TORONTO, ON -- June 7, 1999 -- Data from, SPECTRIMS, the first clinical trial of Ares-Serono’s Rebif (recombinant interferon beta-1a), show that the drug is safe and effective in the treatment of secondary progressive multiple sclerosis (SPMS).
Rebif is currently indicated for the treatment of relapsing-remitting MS.
Key findings from the study included a reduction in the number and severity of relapses suffered by patients, an increase in the number of patients remaining relapse-free and a decrease in disease activity and burden of disease as measured by magnetic resonance imaging (MRI). In addition, the highest dose of interferon beta-1a was more effective, reinforcing the dose-effect relationship seen in previous trials with less advanced patients. Time to disability progression was not significantly delayed unless baseline disease severity was taken into account, and then only at the high dose.
"These results indicate that Ares-Serono's interferon beta-1a is beneficial for patients with secondary progressive disease and show that the dose-effect relationship seen in previous trials translates to more seriously-compromised patients," said Donald Paty, MD, professor of neurology at the University of British Columbia and a principal investigator in SPECTRIMS. "As we expected, the efficacy of interferon beta-1a in secondary progressive MS is not as pronounced as in relapsing-remitting disease because of the advanced nature of secondary progressive disease, which is characterised by a greater degree of irreversible axonal damage and demyelination.
"These new data underscore the need to treat MS early and with the highest tolerable doses of beta interferon."
Researchers in seven European countries, Australia and Canada randomised 618 patients to receive either placebo, interferon beta-1a 22mcg or 44mcg subcutaneously three times per week for three years. Full three-year data were available for 92 percent of the patients. The patient population in SPECTRIMS suffered from the most advanced MS ever studied with interferon beta. Compared to previous trials at baseline, there was a lower proportion of relapsing patients and they had higher disability, a longer duration of SPMS, were older and suffered from a high burden of disease, as measured by MRI.
Outcomes were positive for the major clinical measures. Overall, tolerability was good with a side-effect profile similar to that found in the PRISMS trial. Patients treated with interferon beta-1a 44mcg three times per week benefited more consistently than those on the lower dose (interferon beta-1a 22 mcg three times/week). There was also a lower incidence of neutralising antibodies in the high-dose arm. Interferon beta-1a significantly reduced the number of relapses, by about one third. Additionally, relapses were less severe, time to first relapse was prolonged and the proportion of relapse-free patients was increased, especially in the high-dose arm.
The effects of interferon beta-1a on disease burden and the number of active lesions as measured by MRI were also significant for both doses. Patients on placebo experienced an increase in disease burden, while it actually decreased in treated patients.
The number of active lesions was significantly reduced in both treatment
groups compared to placebo. Furthermore, significantly more patients receiving
interferon beta-1a had no active lesions at the end of the study, compared
with placebo, with the best result achieved in the high-dose arm. Interferon
beta-1a also reduced the number of hospitalisations and the need for steroid
treatment compared to placebo. An estimated two million people world-wide
are living with multiple sclerosis, a chronic, debilitating disease of
the central nervous system that affects mainly young adults. MS has an
unpredictable clinical course and several clinical patterns -- the most
common of which are relapsing-remitting and secondary-progressive MS. At
present, most patients with MS will become increasingly disabled, but recent
data suggest that new therapies such as Rebif may beneficially affect the
long-term course of MS.