS
Since it is becoming clear that MS can be due to several different pathologies, it should be obvious that no single treatment is likely to work in all patients. Currently, the US Food and Drug Administration has approved six therapeutic agent for the treatment of MS. Of the six, four are considered to be “front line” agents and the remaining two are placed in the “second line.” category.
First-line drug therapies are those agents that are used once the diagnosis of MS has been made and are used to both limit the progression of the disease as well as alleviate symptoms that are currently present. These agents are:
· interferon beta-1b (Betaseron), administered as a once weekly subcutaneous injection
· interferon beta-1a (Avonex), administered as a once weekly intramuscular injection
· interferon beta-1a (Rebif) , administered as a 3-times per week subcutaneous injection
· glatiramer acetate (Copaxone), administered as a once daily subcutaneous injection.
Every first-line agent is known to produce a constellation of side effects which vary from patent to patient. The two most common of these side effects are 1) flu-like symptoms ranging from mild to incapacitating and 2) pain and tissue destruction at injection sites.
Second-line therapies are generally used as “treatments of last resort”. This is because, unlike the interferons or glatiramer acetate, these agents directly suppress the body’s immune system and may limit the body’s ability to protect itself against infection. The approved second line agents are:
· mitoxantrone (Novantrone) administered intravenously
· natalizumab (Tysabri), also administered intravenously
Emerging Treatments for MS
There are several potential pharmaceutical treatments for MS that are in the later stages of clinical trials. These agents include:
· Fingolimod: This agent was initially developed as an anti-rejection drug for use in organ transplant recipients but was proved unsuccessful during clinical trials. A subsequent clinical trial in MS patients not on other therapies demonstrated that fingolimod reduced the accumulation of MS-specific lesions on MRI by 43% to 61% relative to placebo and was associated with clinical improvement in over 50% of those participating in the study.
Fingolimod is currently undergoing extended clinical trials, with the first results due in 2008.
· Fumarate: Fumarate is derived from the plant Fumaria officinalis, which has been used to treat skin diseases such as eczema since at least the 17th century, has been shown to inhibit the immune system. Initial phase 3 trials have shown that fumarate produced 69% reduction in MS-specific lesions on MRI. This initial study did not examine clinical improvements in the study population.
Fumarate is now in extended phase 3 trials.
For More Information
The most reliable online sources for information about MS and treatment strategies is the National Institute of Neurological Diseases and Stroke’s Multiple Sclerosis Information Page.
As always, the information presented above is of an informational nature only and is not a substitute for consultations with your health care provider.
