Comparison of the efficacy and safety of the original rituximab and its biosimilar in routine clinical practice

Abstract

Currently, a biosimilar (BS) of rituximab (RTM) Acellbia® is widely used in Russia for the treatment of rheumatoid arthritis (RA), however, a systematic study of this drug in routine clinical practice has not been conducted.Objective: to compare the results of the use of RTM BS (Acellbia®) and the original rituximab (oRTM) in the daily clinical practice of a large rheumatology center.Patients and methods. The study involved 127 patients predominantly with seropositive RA, who were divided into four groups. Groups 1 and 2 included 66 bionaive patients with active RA and ineffectiveness of previous therapy. 31 patients of the 1st group received 2 infusions of oRTM at a dose of 500 mg intravenously (IV) 2 weeks apart; 35 patients of the 2nd group – 2 infusions of RTM BS at a dose of 500 mg IV 2 weeks apart. Groups 3 and 4 included 61 patients who had previously received oRTM therapy. These patients received 4 courses of oRTM treatment on average before being included in the study. 30 patients of the 3rd group continued oRTM therapy: they received 2 infusions at a dose of 500 mg IV 2 weeks apart; 31 patients of the 4th group received 2 infusions of RTM BS at a dose of 500 mg IV 2 weeks apart.Results and discussion. During the observation period, the dynamics of the main indicators of RA activity in the 1st and 2nd groups did not differ significantly. Although the indication for rehospitalization was an exacerbation of the disease, 64.5% of patients in the 1st and 77.1% of patients in the 2nd group, preserved a 20% improvement according to the ACR criteria on re-examination. The condition of patients of the 3rd and 4th groups remained generally stable during the observation period. The change in the DAS28 index in most cases was clinically insignificant. There were no significant differences in the dynamics of inflammatory activity among patients who continued oRTM treatment and who received RTM BS.Conclusion. The results of the study show that both the prescription of RTM to bionaive RA patients and repeated courses of treatment with RTM BS and oRTM are comparable in terms of efficacy and tolerability.