Abstract :
PURPOE: To evaluate the effect of treatment with interferon β-1a (Avonex) initiated at the time of a firt epiode of optic neuriti in patient at high rik for multiple cleroi (M).
DEIGN: Randomized clinical trial
METHOD:
Propective.
ETTING: Fifty clinical center throughout the U and Canada.
TUDY POPULATION: After the onet of a firt epiode of optic neuriti treated with intravenou and oral corticoteroid, 192 patient with brain magnetic reonance imaging (MRI) evidence of ubclinical demyelination were randomly aigned to receive weekly intramucular injection of 30 μg interferon β-1a or placebo.
MAIN OUTCOME MEAURE: The tudy outcome were the development of clinically definite M within 3 year of follow-up and brain MRI change at 6, 12, and 18 month.
REULT: The rate of clinically definite M and of a combined M/MRI outcome were lower in the interferon β-1a group than in the placebo group (adjuted rate ratio 0.58, 95% confidence interval 0.34 to 1.00; and 0.50, 95% confidence interval 0.34 to 0.73, repectively). Compared with the placebo group, on the 18-month brain MRI the interferon β-1a group had a maller change from baeline in T2 leion volume (P = .02), fewer new or enlarging T2 leion (P < .001), and a lower frequency of Gd-enhancing leion (P < .001).
CONCLUION: The clinical and brain MRI reult of thi trial upport initiating interferon β-1a treatment at the time of a firt epiode of optic neuriti occurring in patient at high rik for M baed on the preence of ubclinical brain MRI leion
