Clinical and immunological effects of the original and biosimilar rituximab in patients with rheumatoid arthritis

Aim

To evaluate the changes in acute phase reactants, autoantibodies, immunoglobulins, CD19+B lymphocytes in patients with rheumatoid arthritis (RA) during treatment with the original and biosimilar rituximab (RTX).

Material and methods

We recruited 54 RA patients who were distributed into two groups. Thirty four patients from the first group received two infusions of the original RTX, whereas twenty patients from the second group were treated with two infustions of the biosimilar RTX (BCD-020). At baseline and at weeks 12 and 24 after the first infusion of RTX, we evaluated ESR, serum concentrations of CRP, IgM RF, IgA RF, anti-CCP2, and anti-MCV.

Results

At weeks 12 and 24, both RTX and BCD-020 decreased ESR, CRP, IgM RF, IgA RF, and anti-MCV (p<0.05). At week 24, 20% and 10% of IgM RF positive patients from the two groups, respectively, turned negative. Anti-CCP2 levels did not change significantly. At week 24, anti-CCP2 were not detected in 7% and 15% of patients from the two groups, respectively, who initially tested positive for these antibodies. Complete depletion of CD19+B-cells was achieved at week 12 in all patients, with an increase in the B cells count at week 24. The immunoglobulins levels decreased at week 24, however, they remained in the normal range.

Conclusion

The original and biosimilar RTM have similar effects on inflammatory and immunological biomarkers in RA patients and induced a rapid and significant decrease in ESR, CRP, IgM/IgA RF, anti-MCV levels, and CD19+B cells depletion.

Key words

Rheumatoid arthritis, rituximab, biosimilar, disease activity, immunological parameters.