Multiple sclerosis (MS) is a neurological disease that affects the central nervous system (CNS). It mainly affects the brain, optic nerves, and spinal cord. There are four types of MS: relapsing-remitting MS (RRMS), primary progressive MS (PPMS), secondary progressive MS (SPMS), and clinically isolated syndrome (CIS).

What Is Secondary Progressive MS?

Secondary progressive MS is a form of MS that evolves from RRMS over time. The disease course of MS varies from person to person. Not everyone who has RRMS will develop SPMS. However, women are twice as likely to develop SPMS as compared to men, and SPMS is more common in white people. Genetics and environmental factors also play a role.

There is currently no method for predicting who will develop SPMS. However, it seems that those who have frequent, severe relapses are at a higher risk.

How Does RRMS Transition to SPMS?

In most cases, people with SPMS will have fewer relapses than they would if they had RRMS. This is due to decreased inflammation overall. However, because the disease has continued to progress, the nerves are often damaged beyond repair at this stage, leading to worsening symptoms. This progression in the disease is referred to as secondary progressive. It has this name because a person can only be diagnosed with SPMS if they have previously had RRMS.

The National Multiple Sclerosis Society reported information about the transition from RRMS to SPMS and the length of time it takes to progress to SPMS: 50 percent of people with RRMS progress in 10 years, and 90 percent would transition in 25 years. The average age seen at the transition to SPMS is 40 years old.

Diagnosing SPMS

At first, it may be difficult to discover the transition between RRMS and SPMS. A neurologist (a doctor who specializes in treating disorders of the nervous system) will take a detailed medical history and perform a physical examination. People who have been previously diagnosed with RRMS will be asked about their symptoms, relapses, and remissions to determine if the disease is progressing. Magnetic resonance imaging (MRI) scans may also be used to scan the brain and spinal cord for MS lesions.

Symptoms of Secondary Progressive MS

SPMS symptoms are similar to those seen in PPMS. These include:

• Numbness or tingling
• Fatigue
• Muscle spasms (spasticity) or stiffness
• Vision problems, such as loss of vision in one eye or double vision
• Difficulty with cognition (learning and memory)
• Unsteady walking and balance problems
• Issues with bladder and bowel control

Some people with SPMS may experience flare-ups or remission of symptoms. Because the disease has progressed so far, remissions may not be complete, and some symptoms may still occur.

Read more about the signs and symptoms of SPMS here.

How Are These Conditions Treated?

SPMS is treated with medications known as disease-modifying therapies (DMTs). DMTs have been shown to slow the progression of MS. There is no cure for SPMS, but symptoms can be managed to improve your well-being. Your neurologist should let you know about the side effects of these DMTs.

Rebif

Rebif (interferon beta) is a medication approved by the U.S. Food and Drug Administration (FDA) to treat active SPMS, RRMS, and CIS in adults. It contains interferon-beta 1A, which is a protein produced by the body’s immune system. This protein acts as an immunomodulator. This means that it reduces inflammation, which in turn helps prevent further nerve damage. Rebif is injected into the muscle once per week to help manage SPMS symptoms.

Copaxone

Copaxone (glatiramer acetate) is an FDA-approved medication used for treating active SPMS, RRMS, and CIS. The medication is taken by injection and contains an artificial protein that imitates myelin basic protein. This protein makes up the myelin that covers nerve fibers in the brain and spinal cord. Copaxone has also been shown to stop immune cells from attacking and damaging myelin. The mechanism by which Copaxone works for this purpose is not completely understood.

Novantrone

Novantrone (mitoxantrone) is a chemotherapy medication typically used to treat people with cancer. However, the FDA has also approved it for the treatment of SPMS or progressive or worsening RRMS. Novantrone works by breaking the DNA of immune cells and preventing them from replicating. This leads to less inflammation in the brain and spinal cord. Novantrone must be administered under the care of a doctor trained in chemotherapy, compared to other SPMS medications given as pills or simple injections.

Zeposia

Zeposia (ozanimod) is an FDA-approved medication used for treating active SPMS, RRMS, and CIS in adults. Zeposia works by preventing white blood cells from leaving the lymph nodes so they cannot cross the blood-brain barrier and enter the CNS. This effect reduces overall inflammation and can help protect the nerve cells from further damage.

Mayzent

Mayzent (siponimod) is an FDA-approved medication used for treating SPMS, RRMS, and CIS. Clinical trials found that Mayzent reduced the risk of worsening disability in people with SPMS by 21 percent, and reduced the risk of relapses by 55 percent. Side effects include headaches, urinary tract infections, falls, and common colds.

Mavenclad

Mavenclad (cladribine) belongs to the class of medications known as purine antimetabolites. These medications interfere with DNA processes in cells and can be used to prevent specific immune cells from replicating. In people with MS, Mavenclad is used to help control the inflammation that damages nerve fibers.

Talk With Others Who Understand

MyMSTeam is the social network for people with multiple sclerosis and their loved ones. On MyMSTeam, more than 167,000 members come together to ask questions, give advice, and share their stories with others who understand life with MS.

Are you living with MS? Share your experience in the comments below, or start a conversation by posting on your Activities page.