Search for agents for the add-on therapy of multiple sclerosis (MS) that can enhance the effect of first-line MS disease-modifying therapy (DMTs) is a very current issue. Such a boost is needed to reduce the need to switch to second-line DMTs, whose pathogenetic therapy leads to severe side effects in many cases. Curcumin, a natural polyphenol, has immunoregulatory properties and a favorable safety profile. At the same time, micellar forms of curcumin can increase its bioavailability.Objective: to investigate the effect of the micellar form of curcumin on clinical parameters in MS patients receiving first-line DMTs.Material and methods. MS patients (n=40) receiving interferon-β (IFNβ) therapy who showed a suboptimal response were randomly divided into two groups, one group received additional therapy (dietary enrichment for 6 months) with curcumin in micellar form, the second group did not receive dietary curcumin. At the beginning and end of the study, the disease activity (clinical and radiological), the degree of disability on the EDSS scale, the severity of chronic fatigue on the MFIS scale, the quality of life on the SF-36 scale and the level of cytokines (interleukin 6 and IFNγ) in the blood plasma were determined. Adverse events were also recorded during the observation period and the safety of the therapy was assessed based on the results of general and biochemical blood tests.Results. In the group of patients whose diet was enriched with curcumin, quality of life indicators improved both in the physical component (from 50.2±6.4 to 52.5±6.8; p=0.03) and in the psychological component (from 42.9±15.9 to 45.6±15.5; p=0.02). In the group receiving curcumin, the proportion of patients with exacerbations over 6 months also decreased – from 45 to 9 % (p=0.01). After 6 months of dietary enrichment, lower plasma levels of IFNγ were observed in patients receiving curcumin than in the group without dietary enrichment. No adverse events were noted during the observation period.Conclusion. The preliminary results allow us to consider micellar forms of curcumin, which have an acceptable tolerability and safety profile, as a potential additional method to increase the efficacy of first-line DMTs in MS patients with suboptimal response to IFNβ.