• Also known as: Plaquenil
  • Route and Dose of Administration: Oral (400 mg daily given as two doses of 200 mg)
  • Emerging Treatment for: Primary Progressive Multiple Sclerosis (PPMS)
  • Status: In Phase II clinical trial

Hydroxychloroquine is currently approved in Canada to treat malaria and rheumatic diseases, such as Systemic Lupus Erythematodes (SLE) and Rheumatoid Arthritis (RA). The use of hydroxychloroquine in treating MS is an example of drug repurposing, a process in which a commercially available drug is evaluated for the treatment of a different condition

How it works

Hydroxychloroquine has been shown to reduce disease activity in animals with MS-like disease by decreasing the activity of specific immune cells in the brain and spinal cord called microglia. Under normal conditions, microglia cells have beneficial roles in the central nervous system by clearing away debris. However, in PPMS, these cells are in a constant state of activation and may potentially contribute to the ongoing damage to nerve cells.

Research and Results

Phase II Trial

In a small phase II, interventional clinical trial led by Canadian researchers at the University of Calgary and MS Clinic Foothills Medical Centre, 35 adults will be recruited to determine if treatment with hydroxychloroquine (400 mg daily) for up to 18 months can prevent worsening of walking ability in individuals with PPMS. The primary outcome measures will evaluate improvements to the time required to walk 25 feet (measured using the Timed 25-Foot Walk test). The trial will also assess upper extremity function (measured using the 9-Hole Peg Test), cognition, processing speed and working memory (measured using Symbol Digit Modalities Test), as well as the quality of life of study participants.

Results: Hydroxychloroquine as a Potential Treatment for Primary Progressive MS


Record on ClinicalTrials.gov: Hydroxychloroquine in Primary Progressive Multiple Sclerosis