Multiple sclerosis (MS) is a neurological disease in which myelin — the protective fatty layer surrounding nerves — becomes damaged. This can negatively impact normal nerve function and cause a variety of symptoms, such as numbness or tingling, vision problems, mobility problems, weakness, cognitive dysfunction, and more.
Not all forms of MS are the same. The majority of patients who develop MS begin with a relapsing form of the disease that features acute neurological attacks and a waxing and waning of symptoms. Approximately 10 to 15 percent of patients who develop MS have a progressive form of the disease from the beginning that features steady worsening of neurological function with occasional plateaus or minor improvements. A number of patients with relapsing-remitting MS (RRMS) go on to develop the secondary progressive MS (SPMS) form of the disease.
Primary progressive multiple sclerosis (PPMS) can be more challenging to diagnose and is definitely harder to treat than relapsing MS. Since PPMS doesn’t feature distinct clinical attacks like RRMS, the criteria for diagnosis is different. According to the National MS Society, the criteria for diagnosis of PPMS are:
One year of disease progression (worsening of neurological function without remission), AND
Two of the following:
- A type of lesion in the brain that is recognized by experts as being typical of MS
- Two or more lesions of a similar type in the spinal cord
- Evidence in the spinal fluid of oligoclonal band or an elevated IgG index, both of which are indicative of immune system activity in the central nervous system
Fulfilling these diagnostic criteria may take years longer for PPMS than the equivalent does for RRMS.
Treatment for PPMS is limited. Although several drugs have been tested in patients with PPMS and research is ongoing, only one agent has been approved by the Food and Drug Administration (FDA) for use by patients with PPMS. In March 2017, the FDA approved Ocrevus (ocrelizumab) — a CD20+ B-cell depletion monoclonal antibody therapy delivered by intravenous infusion every six months — for use in patients with PPMS and RRMS. This disease-modifying therapy is shown to delay progression of disability in patients with PPMS, but does not repair existing neurological damage.
If you are interested in participating in a clinical trial, several studies listed on ClinicalTrials.gov are actively recruiting people with PPMS. The National MS Society also provides information about ongoing and recently completed clinical trials involving people with progressive MS. Finally, the International Progressive MS Alliance provides information about living with PPMS, challenges with understanding the disease, and research projects happening around the world.
Beyond disease-modifying therapy, treatments for people with PPMS center around symptomatic treatments, rehabilitation strategies, use of adaptive equipment, and adaptations at home and work to maintain quality of life. Although patients with any form of MS can experience many of the same symptoms, people with PPMS may experience increased mobility problems earlier in the disease. But even with limited mobility, people with PPMS can continue to be active, even traveling by air with a motorized wheelchair.