Long-term subcutaneous interferon beta-1a therapy in patients with relapsing-remitting MS.

Contains fulltext : 50685.pdf (publisher's version ) (Closed access)OBJECTIVE: To conduct systematic long-term follow-up (LTFU) of patients in the Prevention of Relapses and Disability by Interferon beta-1a Subcutaneously in Multiple Sclerosis (PRISMS) study to provide up to 8 years of safety, clinical and MRI outcomes on subcutaneous (s.c.) interferon (IFN) beta-1a in relapsing-remitting multiple sclerosis (RRMS). METHODS: The original cohort of 560 patients was randomized to IFNbeta-1a, 44 or 22 microg three times weekly (TIW) or to placebo; after 2 years, patients on placebo were rerandomized to active treatment and the blinded study continued for a further 4 years. The LTFU visit was scheduled 7 to 8 years after baseline. RESULTS: LTFU was attended by 68.2% of the original PRISMS study cohort (382/560 patients). 72.0% (275/382) were still receiving IFNbeta-1a s.c. TIW. Patients originally randomized to IFNbeta-1a 44 microg s.c. TIW showed lower Expanded Disability Status Scale progression, relapse rate and T2 burden of disease up to 8 years compared with those in the late treatment group. Brain parenchymal volume did not show differences by treatment group. Overall, 19.7% of patients progressed to secondary progressive MS between baseline and LTFU (75/381). No new safety concerns were identified and treatment was generally well tolerated. CONCLUSIONS: Despite the limitations inherent in any long-term study (for example, potential differences between returning and nonreturning patients), these results indicate that patients with relapsing-remitting multiple sclerosis can experience sustained benefit over many years from early interferon beta-1a subcutaneous therapy three times weekly compared with patients whose treatment is delayed. This effect was more apparent in the patients receiving the higher dose

Randomised double-blind placebo-controlled study of interferon beta-1a in relapsing/remitting multiple sclerosis. PRISMS (Prevention of Relapses and Disability by Interferon beta-1a Subcutaneously in Multiple Sclerosis) Study Group.

BACKGROUND: Previous trials of interferon beta in multiple sclerosis (MS) have shown efficacy, but the degree of clinical benefit remains uncertain, and the optimum dose is not known. We undertook a double-blind, placebo-controlled study in relapsing/remitting MS to investigate the effects of subcutaneous interferon beta-1a. METHODS: 560 patients with Kurtzke expanded disability status scale (EDSS) scores of 0-5.0, from 22 centres in nine countries, were randomly assigned subcutaneous recombinant interferon beta-1a 22 microg (n=189), or 44 microg (n=184), or placebo (n=187) three times a week for 2 years. Neurological examinations were done every 3 months. All patients had MRI twice yearly and 205 had monthly scans in the first 9 months of treatment. Analysis was by intention to treat. FINDINGS: Clinical data on 533 (95%) patients were available at 2 years. The relapse rate was significantly lower at 1 and 2 years with both doses of interferon beta-1a than with placebo (mean number per patient 1.82 for 22 microg group, 1.73 for 44 microg group vs 2.56 for placebo group: risk reductions 27% [95% CI 14-39] and 33 [21-44]). Time to first relapse was prolonged by 3 and 5 months in the 22 microg and 44 microg groups respectively, and the proportion of relapse-free patients was significantly increased (p<0.05). Interferon beta-1a delayed progression in disability, and decreased accumulated disability during the study. The accumulation of burden of disease and number of active lesions on MRI was lower in both treatment groups than in the placebo group. INTERPRETATION: Subcutaneous interferon beta-1a is an effective treatment for relapsing/remitting MS in terms of relapse rate, defined disability, and all MRI outcome measures in a dose-related manner, and it is well tolerated. Longer-term benefits may become clearer with further follow-up and investigation