COMPARATIVE EVALUATION OF THE EFFICACY AND SAFETY OF ABATACEPT IN PATIENTS WITH DIFFERENT DURATION OF RHEUMATOID ARTHRITIS

Objective : to compare the efficacy and safety of abatacept (ABC) in patients with different duration of rheumatoid arthritis (RA). Subjects and methods. The investigation enrolled 86 patients with previous inefficiency or intolerability of therapy with synthetic disease-modifying antirheumatic drugs (DMARDs), mainly with methotrexate, and/or biological agents (BAs), such as adalimumab, etanercept, rituximab, infliximab, certolizumab pegol, and tocilizumab. The patients were divided into 2 groups. Group 1 included 29 (34%) patients with early RA ( 2 years' disease duration). The patients' mean age was 49±13.4 years; most of them were women who had a high RA activity (the mean DAS28 value was 5.2±1.15), were seropositive for rheumatoid factor and anti-cyclic citrullinated peptide antibodies. All the patients underwent standard clinical and laboratory examinations. ABC was injected intravenously at a dose of 10 mg/kg according to the standard regimen. Every 3 months, disease activity was assessed with DAS28; functional status was evaluated with the Health Assessment Questionnaire (HAQ). Results and discussion. In the early and advanced RA patients, the mean DAS28 at baseline was 5.2±0.9 and 5.2±1.3, respectively. After 3 months of ABC treatment, it significantly decreased in both groups (p < 0.05). An improvement according to the criteria of the European League Against Rheumatism (EULAR) occurred in 76% of the early RA patients and in 74.5% of the advanced RA ones. Following 3 and 6 months of therapy, there were no significant differences between the two groups in the rate of a good response: the latter was obtained in 31 and 42% of early RA cases and in 25.5 and 40% of advanced RA cases, respectively. After 3 and 6 months, both groups showed a comparable number of those who did not respond to treatment (24 and 12.5% in the early RA group and 25.5 and 25% in the advanced RA group, respectively). During ABC therapy, both groups also displayed a significant decrease of HAQ disability index (DI) (p < 0.05). A total of 14 adverse events (AE) were recorded in 13 (15%) patients. The most common AE proved to be acute respiratory viral infections that were observed in 6 (7%) patients. Serious AE were seen in 3 (3.4%) patients.   Conclusion. ABC therapy leads to decrease of RA activity in the majority of patients who have previously received ineffective therapy with DMARDs and BAs. There were no significant differences in good response rates according to the EULAR criteria between the advanced and early RA groups. Following 3 months of treatment, the decrease of HAQ DI was significantly more pronounced in the early RA group. AE were registered only in 15% of the patients. ABC has established itself as an effective drug that has a good safety profile and is able to occupy a niche in the therapy of both late and early RA.