Evaluation of Effectiveness of Long-Term Therapy with Russian Rituximab Biosimilar (Acellbia) in Sjogren's Disease in Real Clinical Practice.

The aim to evaluate the effectiveness of long-term therapy with Russian rituximab (RTX) biosimilar in Sjögren's disease (SjD) in real-life clinical practice. MATERIALS AND 

methodsThe retrospective study included 53 patients with SjD (Russian 2001 criteria and ACR/EULAR (American College of Rheumatology/European Alliance of Associations for Rheumatology) 2016 criteria), observed at the Nasonova Research Institute of Rheumatology from 2017 to 2024 and receiving long-term RTX therapy (Russian biosimilar Acellbia®, BIOCAD). The signs of clinical and laboratory activity of the disease, stomatological and ophthalmological tests, as well as the incidence of new systemic manifestations and lymphomas were assessed dynamically.

resultsThe median duration of RTX therapy was 27 [19; 55] months, and the median total dose was 4 [3.5; 5.5] g. Before the therapy, 13 (25%) patients had recurrent parotitis, which was relieved in all patients during the therapy. Persistent enlargement of the salivary glands was observed in 10 (20.4%) patients, in 9 of them it was relieved. A significant increase in stimulated saliva flow was found (from 1.5 [0.5; 3] to 2.4 [1.4; 3.5] mL; p = 0.002), an increase in salivation was found in 51% of patients, stabilization in 28.6%, and deterioration in 20.4%. When assessing the ultrasound dynamics of the salivary glands, the size of hypoechoic avascular lesions significantly decreased (from 1.8 [1.3; 2.3] to 1.3 [1.1; 1.5] mm; p<0.001), and according to the ultrasound activity index, stabilization was noted in 67.4% of patients, improvement in 27.9%, and deterioration in 4.7% of patients. When assessing the dynamics of sialography, the size of cavities significantly decreased (from 1.5 [1.5; 2.5] to 1.0 [0; 1.5] mm; p < 0.001), and according to the assessment of sialographic stages, stabilization was noted in 67.5% of patients, improvement in 32.5% of patients, and deterioration was not noted in any patient. When assessing the lacrimal glands function, a significant increase in lacrimation was found according to the stimulated Schirmer's test (from 6 [3.75; 12] to 8 [5; 15] mm; p = 0.005); an increase in lacrimation was noted in 38% of patients, stabilization in 40.6%, and a decrease in 21.4%. When assessing the tear break-up time, a tendency towards its increase was noted, but statistically insignificant (from 5 [3.75; 9.25] to 5.5 [4; 9] sec; p = 0.35). Corneal epitheliopathy during the therapy was relieved in 44% and persisted in 56% of patients; worsening of corneal epitheliopathy during the treatment was observed in a few patients, while no cases of ulcer formation or perforation of the cornea were recorded. During the therapy, a significant decrease in the levels of erythrocyte sedimentation rate, gamma globulins, IgG, IgA, IgM, rheumatoid factor, an increase in the C3 complement level, and the elimination of monoclonal gammopathy were observed, while the dynamics of the C4 complement level and cryoglobulinemia were multidirectional. The median duration of B lymphocyte depletion was 5 [4; 6] months, constant depletion could be maintained only in 59.6% of patients. During the therapy, the SjD systemic activity index (ESSDAI, EULAR Sjögren's Syndrome Disease Activity Index) significantly decreased (from 5 [2; 8] to 1 [0; 3] points; p<0.001), and minimal clinically important improvement of this index was achieved in 66.6% of patients. During the observation, one patient developed a new skin lesion (lupus chilblain); no other new systemic manifestations or lymphomas were registered.

conclusionsAccording to our retrospective study conducted in real-life clinical practice, long-term therapy with Russian RTX biosimilar in most cases (60-80%) led to stabilization or improvement of SjD manifestations. RTX can be used to treat not only systemic but also glandular manifestations of the disease. Given the lack of an optimal response to RTX therapy in a number of SjD patients, it is necessary to study the effectiveness of drugs that lead to a deeper depletion of B lymphocytes.