We have examined the effi cacy, safety and tolerability of Betaferon in patients with uncertain prognosis in relapsing course of multiple sclerosis (MS). We had performed the evaluation of clinical and radiological effi cacy in 30 patients before the course of treatment, in 24 patients after 12 months period against the background of the treatment, and after 24 months immediately after the course of treatment. We have been considering the frequency and severity of relapses, the dynamics of neurological impairment according to the Expanded Disability Status Score (EDSS) scale and the Kurtzke Expanded Disability Status Scale; Magnetic resonance imaging (MRI) data, obtained before and after the 24-month period of treatment. According the results of our examination, we have developed the criteria of high, moderate and low treatment effi cacy. The high effi cacy was obtained in 33.3 % of patients by the end of Betaferon course. The moderate effi cacy had been defi ned in 29.2 % of patients. The low effi cacy had been defi ned in 16.7 % of patients. We have observed the state stabilization 12.5 % of patients with the absence of clinical and radiological dynamics. We determined the lack of effi cacy in 8.3 % of patients

We have proved the clinical and radiological effi cacy of Betaferon as a fi rst line drug, which modifies the aggressive relapsing course of MS in patients with uncertain prognosis. A signifi cant decrease in the average frequency and severity of relapses, the tendency toward the decrease in the average score of disability, according to the EDSS and Kurtzke scales, combined with a decrease of active gadolinium-enhancing lesions on MRI, helped to extend the recurrent stage and reduced the risk of immediate transformation of relapsing course into the secondary-progressive course.