Placebo-controlled multicentre randomised trial of interferon beta-1b in treatment of secondary progressive multiple sclerosis. European Study Group on interferon beta-1b in secondary progressive MS. 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. A single-center, randomized, double-blind, placebo-controlled study of interferon beta-1b on primary progressive and transitional multiple sclerosis. Intramuscular interferon beta-1a therapy initiated during a first demyelinating event in multiple sclerosis. CHAMPS Study Group.
The beneficial effects of interferon beta have only been shown for patients in the relapsing-remitting phase of multiple sclerosis (MS). The role of interferon beta in the treatment of patients who are in the secondary progressive phase of the disease (SP-MS), and for whom no effective drug treatment is available, has not been assessed.
                In this multicentre, double-masked, randomised, placebo-controlled trial, outpatients with SP-MS having scores of 3.0-6.5 on the Expanded Disability Status Scale (EDSS) received either 8 million IU interferon beta-1b every other day subcutaneously, or placebo, for up to 3 years. The primary outcome was the time to confirmed progression in disability as measured by a 1.0 point increase on the EDSS, sustained for at least 3 months, or a 0.5 point increase if the baseline EDSS was 6.0 or 6.5. A prospectively planned interim analysis of safety and efficacy of the intention-to-treat population was done after all patients had been in the study for at least 2 years.
                358 patients with SP-MS were allocated placebo and 360 were allocated interferon beta-1b; 57 patients (31 placebo, 26 interferon beta-1b) were lost to follow-up. There was a highly significant difference in time to confirmed progression of disability in favour of interferon beta-1b (p=0.0008). Interferon beta-1b delayed progression for 9-12 months in a study period of 2-3 years. The odds ratio for confirmed progression was 0.65 (95% CI 0.52-0.83). This beneficial effect was seen in patients with superimposed relapses and in patients who had only progressive deterioration without relapses. Positive results were also obtained regarding time to becoming wheelchair-bound, relapse rate and severity, number of steroid treatments and hospital admissions, as well as on magnetic resonance imaging variables. The drug was safe and side effects were in line with previous experience with interferon beta-1b. The study was stopped after the interim results gave clear evidence of efficacy.
                Treatment with interferon beta-1b delays sustained neurological deterioration in patients with SP-MS. Interferon beta-1b is the first treatment to show a therapeutic effect in patients with SP-MS. 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.
                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.
                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.
                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. Inflammation and neurodegeneration may have differential impacts on disease evolution in the different forms of multiple sclerosis. However, a beneficial effect of immunomodulatory drugs should not be ruled out in primary progressive multiple sclerosis. Our aim is to investigate the safety and efficacy of interferon beta-1b in primary progressive multiple sclerosis. We conducted a double-blind, stratified, randomized, parallel group, phase II pilot study where patients with primary progressive multiple sclerosis or 'transitional' forms of multiple sclerosis received interferon beta-1b at doses of 8 MIU or placebo for 24 months. The main objective of the study was to investigate the safety and tolerability of interferon beta-1b. The primary efficacy variable was the time to neurological deterioration (Expanded Disability Status Scale) confirmed at 3 months. Seventy-three patients were included and three dropped out the study. More patients in the treatment arm had at least one related adverse event (94.4% versus 45.9%; p < 0.001); no other significant differences in safety endpoints were observed. Time to neurological deterioration was not different between trial arms (log-rank test, p = 0.3135). Statistically significant differences favoring treatment were observed for the Multiple Sclerosis Functional Composite score at several timepoints, T1 and T2 lesion volume changes at 12 and 24 months, mean number of active lesions and proportion of patients with active lesions at 24 months. We conclude that interferon beta-1b is safe and well tolerated in patients with primary progressive multiple sclerosis and transitional multiple sclerosis. Positive effects of interferon beta on secondary clinical and magnetic resonance imaging outcomes were observed, but a beneficial effect on Expanded Disability Status Scale progression was not demonstrated. Treatment with interferon beta has been shown to help patients with established multiple sclerosis, but it is not known whether initiating treatment at the time of a first clinical demyelinating event is of value.
                We conducted a randomized, double-blind trial of 383 patients who had a first acute clinical demyelinating event (optic neuritis, incomplete transverse myelitis, or brain-stem or cerebellar syndrome) and evidence of prior subclinical demyelination on magnetic resonance imaging (MRI) of the brain. After initial treatment with corticosteroids, 193 patients were randomly assigned to receive weekly intramuscular injections of 30 microg of interferon beta-1a and 190 were assigned to receive weekly injections of placebo. The study end points were the development of clinically definite multiple sclerosis and changes in findings on MRI of the brain. The trial was stopped after a preplanned interim efficacy analysis.
                During three years of follow-up, the cumulative probability of the development of clinically definite multiple sclerosis was significantly lower in the interferon beta-1a group than in the placebo group (rate ratio, 0.56; 95 percent confidence interval, 0.38 to 0.81; P=0.002). As compared with the patients in the placebo group, patients in the interferon beta-1a group had a relative reduction in the volume of brain lesions (P<0.001), fewer new or enlarging lesions (P<0.001), and fewer gadolinium-enhancing lesions (P<0.001) at 18 months.
                Initiating treatment with interferon beta-1a at the time of a first demyelinating event is beneficial for patients with brain lesions on MRI that indicate a high risk of clinically definite multiple sclerosis.
The evidence from randomised trials does not show significant benefit from azathioprine, interferon beta-1a or methotrexate but none of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures and longer durations.