Introduction At the time their disease is diagnosed, most patients with multiple sclerosis (MS) (about 85%) are found to have relapsing-remitting multiple sclerosis (RRMS). RRMS is characterized by periods of remission, with few symptoms, punctuated by periods of relapse, when symptoms can be debilitating.  Over time, generally over years, patients recover less well from relapses, and accumulate disability.  Eventually, the vast majority of people with RRMS enter a phase where their symptoms gradually get progressively worse, although there may be periods of additional, temporary worsening called “superimposed” relapses.  At this point, the disease is defined as secondary progressive multiple sclerosis (SPMS). A much smaller subset of patients have progressive worsening of symptoms from the onset of their illness without any relapses.  These patients have a form of MS called primary progressive multiple sclerosis (PPMS). In recent years, several studies have suggested that the irreversible disability in MS results from permanent damage to the central nervous system. There has been considerable focus on the loss of the insulating fatty layer, called myelin, in damaged areas, called lesions, which are found in the brain and spinal cord of patients with MS. These lesions are believed to occur as a result of an immune system attack that causes inflammation and tissue destruction. Without myelin, nerve cells cannot send messages well. Recent studies suggest that damage to the myelin is associated with damage to the axons.   Axons are covered by the myelin sheath. They behave like wires and carry messages to and from nerve cells.  If axons are damaged or cut, nerve cells cannot send messages.  Damage to the axons may occur in areas of both new (acute) and old (chronic) inflammation. This pattern of inflammatory damage can be seen early in MS and continue throughout the course of the disease (Trapp, Ransohoff, & Rudick, 1999). Along with damage to the axons, the brain volume may also decrease over time, an effect that is commonly referred to as brain atrophy. Secondary Progressive MS Mobility in MS NARCOMS News Breaking News Ethical Considerations in Clinical Trials The Changing Definition of MS Current Clinical Trials in MS NARCOMS Information Corner Volume 20, Number 3, Fall 2001 MULTIPLE SCLEROSIS QUARTERLY REPORT Secondary Progressive Multiple Sclerosis: Current Treatment Availability and Future Promise Omar A. Khan, MD, Christina Caon, BSc, RN, and Rana Zabad, MD, Multiple Sclerosis Center, Department of Neurology, Wayne State University School of Medicine, Detroit, MI A joint publication of Eastern Paralyzed Veterans Association and the CMSC/North American Research Committee on MS INSIDE: 8 12 21 26 North American Research Committee on MS 1 continued on page 3 Consortium of Multiple Sclerosis Centers 31 17 24