NEW YORK (Reuters Health) – In patients with relapsing-remitting multiple sclerosis (MS) and high disease activity, valacyclovir treatment may reduce the number of new active lesions observed on MRI, Scandinavian investigators report.
Dr. Johannes Jakobsen, of Aarhus University Hospital in Denmark, and colleagues randomized 70 MS patients who had at least two relapses during the preceding two years to treatment with valacyclovir 1000 mg t.i.d, or placebo. After 24 weeks of treatment, there were no significant differences between the two treatment groups in terms of Expanded Disability Status Scale scores or Regional Functional Scoring System scores.
However, as the researchers report in Neurology for January 8, significant differences showed up among individuals who had more than one active MRI-evident lesion at baseline. The median number of new lesions per 4 weeks was 6.5 among the 11 subjects treated with placebo compared with 2.0 among the 17 treated with the antiviral (p = 0.025). The proportion of MRI scans without evidence of active lesions also differed significantly (p < 0.001).
"It is possible that certain patients with MS with severe disease activity will benefit from treatment with valacyclovir," Dr. Jakobsen's group concludes.
Dr. Andrew D. Goodman, of the University of Rochester in New York, and Dr. David H. Miller, of the University College London in the UK, caution that the results reported here could be misleading due to the small number of highly active patients. Also, no evidence of an antiviral effect was demonstrated, and there were no signs of clinical benefit.
The two editorialists suggest that more potent and specific antiviral therapies for Epstein-Barr virus and for human herpesvirus 6 are needed before an etiopathogenic role for an infectious agent in MS can be confirmed.