A drug being developed as a treatment for multiple sclerosis is entering the third and final phase in a series of clinical trials to test its safety and effectiveness. The medication is branded as Mylinax, a nucleoside analog that interferes with the behavior and production of certain white blood cells—especially lymphocytes—that make up part of the immune system, and are thought to be involved in the origin and development of MS.1
"With the initiation of the Phase III program of Mylinax, we are getting closer to realizing our objective to bring the first oral disease-modifying treatment to people with multiple sclerosis," said Ernesto Bertarelli, CEO of Serono, one of two companies developing the drug, in a statement.
A First Oral Drug for MS
The phase III study will involve medical institutions in several countries, according to Serono and co-developer IVAX Corporation. It will be aimed at assessing the effectiveness of the medication in people with relapsing multiple sclerosis. Assessments of clinical relapses, measurements of each patient's progression to disability, and magnetic resonance imaging (MRI) testing will be key aspects of the trial.
"We are very pleased to have reached this important milestone in the development of Mylinax as a novel therapy for multiple sclerosis," said Phillip Frost, MD, chairman and CEO of IVAX, in a statement.
Promising Results So Far
Previous clinical trials using Mylinax in injection form had positive outcomes for patients with multiple sclerosis, Serono and IVAX stated.2,3 In these trials, the drug significantly reduced the development of new brain lesions, as observed in MRI results. Clinical benefits were also observed in the studies.
Serono and IVAX say the Phase III trial of the drug—also known generically as cladribine (KLAD-ruh-been)—is expected to begin sometime in the first quarter of 2005. An expected end date for the study has not been divulged.
How Multiple Sclerosis Strikes
Multiple sclerosis is thought to be an autoimmune disease that targets normal body tissue. It's believed the immune system initiates an abnormal attack on the cells that make myelin in the central nervous system. Myelin is a fatty substance that sheaths nerve endings, protecting them and helping them send and receive electrical impulses.
When myelin is damaged or destroyed, this nerve "communication" is disrupted. Thus, a person with MS experiences varying degrees of neurological impairment, depending on where in the central nervous system myelin has been affected. Another possible cause may be due to common viruses. A persistent viral infection or an immune system abnormality sparked by a transient viral infection may be the culprit, though that hasn't been proven. It's also been suggested that there are certain environmental factors involved in the origins of MS. Higher incidence of the disease is found in the Northern temperate zones of North America and Europe, indicating that some triggering factor in the environment may play a key role.
There is no known cure for MS at this time. However, current medications are available to help patients manage their symptoms.
Estimates are that between 350,000 and 500,000 people in the United States have been diagnosed with MS. The disease is more common in women and in whites compared to other racial groups. Most are diagnosed between the ages of 16 and 60.
1. Lassman H. Recent neuropathological findings in MS—implications for diagnosis and therapy. J Neurol 2004 Sep;251 Suppl 4:IV2-5.
2. Janiec K, Wajgt A, Kondera-Anasz Z. Effect of immunosuppressive cladribine treatment on serum leucocytes system in two-year clinical trial in patients with chronic progressive multiple sclerosis. Med Sci Monit 2001 Jan-Feb;7(1):93-8.
3. Rice GP, Filippi M, Comi G. Cladribine and progressive MS: clinical and MRI outcomes of a multicenter controlled trial. Cladribine MRI Study Group. Neurology 2000 Mar 14;54(5):1145-55.
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.
