The purpose of the study is to determine if lipoic acid can protect the brain and slow disability in secondary progressive multiple sclerosis.

There are no approved medications that are neuroprotective or able to slow disability accumulation in secondary progressive multiple sclerosis (SPMS). This two-year study will determine if daily oral intake of lipoic acid, a natural supplement, will prove superior to placebo in reducing injury to the brain and reducing disability progression in SPMS. Neuroprotection will be measured by the extent of brain volume loss seen on MRI, and disability will be measured by neurological status and quality of life.

Inclusion Criteria:

• Diagnosis of SPMS
• Age 40-70 years
• Able to understand English and able to give informed consent

Exclusion Criteria:

• Unable to undergo MRI testing
• For ambulatory subjects only, a self-reported medical or neurological condition other than MS that is a cause of progressive or fluctuating problems that affect walking(e.g. worsening neuropathy, uncontrolled lower extremity arthritis, uncontrolled heart or lung disease)
• For ambulatory subjects only, fixed and/or stable conditions of less than 1 years duration that affect walking (e.g. joint replacement, lumbar stenosis, alcoholism, stroke, etc.)
• Pregnant or breast-feeding.
• Current major disease or disorder other than MS (such as cancer, kidney, heart or lung disease, post-traumatic stress disorder) that may interfere with study procedures
• Natalizumab, mitoxantrone, azathioprine taken in the last 12 months
• Other immunosuppressants or chemotherapies taken in the last 12 months
• Scheduled (every 3 months or more frequently) IV steroids used in the last 12 months
• IV or oral steroids taken in the past 60 days.
• Lipoic acid taken in the past 60 days.
• Subject has insulin-dependent diabetes or is not controlled on oral diabetes medications