CD7 activation regulates cytotoxicity-driven pathology in systemic sclerosis, yielding a target for selective cell depletion.

OBJECTIVES: Cytotoxic T cells and natural killer (NK) cells are central effector cells in cancer and infections. Their effector response is regulated by activating and inhibitory receptors. The regulation of these cells in systemic autoimmune diseases such as systemic sclerosis (SSc) is less defined. METHODS: We conducted ex vivo analysis of affected skin and blood samples from 4 SSc patient cohorts (a total of 165 SSc vs 80 healthy individuals) using single-cell transcriptomics, flow cytometry and multiplex immunofluorescence staining. We further analysed the effects of costimulatory modulation in functional assays, and in a severely affected SSc patient who was treated on compassionate use with a novel anti-CD3/CD7 immunotoxin treatment. RESULTS: Here, we show that SSc-affected skin contains elevated numbers of proliferating T cells, cytotoxic T cells and NK cells. These cells selectively express the costimulatory molecule CD7 in association with cytotoxic, proinflammatory and profibrotic genes, especially in recent-onset and severe disease. We demonstrate that CD7 regulates the cytolytic activity of T cells and NK cells and that selective depletion of CD7+ cells prevents cytotoxic cell-induced fibroblast contraction and inhibits their profibrotic phenotype. Finally, anti-CD3/CD7 directed depletive treatment eliminated CD7+ skin cells and stabilised disease manifestations in a severely affected SSc patient. CONCLUSION: Together, the findings imply costimulatory molecules as key regulators of cytotoxicity-driven pathology in systemic autoimmune disease, yielding CD7 as a novel target for selective depletion of pathogenic cells.

Subjective Complaints as the Main Reason for Biosimilar Discontinuation After Open-Label Transition From Reference Infliximab to Biosimilar Infliximab.

OBJECTIVE: To evaluate drug survival, effectiveness, pharmacokinetics, immunogenicity, and safety in daily practice after transitioning treatment from original reference infliximab (Remicade [REM]) to a biosimilar infliximab (CT-P13 [Remsima; Inflectra]) in patients with rheumatoid arthritis, psoriatic arthritis, or ankylosing spondylitis. METHODS: Of the initial 222 REM-treated patients, 192 agreed to transition to CT-P13 and were included in this multicenter prospective cohort study. Changes in the Disease Activity Score in 28 joints using the C-reactive protein level (DAS28-CRP) and the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and changes in the CRP levels, infliximab trough levels, and anti-infliximab antibody levels were assessed after 6 months, and adverse events (AEs) were documented. Drug survival and prognostic factors were analyzed using Kaplan-Meier and Cox regression analyses. RESULTS: During 6 months follow-up, 24% of the patients (n = 47) discontinued CT-P13. Thirty-seven patients restarted REM, 7 switched to another biologic drug, and 3 continued without a biologic drug. The DAS28-CRP remained stable from baseline to month 6, with a mean ± SD score of 2.2 ± 0.9 at baseline to 2.2 ± 0.8 at 6 months (difference of 0.0 [95% confidence interval (95% CI) -0.1, 0.2]). The BASDAI increased from a mean ± SD of 3.8 ± 2.0 at baseline to 4.3 ± 2.1 at 6 months (difference of +0.5 [95% CI 0.1, 0.9]). The CRP levels, infliximab trough levels, and anti-infliximab antibody levels did not change. Just prior to CT-P13 discontinuation, the DAS28-CRP components tender joint count and patient's global assessment of disease activity, as well as the BASDAI were increased compared to baseline. The most frequently reported AEs were arthralgia, fatigue, pruritus, and myalgia. A shorter REM infusion interval (hazard ratio: 0.77 [95% CI 0.62, 0.95]) at baseline was predictive of discontinuing CT-P13. CONCLUSION: In our cohort, one-fourth of patients discontinued CT-P13 during 6 months of follow-up, mainly due to an increase in the subjective features of the tender joint count and the patient's global assessment of disease activity and/or subjective AEs, possibly explained by nocebo effects and/or incorrect causal attribution effects.

Optimizing the expediency of TNFi in rheumatoid arthritis: offering a TNFi holiday in patients having reached low-disease activity in the maintenance phase.

INTRODUCTION: The treatment of rheumatoid arthritis (RA) has been revolutionized since the introduction of biological disease-modifying antirheumatic drugs such as tumour necrosis factor alpha inhibitors (TNFi), and clinical remission has become a realistic target in the treatment strategy. Discontinuation strategies of TNFi therapy after reaching sustained remission or low-disease activity (LDA) have been emerging. These strategies are important considering the risk-benefit profile of TNFi, as well as looking at them from a cost-economic point of view. AREAS COVERED: This article presents an overview of recent major studies on TNFi withdrawal, and tapering and about the safety of doing so. EXPERT OPINION: Although data are still limited, tapering or discontinuing TNFi in some RA patients may well be possible, especially in the early RA patients who are methotrexate naive. Also, a substantial group of longer established RA patients can stop or taper TNFi, particularly when ultrasonography signals are negative. However, before making the decision of implementing it in the routine care for RA patients, more predictors for successful discontinuation are desired.