Authors have followed up 230 patients with multiple sclerosis treated with disease modifying drugs (DMD) using the data of the Multiple sclerosis register of the Yaroslavl oblast during 2009-2011. Original drugs and their generics registered in Russia are used. Patients received interferon-beta 1a for intramuscular introduction (avonex - 3.0%), interferon-beta 1a for hypodermic injection (rebif - 19.2%, genfakson - 8.5%), interferon-beta 1b (betaferon - 16.5%, extavia - 18.2%, ronbetal - 18.0%), glatimer acetate (copaxone - 16.7%). Adverse effects were recorded and subjective tolerability of the drug by the patient was assessed. Statistically significant differences in the safety profile between some bioanalogues and original DMD were identified. This finding suggests that effects of different DMD should be studied in depth in clinical and post marketing trials.