Interactions between rheumatoid arthritis antibodies are associated with the response to anti-tumor necrosis factor therapy

Towards Personalized Medicine in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, incurable, multisystem, inflammatory disease characterized by synovitis and extra-articular features. Although several advanced therapies targeting inflammatory mechanisms underlying the disease are available, no advanced therapy is universally effective. Therefore, a ceiling of treatment response is currently accepted where no advanced therapy is superior to another. The current challenge for medical research is the discovery and integration of predictive markers of drug response that can be used to personalize medicine so that the patient is started on "the right drug at the right time". This review article summarizes our current understanding of predicting response to anti-rheumatic drugs in RA, obstacles impeding the development of personalized medicine approaches and future research priorities to overcome these barriers.

Rheumatoid factor titers, but not Fc fragments, may be strongly associated with drug survival of anti-TNF agents in patients with rheumatoid arthritis

OBJECTIVE

To investigate the effects of both the Fc fragment in tumor necrosis factor (TNF) inhibitors and rheumatoid factor (RF) titers on treatment survival, disease activity, and laboratory parameters in patients with rheumatoid arthritis (RA).

METHODS

In this retrospective cohort study, patients with RA who had started any anti-TNF therapy between January 2017 and March 2020 and who had stayed on this treatment for at least six months were included. The data of the patients were compared separately according to continuation or discontinuation of treatment and the presence or absence of Fc portion in the structure of anti-TNFs. Patients who were taking certolizumab pegol (CZP) without the Fc fragment were placed in the "without Fc group" (wo/Fc), while patients who were taking other drugs (adalimumab, etanercept, golimumab, and infliximab) were placed in the "with Fc group" (w/Fc).

RESULTS

Among the 221 RA patients whose data were available, 52 patients met the inclusion criteria and were included in the study. There was a significant difference in the DAS28-CRP score between wo/Fc group and w/Fc group in the third month of treatment (p=0.012). However, this difference did not persist at the sixth month of treatment (p=0.384). According to the cox-regression results, RF titers were determined to have a significant impact on the drug survival of anti-TNF agents when adjustments were made for the effects of other candidate predictors (Hazard ratio: 1.007 (1.002-1.012), p=0.009).

CONCLUSION

Our results suggest that compared to the Fc fragment, RF titers were the more important risk factor in survival of anti-TNF drugs.

Tailored therapeutic decision of rheumatoid arthritis using proteomic strategies: how to start and when to stop?

Unpredictable treatment responses have been an obstacle for the successful management of rheumatoid arthritis. Although numerous serum proteins have been proposed, there is a lack of integrative survey to compare their relevance in predicting treatment outcomes in rheumatoid arthritis. Also, little is known about their applications in various treatment stages, such as dose modification, drug switching or withdrawal. Here we present an in-depth exploration of the potential usefulness of serum proteins in clinical decision-making and unveil the spectrum of immunopathology underlying responders to different drugs. Patients with robust autoimmunity and inflammation are more responsive to biological treatments and prone to relapse during treatment de-escalation. Moreover, the concentration changes of serum proteins at the beginning of the treatments possibly assist early recognition of treatment responders. With a better understanding of the relationship between the serum proteome and treatment responses, personalized medicine in rheumatoid arthritis will be more achievable in the near future.

An assessment of serum interleukin - 39 in rheumatoid arthritis patients from Iraq

Introduction and Aim: The pro-inflammatory cytokine IL-39, a member of the IL-12 family plays a key role in the inflammatory response by modulating immune cell activity and inflammation. A literature search shows no study undertaken for the effect of IL-39's on arthritis so far. Hence, the purpose of this study was to investigate the role of IL-39 in rheumatoid arthritis. Materials and Methods: This study involved 80 patients with rheumatoid arthritis registered at the Rheumatology Clinic at Baghdad teaching hospital. The patients were divided into three groups based on treatments received. Group 1 included patients who were not on any treatment for arthritis, Group 2 with patients on hydroxychloroquine and or prednisone treatment, and Group 3 that received Enbrel® (etanercept) and HUMIRA® (adalimumab) treatment for rheumatoid arthritis. A control group was included in the study. Patients in all groups were assessed for their serum IL-39 concentration, C - reactive protein, Anti-cyclic citrullinated peptide antibody (ACCP) and ESR.  Results: The patient age and BMI were not significantly different between the groups receiving treatment for Rheumatoid arthritis. A significant increase in the interleukin 39 concentration was observed in treatment groups (G1, G2, G3) as compared to normal healthy controls regardless of whether they were positive or negative for the anti-CCP test. Conclusion: This study showed that the serum interleukin IL-39 levels significantly increased in patients diagnosed with rheumatoid arthritis thus suggesting that IL-39 could be considered as a potential inflammatory biomarker of RA.

Differential efficacy of TNF inhibitors with or without the immunoglobulin fragment crystallizable (Fc) portion in rheumatoid arthritis: the ANSWER cohort study

Rheumatoid factor (RF) binds to the fragment crystallizable (Fc) portion of immunoglobulin. It could bind to the Fc portion of anti-TNF inhibitors (TNFi) and attenuate the clinical efficacy. We tried to determine whether the therapeutic efficacy of TNFi with Fc might be lower than that of TNFi without Fc in rheumatoid arthritis (RA) patients with high titres of RF. The Kansai Consortium for Well-being of Rheumatic Disease Patients (ANSWER) cohort is an observational multi-center registry of patients with RA in the Kansai district of Japan. RA patients treated with TNFi were included and divided into two groups based on the structural characteristics between TNFi with Fc (infliximab, adalimumab, golimumab, and etanercept) and TNFi without Fc (certolizumab pegol). Patients were classified into 4 groups according to RF titre quartiles. The sequential disease activity score in 28 joints using erythrocyte sedimentation rate (DAS28-ESR) was compared by Mann-Whitney U test between TNFi with and without Fc in each RF titre group. Multiple linear regression analysis was used to analyze the effect of TNFi without Fc for the change of DAS28-ESR adjusted after potential confounders. A total of 705 RA patients were classified into four groups (RF¹; RF 0-15.0 IU/mL, RF²; 15.0-55.0, RF³; 55.0-166, RF⁴; 166-7555). In RF⁴, RA patients treated with TNFi without Fc had a significantly lower DAS28-ESR than those treated with TNFi with Fc [3.2 (2.3-4.2) vs. 2.7 (2.0-3.0)] after 12 months. This effect of TNFi without Fc for the change of DAS28-ESR after 12 months treatment retained in multivariate analysis in RF⁴. TNFi without Fc may be more efficacious than TNFi with Fc in RA patients with high RF titres.