Management of patients with inflammatory rheumatic diseases after treatment failure with a first tumour necrosis factor inhibitor: A narrative review

The emergence of biologics with different modes of action (MoAs) and therapeutic targets has changed treatment patterns in patients with inflammatory rheumatic diseases. While tumour necrosis factor inhibitors (TNFis) are often utilized as the first biologic disease-modifying antirheumatic drug, some patients may not respond adequately (primary failure), fail to sustain response over time (secondary failure), or experience intolerable adverse events. Whether these patients would benefit more from cycling to a different TNFi or switching to a biologic with a different MoA is still unclear. We discuss here treatment outcomes of TNFi cycling versus MoA switching after treatment failure with a first TNFi in patients with inflammatory rheumatic diseases, focusing specifically on rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis, and juvenile idiopathic arthritis. Treatment guidelines for these patients are ambiguous and, at times, contradictory in their recommendations. However, this is due to a lack of high-quality head-to-head data to definitively support cycling between TNFis after failure to a first-line TNFi over switching to a different MoA.

Identifying Predictors of First-Line Subcutaneous TNF-Inhibitor Persistence in Patients with Inflammatory Arthritis: A Decision Tree Analysis by Indication

INTRODUCTION

Treatment persistence is a proxy for efficacy, safety and patient satisfaction, and a switch in treatment or treatment discontinuation has been associated with increased indirect and direct costs in inflammatory arthritis (IA). Hence, there are both clinical and economic incentives for the identification of factors associated with treatment persistence. Until now, studies have mainly leveraged traditional regression analysis, but it has been suggested that novel approaches, such as statistical learning techniques, may improve our understanding of factors related to treatment persistence. Therefore, we set up a study using nationwide Swedish high-coverage administrative register data with the objective to identify patient groups with distinct persistence of subcutaneous tumor necrosis factor inhibitor (SC-TNFi) treatment in IA, using recursive partitioning, a statistical learning algorithm.

METHODS

IA was defined as a diagnosis of rheumatic arthritis (RA), ankylosing spondylitis/unspecified spondyloarthritis (AS/uSpA) or psoriatic arthritis (PsA). Adult swedish biologic-naïve patients with IA initiating biologic treatment with a SC-TNFi (adalimumab, etanercept, certolizumab or golimumab) between May 6, 2010, and December 31, 2017. Treatment persistence of SC-TNFi was derived based on prescription data and a defined standard daily dose. Patient characteristics, including age, sex, number of health care contacts, comorbidities and treatment, were collected at treatment initiation and 12 months before treatment initiation. Based on these characteristics, we used recursive partitioning in a conditional inference framework to identify patient groups with distinct SC-TNFi treatment persistence by IA diagnosis.

RESULTS

A total of 13,913 patients were included. Approximately 50% had RA, while 27% and 23% had AS/uSpA and PsA, respectively. The recursive partitioning algorithm identified sex and treatment as factors associated with SC-TNFi treatment persistence in PsA and AS/uSpA. Time on treatment in the groups with the lowest treatment persistence was similar across all three indications (9.5-11.3 months), whereas there was more variation in time on treatment across the groups with the highest treatment persistence (18.4-48.9 months).

CONCLUSIONS

Women have low SC-TNFi treatment persistence in PsA and AS/uSpA whereas male sex and golimumab are associated with high treatment persistence in these indications. The factors associated with treatment persistence in RA were less distinct but may comprise disease activity and concurrent conventional systemic disease-modifying anti-rheumatic drug (DMARD) treatment.

Biological Agent Switching in Patients With Juvenile Idiopathic Arthritis: A Tertiary Center Experience

OBJECTIVE

The purpose of this study is to investigate the causes and outcomes of switching biological agents in juvenile idiopathic arthritis (JIA) patients using biological agents and compare the characteristics of patients whose biological agents are switched and those whose are not.

METHODS

This medical records review study was conducted with 128 patients who were diagnosed with JIA at our clinic between January 2009 and January 2022 and were receiving biologic agents. Factors affecting the biologic agent switching were investigated.

RESULTS

The JIA subtype with the most frequent switching in biological agents was systemic JIA (n = 13, 40.6%). Systemic JIA was followed by rheumatoid factor-negative polyarticular JIA and persistent oligoarticular JIA with 5 patients (15.6%), extended oligoarticular JIA and enthesitis-related JIA with 3 patients (9.3%), rheumatoid factor-positive polyarticular JIA with 2 patients (6.2%), and undifferentiated JIA with 1 patient (3.1%). Among the patients, 32 (25%) patients had their biological agent switched once, and 5 (3.9%) had theirs switched twice. The most frequently used biological agent was etanercept (n = 76, 59.3%), whereas the most frequently observed cases of biological agent switching were from an anti-TNF agent to another anti-TNF agent (40.6%). The reason for switching was unresponsiveness to the agent in 22 patients (68.8%), adverse effects in 6 patients (18.7%), drug intolerance in 1 patient (3.1%), and other reasons in 3 patients (9.3%).

CONCLUSIONS

The most frequently used biological agent was etanercept; the most frequent cases of biological agents switching were from an anti-TNF agent to another anti-TNF agent.

The second decade of anti-TNF-a therapy in clinical practice: new lessons and future directions in the COVID-19 era

Since the late 1990s, tumor necrosis factor alpha (TNF-α) inhibitors (anti-TNFs) have revolutionized the therapy of immune-mediated inflammatory diseases (IMIDs) affecting the gut, joints, skin and eyes. Although the therapeutic armamentarium in IMIDs is being constantly expanded, anti-TNFs remain the cornerstone of their treatment. During the second decade of their application in clinical practice, a large body of additional knowledge has accumulated regarding various aspects of anti-TNF-α therapy, whereas new indications have been added. Recent experimental studies have shown that anti-TNFs exert their beneficial effects not only by restoring aberrant TNF-mediated immune mechanisms, but also by de-activating pathogenic fibroblast-like mesenchymal cells. Real-world data on millions of patients further confirmed the remarkable efficacy of anti-TNFs. It is now clear that anti-TNFs alter the physical course of inflammatory arthritis and inflammatory bowel disease, leading to inhibition of local and systemic bone loss and to a decline in the number of surgeries for disease-related complications, while anti-TNFs improve morbidity and mortality, acting beneficially also on cardiovascular comorbidities. On the other hand, no new safety signals emerged, whereas anti-TNF-α safety in pregnancy and amid the COVID-19 pandemic was confirmed. The use of biosimilars was associated with cost reductions making anti-TNFs more widely available. Moreover, the current implementation of the “treat-to-target” approach and treatment de-escalation strategies of IMIDs were based on anti-TNFs. An intensive search to discover biomarkers to optimize response to anti-TNF-α treatment is currently ongoing. Finally, selective targeting of TNF-α receptors, new forms of anti-TNFs and combinations with other agents, are being tested in clinical trials and will probably expand the spectrum of TNF-α inhibition as a therapeutic strategy for IMIDs.

[Innovative strategies for treatment of rheumatoid arthritis]

Besides excellent guidelines and newly developed highly effective drugs, evidence-based strategic use of these new drugs has especially contributed to enormous advances in rheumatoid arthritis treatment, apparent especially since 2000. Currently, the treat-to-target (T2T) strategy has proven to be the most successful in several studies and systematic reviews. The target is to achieve remission, which should be reached and sustained for an optimal outcome (i.e. stable over a long time period). If the initial disease-modifying antirheumatic drug (DMARD) treatment fails, the best strategy for continuing treatment is controversial, with swap or switch being open to debate (change within a class of drugs or change in the mechanism of action). Recent studies seem to indicate that switching to another mechanism of action is the most successful approach. A hotly discussed topic is the question whether DMARD treatment can or should be tapered when sustained remission has been achieved? Many patients wish for a reduction of drugs in cases of stable remission; however, the stable disease control might become destabilized by tapering. The main priority is the reduction or tapering of glucocorticoid treatment. When the decision for reduction of DMARD treatment is made together with the patient, a complete cessation bears a high risk of a flare, therefore, a careful step by step reduction of DMARD treatment should be preferred. In the case of a running combination, the question whether the conventional DMARD (mostly methotrexate), the biological (b)DMARD or targeted synthetic (ts)DMARD should be reduced first, must be decided on an individual basis. Most patients prefer to first reduce methotrexate and transfer to a monotherapy.

Changes in the use patterns of bDMARDs in patients with rheumatic diseases over the past 13 years

The better understanding of the safety of biologic DMARDs (bDMARDs), as well as the emergence of new bDMARDs against different therapeutic targets and biosimilars have likely influenced the use patterns of these compounds over time. The aim of this study is to assess changes in demographic characteristics, disease activity and treatment patterns in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), or ankylosing spondylitis (AS) who started a first- or second-line biologic between 2007 and mid-2020. Patients diagnosed with RA, PsA or AS included in the BIOBADASER registry from January 2007 to July 2020 were included. According to the start date of a first- or second-line biologic therapy, patients were stratified into four time periods: 2007-2009; 2010-2013; 2014-2017; 2018-2020 and analyzed cross-sectionally in each period. Demographic and clinical variables, as well as the type of biologic used, were assessed. Generalized linear models were applied to study the evolution of the variables of interest over time periods, the diagnosis, and the interactions between them. A total of 4543 patients initiated a first biologic during the entire time frame of the study. Over the four time periods, disease evolution at the time of biologic initiation (p < 0.001), disease activity (p < 0.001), retention rate (p < 0.001) and the use of tumor necrosis factor inhibitors as a first-line treatment (p < 0.001) showed a significant tendency to decrease. Conversely, comorbidities, as assessed by the Charlson index (p < 0.001), and the percentage of patients using bDMARDs in monotherapy (p < 0.001), and corticosteroids (p < 0.001) tended to increase over time. Over the entire period of the study's analysis, 3289 patients started a second biologic. The following trends were observed: decreased DAS28 at switching (p < 0.001), lower retention rates (p = 0.004), and incremental changes to the therapeutic target between the first and second biologic (p < 0.001). From 2007 until now rheumatic patients who started a biologic were older, exhibited less clinical activity, presented more comorbidities, and switched to a different biologic more frequently and earlier.

Association of first, second, and third-line bDMARDs and tsDMARD with drug survival among seropositive rheumatoid arthritis patients: Cohort study in A real world setting

OBJECTIVES

To determine the association of first, second, and third-line biologic disease-modifying antirheumatic drugs (bDMARDs) and tofacitinib with drug survival among seropositive rheumatoid arthritis (RA) patients.

METHODS

The study population was composed of 8,018 seropositive RA patients who were prescribed bDMARDs or tofacitinib between January 2014 and January 2019 from the Korean Health Insurance Review and Assessment Service database. First, second, and third-line choice of tumor necrosis factor inhibitors (TNFi) including etanercept, infliximab, adalimumab, and golimumab, as well as non-TNFi including tocilizumab, rituximab, tofacitinib, and abatacept were assessed. Multivariate Cox proportional hazards regression was used to determine the adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for drug failure according to bDMARD or tofacitinib choice starting from the initial prescription date.

RESULTS

Compared to first etanercept users, patients with first tocilizumab (aHR 0.56, 95% CI 0.46-0.68), tofacitinib (aHR 0.27, 95% CI 0.18-0.42), or abatacept (aHR 0.83, 95% CI 0.69-0.99) had lower risk of drug failure. Second choice of tocilizumab (aHR 0.38, 95% CI 0.25-0.55), tofacitinib (aHR 0.23, 95% CI 0.15-0.37), or abatacept (aHR 0.54, 95% CI 0.35-0.84) was associated with lower drug failure risk compared to second etanercept users. Finally, third choice of tocilizumab (aHR 0.32, 95% CI 0.16-0.62) or tofacitinib (aHR 0.35, 95% CI 0.19-0.63) was associated with lower drug failure risk compared to third TNFi users.

CONCLUSION

First and second-line tocilizumab, tofacitinib, or abatacept may lead to improved drug survival. Third-line use of tocilizumab or tofacitinib may be beneficiary in reducing drug failure risk among seropositive RA patients.

Retention rate of a second line with a biologic DMARD after failure of a first-line therapy with abatacept, tocilizumab, or rituximab: results from the Italian GISEA registry

OBJECTIVES

EULAR recommendations do not suggest which biologic disease-modifying anti-rheumatic drug (bDMARD) should be preferred after failure of a first bDMARD in the treatment of rheumatoid arthritis (RA). In particular, few data are available regarding the effectiveness of a second-line bDMARD after failure of abatacept (ABA), tocilizumab (TCZ), and rituximab (RTX). The aim of this study was to analyze the retention rate of a second line with tumor necrosis factor inhibitors (TNFi) or other mechanisms of action (MoAs), after the failure of either RTX, TCZ, or ABA.

METHODS

Two hundred and seventy-eight RA patients from the Italian GISEA registry were included in the study. RTX was the first bDMARD in 18% of patients, ABA in 45.7%, and TCZ in 36.3%, while the second bDMARD was a TNFi (group 1) in 129 patients and an agent with a different MoA (group 2) in 149.

RESULTS

During a median follow-up of 22 months (IQR 68), 129 patients discontinued their treatment; patients of group 1 discontinued the treatment more frequently than patients of group 2 (p<0.001) with retention rates of 33.6±5.7% and 63.6±4.6% after 104 weeks for group 1 and group 2, respectively (p<0.001). At multivariate analysis, the mechanism of action was the only predictor for the maintenance in therapy.

CONCLUSIONS

According to our data, ABA, RTX, and TCZ seem to maintain a good retention rate also when used as a second-line therapy, suggesting their use after the failure of a non-TNFi as first-line therapy. However, specifically designed studies are needed to evaluate the more appropriate therapeutic strategies in RA, according to the first-line drug, including new targeted synthetic DMARDs. Key Points • A large proportion of rheumatoid arthritis patients fail the first biologic DMARD. • Few data are available about the efficacy of biologic DMARD after the failure of a non-TNF inhibitor. • Abatacept, rituximab, or tocilizumab seem to maintain a good retention rate after the failure of a first-course therapy with a non-TNF inhibitor.

Approach to switching biologics in juvenile idiopathic arthritis: a real-life experience

The primary aim of the treatment of juvenile idiopathic arthritis (JIA) is complete remission and minimizing the development of complications. Though biologic agents (BAs) provide better disease control, data related to BA switching patterns in JIA patients are scarce. This study aimed to determine the BA switching patterns in JIA patients. The study included children with JIA that received ≥ 1 BAs. Disease activity was evaluated based on the juvenile arthritis disease activity score 71 (JADAS71). Demographic data, clinical and laboratory findings, BA switching patterns, and the rationales for BA switching were recorded. The study included 177 (82 female and 95 male) JIA patients that received ≥ 1 BAs. Mean age at diagnosis of JIA was 9.1 ± 4.9 years. BAs were prescribed a median of 14 months (range: 3-66 months) after diagnosis. Among the 177 patients, 31 (17.5%) required BA switching a median 10.5 months (range: 3-38 months) after initiation of the first BA. Among all the BAs that were switched to after administration of the first BA, tocilizumab was the most commonly switched (n = 15). The most common reason for BA switching was inadequate response (n = 29). BAs were switched 2 times in 5 patients and 3 times in 1 patient. When patients that switched BAs 1 time were compared to those that switched 2 and 3 times there were not any differences in terms of JIA types, whereas those that switched 2 and 3 times had a higher active joint count and JADAS71 score after 6 months of initiation of the first BA. As some of the JIA patients could not achieve remission despite using the prescribed BA, BA switching was required. Herein, we provide data on both BA switching patterns and requirements, which may improve the management of JIA patients.

Cost-utility analysis of second-line therapy with rituximab compared to tumour necrosis factor inhibitors in rheumatoid arthritis

OBJECTIVE

To compare direct costs and treatment utility associated with the second-line therapy with rituximab and tumour necrosis factor inhibitors (TNFis) (adalimumab, etanercept, and infliximab) in patients with Rheumatoid Arthritis (RA) using data from a prospective registry.

METHODS

Health Assessment Questionnaire Disability Index (HAQ-DI) scores and RA-related healthcare resource utilization data (biologic agents and visits to rheumatologists) were extracted from a registry (Quebec, Canada) for patients with RA (n = 129) who had to discontinue a first-line TNFi and were treated with rituximab, adalimumab, etanercept, or infliximab as the second-line therapy between January 2007 and May 2016. A decision analytic model followed patients for 1 and 6 years. Treatment utility was measured as quality-adjusted life-years (QALYs) gained, which were calculated from HAQ-DI scores observed over the follow-up time. Quebec 2020 unit costs (Canadian Dollars, $) were used to value healthcare resource consumption. A probabilistic sensitivity analysis was performed with 10,000 Monte Carlo simulations to assess uncertainty around point-estimates of cost-utility.

RESULTS

Over 1-year, rituximab and etanercept resulted in the effectiveness of 0.80 QALYs gained at the cost of $14,291and $18,880, respectively, and were dominant (i.e. associated with lower costs and more QALYs gained) compared to adalimumab (0.79 QALYs, $18,825) and infliximab (0.76 QALYs, $20,158). Over 6-years, rituximab (4.42 QALYs, $82,402) was dominant compared to adalimumab (4.30 QALYs, $101,420), etanercept (4.02 QALYs, $99,191), and infliximab (3.71 QALYs, $100,396). In the probabilistic analysis, rituximab was dominant over adalimumab, etanercept, and infliximab with the probability of 0.51, 0.62, and 0.65, respectively.

CONCLUSION

Real-world data revealed differences between alternative biologic agents used as the second-line therapy in terms of both treatment costs for the healthcare system and utility of treatment for patients. Therefore, new guidelines on the order of selecting and switching biologic agents should be explored.

Understanding the Role of Interleukin-6 (IL-6) in the Joint and Beyond: A Comprehensive Review of IL-6 Inhibition for the Management of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, debilitating autoimmune disorder involving inflammation and progressive destruction of the joints, affecting up to 1% of the population. The majority of patients with RA have one or more comorbid conditions, the most common being cardiovascular disease, osteoporosis, and depression, the presence of which are associated with poorer clinical outcomes and lower health-related quality of life. RA pathogenesis is driven by a complex network of proinflammatory cells and cytokines, and of these, interleukin-6 (IL-6) plays a key role in the chronic inflammation associated with RA. Through cell signaling that can be initiated by both membrane-bound and soluble forms of its receptor, IL-6 acts both locally to promote joint inflammation and destruction, and in the circulation to mediate extra-articular manifestations of RA, including pain, fatigue, morning stiffness, anemia, and weight loss. This narrative review describes the role of IL-6 in the pathogenesis of RA, its comorbidities, and extra-articular systemic manifestations, and examines the effects of the IL-6 receptor inhibitors sarilumab and tocilizumab on clinical endpoints of RA, patient-reported outcomes, and common comorbidities and extra-articular manifestations.

Golimumab effectiveness in biologic inadequate responding patients with rheumatoid arthritis, psoriatic arthritis and spondyloarthritis in real-life from the Italian registry GISEA

OBJECTIVE

To evaluate the clinical effectiveness of golimumab in biologic inadequate responder (IR) patients with Rheumatoid arthritis (RA), Spondyloarthritis (SpA), and Psoriatic arthritis (PsA).

METHODS

We analyzed 1424 patients on golimumab from the GISEA registry. Drug survival was estimated by Kaplan-Meier analysis in biologic-naïve, 1-biologic IR, ≥2-biologics IR patients. Hazard ratios (HRs) of discontinuing golimumab at 2 years were assessed by multivariate Cox regression. Patients achieving CDAI based low disease activity (LDA) or BASDAI<4 were calculated at 6 and 12 months.

RESULTS

In RA (n.370), the 2-years survival on golimumab was 61.4% in 1-biologic IR, 51.9% in≥2-biologics IR, and 73.1% in biologic-naive patients (P=0.002 vs≥2-biologics IR). In SpA (n.502), the survival was similar among 1-biologic IR (80%), ≥2-biologics IR (76.5%), and biologic-naive (74.6%) patients (P>0.05). In PsA (n.552) the survival was 72% in 1-biologic IR, 72.5% in≥2-biologics IR, and 71.8% in naïve-biologic (P>0.05). Predictors of golimumab discontinuation were monotherapy (HR 1.65) for RA, female gender for SpA (HR 2.48) and PsA (HR 1.57). In RA, patients on CDAI-LDA were lower in 1-biologic IR (40%) or≥2 biologics IR (40%) than in biologic-naïve (60%) group at 6 months (P=0.02), but no difference was observed at 12 months. In PsA and SpA, the percentage of patients on CDAI-LDA or BASDAI<4 at 6 months was almost identical across the subgroups.

CONCLUSIONS

Golimumab had similar effectiveness in biologic-failure and biologic-naïve SpA and PsA, but seems to be less effective in multi-failure RA patients, especially as monotherapy. The best outcomes were seen in male patients.

Targeting Granulocyte-Monocyte Colony-Stimulating Factor Signaling in Rheumatoid Arthritis: Future Prospects

Rheumatoid arthritis (RA) is a systemic, autoimmune disease that affects joints and extra-articular structures. In the last decade, the management of this chronic disease has dramatically changed with the introduction of several targeted mechanisms of action, such as tumor necrosis factor-α inhibition, T-cell costimulation inhibition, B-cell depletion, interleukin-6 blockade, and Janus kinase inhibition. Beyond its well-known hematopoietic role on the proliferation and differentiation of myeloid cells, granulocyte-monocyte colony-stimulating factor (GM-CSF) is a proinflammatory mediator acting as a cytokine, with a proven pathogenetic role in autoimmune disorders such as RA. In vitro studies clearly demonstrated the effect of GM-CSF in the communication between resident tissue cells and activated macrophages at chronic inflammation sites, and confirmed the elevation of GM-CSF levels in inflamed synovial tissue of RA subjects compared with healthy controls. Moreover, a pivotal role of GM-CSF in the perception of pain has been clearly confirmed. Therefore, blockade of the GM-CSF pathway by monoclonal antibodies directed against the cytokine itself or its receptor has been investigated in refractory RA patients. Overall, the safety profile of GM-CSF inhibitors seems to be very favorable, with a particularly low incidence of infectious complications. The efficacy of this new mechanism of action is comparable with main competitors, even though the response rates reported in phase II randomized controlled trials (RCTs) appear to be numerically lower than the response rates observed with other biological disease-modifying antirheumatic drugs already licensed for RA. Mainly because of this reason, nowadays the development program of most GM-CSF blockers for RA has been discontinued, with the exception of otilimab, which is under evaluation in two phase III RCTs with a head-to head non-inferiority design against tofacitinib. These studies will likely be useful for better defining the potential role of GM-CSF inhibition in the therapeutic algorithm of RA. On the other hand, the potential role of GM-CSF blockade in the treatment of other rheumatic diseases is now under investigation. Phase II trials are ongoing with the aim of evaluating mavrilimumab for the treatment of giant cell arteritis, and namilumab for the treatment of spondyloarthritis. Moreover, GM-CSF inhibitors have been tested in osteoarthritis and diffuse subtype of systemic sclerosis. This review aims to describe in detail the available evidence on the GM-CSF blocking pathway in RA management, paving the way to a possible alternative treatment for RA patients. Novel insights regarding the potential use of GM-CSF blockers for alternative indications will be also addressed.

Real-World Patient Experience of Switching Biologic Treatment in Inflammatory Arthritis and Ulcerative Colitis - A Systematic Literature Review

PURPOSE

To obtain an up-to-date overview of the measurement of patient experience of switching biologic treatment in patients with inflammatory arthritis (IA) or ulcerative colitis (UC). Secondary objectives included summarizing the types of patient-reported outcomes (PROs) used (if any), and related findings; and summarizing medical and non-medical reasons for treatment switch and/or discontinuation.

METHODS

A systematic literature review (SLR) was performed, searching Medline and Embase for relevant publications.

RESULTS

In total, 70 relevant publications were identified. While the majority of these reported reasons for switching and/or discontinuing treatment, only four provided information explicitly regarding patient-reported experience of switching biologic treatment. All four utilized ranking tools to assess patient experience of switching biologic treatment. The most common reason for switching and/or discontinuing treatment was loss of efficacy, while the least common reason was patient preference.

CONCLUSION

Although the number of available treatments in IA and UC have increased, there is a sparsity of information regarding patient-reported experience of switching biologic treatment. Further research regarding patient preference and/or experience would benefit this therapeutic area and help guide treatment choices.

The Giants (biologicals) against the Pigmies (small molecules), pros and cons of two different approaches to the disease modifying treatment in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that, if untreated, can lead to disability and reduce the life expectancy of affected patients. Over the last two decades the improvement of knowledge of the pathogenetic mechanisms leading to the development of the disease has profoundly changed the treatment strategies of RA through the development of biotechnological drugs (bDMARDs) directed towards specific pro-inflammatory targets involved in the RA network. To date, the therapeutic armamentarium for RA includes ten bDMARDs able to produce the depletion B-cells, the blockade of three different pro-inflammatory cytokines (tumour necrosis factor alpha, interleukin-6 and interleukin-1), or the inhibition of T-cell co-stimulation. The introduction of these new compounds has dramatically improved outcomes in the short and long term, although still a significant proportion of patients are unable to reach or maintain the treatment target over time. The identification of the fundamental role of Janus kinases in the process of transduction of the inflammatory signal within the immune cells has recently provided the opportunity to use the new pharmacological class of small molecules for the therapy of RA, further increasing the number of treatment options. In this review the PROS and CONS of these two drug classes will be discussed, trying to provide the evidence currently available to make the right choice based on the analysis of the efficacy and safety profile of the different drugs on the market and close to marketing.

Upadacitinib and filgotinib: the role of JAK1 selective inhibition in the treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease characterized by joint involvement, extra-articular manifestations, comorbidities, and increased mortality. In the last few decades, the management of RA has been dramatically improved by the introduction of a treat-to-target approach aiming to prevent joint damage progression. Moreover, the increasing knowledge about disease pathogenesis allowed the development of a new drug class of biologic agents targeted on immune cells and proinflammatory cytokines involved in RA network. Despite the introduction of several targeted drugs, a significant proportion of RA patients still fail to achieve the clinical target; so, more recently the focus of research has been shifted toward the inhibition of kinases involved in the transduction of the inflammatory signal into immune cells. In particular, two Janus kinase (JAK) inhibitors, baricitinib and tofacitinib, have been licensed for the treatment of RA as a consequence of a very favorable profile observed in randomized controlled trials (RCTs) conducted across different RA subpopulations. Both these new compounds are active on the majority of four JAK family members (JAK1, JAK2, JAK3, and TYK2), whereas the most recent emerging approach is directed toward the development of JAK1 selective inhibitors (upadacitinib and filgotinib) with the aim to improve the safety profile by minimizing the effects on JAK3 and, especially, JAK2. In this narrative review, we discuss the rationale for JAK inhibition in RA, with a special focus on the role of JAK1 selective blockade and a detailed description of available data from the results of clinical trials on upadacitinib and filgotinib.

Mavrilimumab: a unique insight and update on the current status in the treatment of rheumatoid arthritis

Introduction: Rheumatoid arthritis (RA) is a chronic, systemic, autoimmune disease, which affects joints and extra-articular structures. Nowadays, the armamentarium of therapeutic options is progressively expanding and embraces several mechanisms of action: TNF inhibition, B-cell depletion, T-cell co-stimulation inhibition, IL-6 blockade, and JAK-inhibition. Granulocyte-Monocyte-Colony-Stimulating-Factor (GM-CSF) is a mediator acting as a cytokine with a proven pathogenetic role in RA, providing a potential alternative target for the management of the disease. Mavrilimumab is a monoclonal antibody against GM-CSF receptor, which has been successfully tested in RA patients. Areas covered: Beginning with a description of the preclinical evidence and the rationale for GM-CSF blockade in RA, this review will provide a wide overview of mavrilimumab efficacy and safety profile by analyzing phase I/II RCTs conducted in patients with moderate to severe RA. Expert opinion: According to the promising results from phase I-II RCTs, mavrilimumab could be considered as an additional therapeutic option for RA patients multi-resistant to the available targeted drugs. However, the optimal dose and the profile of this new drug should be confirmed in phase III RCTs before the marketing.

Systemic rheumatic diseases: From biological agents to small molecules

The development of biologics and small oral molecules has recently changed the scenario of pharmacologic treatment of systemic rheumatic diseases and it has become a real revolution. These drugs have innovative mechanisms of action, based on the inhibition of specific molecular or cellular targets directly involved in disease pathogenesis. This new scenario has lead to a regular update of the management recommendations of several institutions, such as those for Rheumatoid Arthritis treatment that address the use of conventional and biologic therapies including TNF inhibitors (adalimumab, certolizumab pegol, etanercept, golimumab, infliximab), abatacept, rituximab, IL-6 inhibitors (tocilizumab and sarilumab), biosimilars and small oral molecules (the JAK inhibitors tofacitinib and baricitinib). Monotherapy, combination therapy, treatment strategies (such as treat-to-target) and the targets of sustained clinical remission or low disease activity are the final goal of the guidelines for rheumatic patients management. In another condition represented by Axial Spondyloarthritis guidelines suggest to start first with non-steroidal anti-inflammatory drugs to improve lifestyle and reduce spine inflammation, but if this is not achieved in 2-4 weeks it is important to consider the use of local therapies (i.e. glucocorticoid injections) or to start biologic therapy such as TNF inhibitors and then eventually switching to another TNF inhibitor or swapping to IL-17 inhibitor. In the case of active Psoriatic Arthritis, guidelines suggest to start with non-steroidal anti-inflammatory drugs and even local glucocorticoid injections especially for oligoarthritis, then to start conventional therapies if lack of efficacy, and finally start biologics or small oral molecules in the presence of drugs toxicity, unfavorable prognostic factors and still active arthritis. In several cases, active Psoriatic Arthritis patients develop a complex clinical condition with comorbidities such as diabetes, inflammatory bowel disease and high risk of infections, and for this reason the American College of Rheumatology and the National Psoriasis Foundation have developed specific guidelines for their management. Biologic and new small molecules therapies are very expensive, but the availability of biosimilars offers the opportunity of reducing the treatment cost and significantly decreasing the cost of originators as well. In fact, we live in a period characterized by the need to rationalize costs of these drugs, to allow treating a higher number of patients and to maintain a homogeneous possibility of treatment choice. For these reasons, we need to follow scientific guidelines and patients' clinical conditions to choose the correct treatment, also based on the economic burden of therapies.

Useful message in choosing optimal biological agents for patients with autoimmune arthritis

The introduction of biological disease-modifying antirheumatic drug (bDMARD) treatments for various types of autoimmune arthritis, such as rheumatoid arthritis, psoriatic arthropathy and ankylosing spondylitis, represents a new era of treatment for patients with a refractory response to conventional synthetic DMARDs (csDMARDs). Many new bDMARDs with different modalities or that target different pro-inflammatory molecules, likely cytokines, are rapidly emerging. Hence, physicians in the field may be confused about choosing appropriate bDMARDs for their patients. Considering the high cost of bDMARDs and the rapid destructive process of autoimmune arthritis in patients, the choice of optimal bDMARDs for patients who fail to respond or show an inadequate therapeutic response to csDMARDs designed to control the disease is very critical. Here, we summarize the strengths and weaknesses of bDMARDs and specifically focus on their uses in patients with comorbid conditions or with specific medical conditions, such as pregnancy. This commentary provides a solid up-to-date review on commercially available bDMARDs and very useful information for physicians to facilitate the choice of more appropriate bDMARDs to treat patients with autoimmune arthritis and for basic researchers to understand the current strategies of bDMARD usage and hopefully to develop more powerful bDMARDs with fewer safety concerns.