Acyclovir treatment of relapsing-remitting multiple sclerosis. A randomized, placebo-controlled, double-blind study

Area of Science:

• Neuroscience
• Virology
• Immunology

Background:

• Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system.
• The role of herpes virus infections in the pathogenesis of MS remains unclear.
• Understanding potential viral triggers is crucial for developing effective MS therapies.

Purpose of the Study:

• To investigate the efficacy of acyclovir in reducing exacerbation rates in patients with relapsing-remitting MS.
• To test the hypothesis that herpes viruses contribute to MS pathogenesis.
• To evaluate the impact of acyclovir on clinical disease activity and neurological parameters.

Main Methods:

• A 2-year, randomized, double-blind, placebo-controlled trial involving 60 MS patients.
• Patients received either oral acyclovir (800 mg three times daily) or placebo.
• Clinical outcomes were assessed using neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials.

Main Results:

• Acyclovir treatment resulted in a 34% lower annual exacerbation rate compared to placebo (1.03 vs. 1.57), though not statistically significant overall (P=0.083).
• Subgroup analyses revealed a significant reduction in exacerbations for acyclovir-treated patients when grouped by frequency (P=0.017) and in those with disease duration of at least 2 years (P=0.024).
• Neurological parameters and deterioration were not significantly affected by acyclovir treatment.

Conclusions:

• Acyclovir treatment may inhibit the triggering of MS exacerbations.
• These findings suggest that acyclovir-susceptible viruses might be involved in the pathogenesis of MS.
• Further investigation into the viral etiology of MS is warranted.