Effectiveness of dimethyl fumarate as first line therapy in MS patients - one center real life observation study

Interferon β, glatiramer acetate and dimethyl fumarate are first line of disease-modifying therapies for patients who have got relapsingremitting multiple sclerosis (RRMS). Currently, there are no precise guidelines for modifying treatment. This is the individual decision of the attending physician, which should take into account both the clinical course of the disease and the patient's preferences. Therefore, possible findings of this study may potentially improve treatment strategy and could be helpful for the clinicians to select the most appropriate therapy.

The aim of this study was to evaluate and compare activity of multiple sclerosis one year before and one year after switching treatment from interferon β or glatiramer acetate to dimethyl fumarate. The reasons for treatment modification and impact of these reasons on therapy effectiveness were studied as a secondary outcome.

This observational and retrospective study among patients with RRMS lasted for 2 years and was conducted at one medical center. Participants of the study were aged 19-61 years. All of them had been initially treated with disease-modifying drugs (DMDs) by injection: interferon or glatiramer acetate. After one-year observation patients switched therapy to dimethyl fumarate (DMF) for various reasons.

62 adult patients received interferon beta or glatiramer acetate in the first year. After a year all of them switched from that therapy to dimethyl fumarate. Patients in all treatment groups had similar demographic and clinical characteristics at baseline. The most common reason for change in interferon β group were adverse effects or clinical ineffectiveness. Patients from glatiramer acetate group most often changed their therapy due to new lesions on MRI scans. Presented study shows a statistically significant decrease in radiological relapse when changing treatment from glatiramer acetate to dimethyl fumarate. At the same time, switching from interferon to dimethyl fumarate reduced the number of clinical relapses. There was no statistically significant difference in EDSS scores before and after treatment change in interferons' β and glatiramer acetate's groups.

The results of our study show that patients with progression of the disease should be treated with another medication. Further research is necessary to develop therapeutic position that supports therapeutic decision in an early period of MS. The observation of the presented group of patients will be continued.