The purpose of the study is to determine if lipoic acid can preserve mobility and protect the brain in progressive forms of multiple sclerosis.

This two-year study will determine if daily oral intake of lipoic acid will prove superior to placebo in reducing injury to the brain and maintaining mobility in progressive MS. Mobility will be assessed with the timed 25-foot walk test and 2-minute timed walk test as well as fall counts. Neuroprotection will be measured by the extent of brain volume loss seen on MRI.

Inclusion Criteria:

• Diagnosis of progressive MS as defined by the study
• Able to give informed consent and to adhere to study procedures.
• Expanded Disability Status Scale (EDSS) 3.0 - 6.5: ambulatory for at least 20 meters without rest and use of bilateral aids (canes, crutches, walker) or better.

Exclusion Criteria:

• A self-reported medical or neurological problem other than MS that is a cause of progressive or fluctuating gait dysfunction
• Unable to undergo MRI
• Unable to follow directions in English as standardized scales are not all validated in other languages.
• Current major disease or disorder other than MS (e.g., cancer, renal disease, end-stage cardiopulmonary disease, post-traumatic stress disorder, etc.) that may interfere with study procedures. Note: Stable abnormal laboratory values of no more than Grade 1 determined to not be of clinical significance to the primary treating physician for that condition may be permitted per local site investigator discretion.
• Pregnant or breast-feeding.
• Insulin-dependent diabetes or diabetes not controlled on oral diabetes medications.
• Scheduled (every 3 months or more frequently) IV or oral steroids in the year prior to enrolment.
• IV or oral steroids in the 60 days prior to enrolment.
• Use of LA in the prior 2 years exceeding the equivalent of 1200mg daily for 3 months.
• Participation in the pilot LA in SPMS trial.

2 years of treatment

AE and laboratory abnormalities were captured and categorized using the Common Terminology Criteria for Adverse Events version 5.0 (CTCAE v5.0). The Suicide Behaviors Questionnaire-Revised (SBQ-R) was used to monitor for suicidality as required by the Food & Drug Administration.

Limitations of the study include issues of low power, COVID-19 pandemic interruptions in study recruitment and data collection, and unexpected study withdrawals due to proteinuria.