IFN-beta1a may increase serum levels of TIMP-1 in patients with relapsing-remitting multiple sclerosis.

Serum levels of matrix metalloprotease-9 (MMP-9) and tissue inhibitor of MMP-1 (TIMP-1) were measured monthly in 7 patients with relapsing-remitting multiple sclerosis (MS) 6 months before and 6 months during treatment with weekly intramuscular (i.m.) injections of interferon-beta1a (IFN-beta1a) 30 microg. Within-patient median MMP-9 levels were unchanged on treatment. Within-patient median TIMP-1 levels were higher during months 1-6 (771.5 ng/ml) and during months 4, 5, and 6 of treatment (793 ng/ml) compared with 6 months pretreatment (414 ng/ml) (respectively, p = 0.10, p = 0.047; Wilcoxon signed-rank test). These preliminary data suggest that IFN-beta1a therapy may increase TIMP-1 levels.