Discovery and characterization of olokizumab: a humanized antibody targeting interleukin-6 and neutralizing gp130-signaling

Structural basis of signaling complex inhibition by IL-6 domain-swapped dimers

Interleukin-6 (IL-6) is a multifaceted cytokine essential in many immune system processes and their regulation. It also plays a key role in hematopoiesis, and in triggering the acute phase reaction. IL-6 overproduction is critical in chronic inflammation associated with autoimmune diseases like rheumatoid arthritis and contributes to cytokine storms in COVID-19 patients. Over 20 years ago, researchers proposed that IL-6, which is typically monomeric, can also form dimers via a domain-swap mechanism, with indirect evidence supporting their existence. The physiological significance of IL-6 dimers was shown in B-cell chronic lymphocytic leukemia. However, no structures have been reported so far. Here, we present the crystal structure of an IL-6 domain-swapped dimer that computational approaches could not predict. The structure explains why the IL-6 dimer is antagonistic to the IL-6 monomer in signaling complex formation and provides insights for IL-6 targeted therapies.

Advancing therapeutic frontiers: a pipeline of novel drugs for luminal and perianal Crohn's disease management

Crohn's disease (CD) is a chronic, complex inflammatory disorder of the gastrointestinal tract that presents significant therapeutic challenges. Despite the availability of a wide range of treatments, many patients experience primary non-response, secondary loss of response, or adverse events, limiting the overall effectiveness of current therapies. Clinical trials often report response rates below 60%, partly due to stringent inclusion criteria. Emerging therapies that target novel pathways offer promise in overcoming these limitations. This review explores the latest investigational drugs in phases I, II, and III clinical trials for treating both luminal and perianal CD. We highlight promising therapies that target known mechanisms, including selective Janus kinase inhibitors, anti-adhesion molecules, tumor necrosis factor inhibitors, and IL-23 selective inhibitors. In addition, we delve into novel therapeutic strategies such as sphingosine-1-phosphate receptor modulators, miR-124 upregulators, anti-fractalkine (CX3CL1), anti-TL1A, peroxisome proliferator-activated receptor gamma agonists, TGFBRI/ALK5 inhibitors, anti-CCR9 agents, and other innovative small molecules, as well as combination therapies. These emerging approaches, by addressing new pathways and mechanisms of action, have the potential to surpass the limitations of existing treatments and significantly improve CD management. However, the path to developing new therapies for inflammatory bowel disease (IBD) is fraught with challenges, including complex trial designs, ethical concerns regarding placebo use, recruitment difficulties, and escalating costs. The landscape of IBD clinical trials is shifting toward greater inclusivity, improved patient diversity, and innovative trial designs, such as adaptive and Bayesian approaches, to address these challenges. By overcoming these obstacles, the drug development pipeline can advance more effective, accessible, and timely treatments for CD.

Targeting inerleukin-6 for renoprotection

Sterile inflammation has been increasingly recognized as a hallmark of non-infectious kidney diseases. Induction of pro-inflammatory cytokines in injured kidney tissue promotes infiltration of immune cells serving to clear cell debris and facilitate tissue repair. However, excessive or prolonged inflammatory response has been associated with immune-mediated tissue damage, nephron loss, and development of renal fibrosis. Interleukin 6 (IL-6) is a cytokine with pleiotropic effects including a major role in inflammation. IL-6 signals either via membrane-bound (classic signaling) or soluble receptor forms (trans-signaling) thus affecting distinct cell types and eliciting various metabolic, cytoprotective, or pro-inflammatory reactions. Antibodies neutralizing IL-6 or its receptor have been developed for therapy of autoimmune and chronic non-renal inflammatory diseases. Small molecule inhibitors of Janus kinases acting downstream of the IL-6 receptor, as well as recombinant soluble glycoprotein 130 variants suppressing the IL-6 trans-signaling add to the available therapeutic options. Animal data and accumulating clinical experience strongly suggest that suppression of IL-6 signaling pathways bears therapeutic potential in acute and chronic kidney diseases. The present work analyses the renoprotective potential of clinically relevant IL-6 signaling inhibitors in acute kidney injury, chronic kidney disease, and kidney transplantation with focus on current achievements and future prospects.

Inflammation-mediated drug interactions of olokizumab and cytochrome P450 activities in patients with rheumatoid arthritis

AIMS

In patients with rheumatoid arthritis (RA), interleukin (IL)-6 affects the activity of cytochrome P450 (CYP) enzymes. Treatment with anti-IL-6 therapy can reverse the IL-6-mediated downregulation of CYP enzymes, resulting in changes in plasma levels of CYP substrates. The primary objective of this study was to evaluate the impact of the IL-6 inhibitor olokizumab on the pharmacokinetics of CYP probe substrates in subjects with active RA.

METHODS

Seventeen patients with active RA were orally administered a phenotyping cocktail of midazolam (CYP3A4 substrate), omeprazole (CYP2C19 substrate), warfarin (CYP2C9 substrate) and caffeine (CYP1A2 substrate) alone and 2 weeks after a single subcutaneous injection of 128 mg olokizumab. The pharmacokinetic parameters of each substrate were calculated using noncompartmental analysis.

RESULTS

Sixteen of 17 enrolled patients received the complete doses of the cocktail drugs and olokizumab and were eligible for the pharmacokinetic evaluations. After single-dose administration of olokizumab, the exposure of midazolam and omeprazole decreased by 30-33% and 26-32%, respectively, compared to when the substrates were administered along via cocktail. In the presence of olokizumab, caffeine exposure increased by 19-23% compared to caffeine administration alone. There were no significant changes in S-warfarin exposure.

CONCLUSION

In patients with active RA, olokizumab potentially reverses the IL-6-mediated suppression of CYP3A4 and CYP2C19. According to FDA guidance, olokizumab is considered a weak inducer of CYP3A4 and CYP2C19.

Monoclonal antibodies: From magic bullet to precision weapon

Monoclonal antibodies (mAbs) are used to prevent, detect, and treat a broad spectrum of non-communicable and communicable diseases. Over the past few years, the market for mAbs has grown exponentially with an expected compound annual growth rate (CAGR) of 11.07% from 2024 (237.64 billion USD estimated at the end of 2023) to 2033 (679.03 billion USD expected by the end of 2033). Ever since the advent of hybridoma technology introduced in 1975, antibody-based therapeutics were realized using murine antibodies which further progressed into humanized and fully human antibodies, reducing the risk of immunogenicity. Some benefits of using mAbs over conventional drugs include a drastic reduction in the chances of adverse reactions, interactions between drugs, and targeting specific proteins. While antibodies are very efficient, their higher production costs impede the process of commercialization. However, their cost factor has been improved by developing biosimilar antibodies as affordable versions of therapeutic antibodies. Along with the recent advancements and innovations in antibody engineering have helped and will furtherly help to design bio-better antibodies with improved efficacy than the conventional ones. These novel mAb-based therapeutics are set to revolutionize existing drug therapies targeting a wide spectrum of diseases, thereby meeting several unmet medical needs. This review provides comprehensive insights into the current fundamental landscape of mAbs development and applications and the key factors influencing the future projections, advancement, and incorporation of such promising immunotherapeutic candidates as a confrontation approach against a wide list of diseases, with a rationalistic mentioning of any limitations facing this field.

CytoSIP: an annotated structural atlas for interactions involving cytokines or cytokine receptors

Therapeutic agents targeting cytokine-cytokine receptor (CK-CKR) interactions lead to the disruption in cellular signaling and are effective in treating many diseases including tumors. However, a lack of universal and quick access to annotated structural surface regions on CK/CKR has limited the progress of a structure-driven approach in developing targeted macromolecular drugs and precision medicine therapeutics. Herein we develop CytoSIP (Single nucleotide polymorphisms (SNPs), Interface, and Phenotype), a rich internet application based on a database of atomic interactions around hotspots in experimentally determined CK/CKR structural complexes. CytoSIP contains: (1) SNPs on CK/CKR; (2) interactions involving CK/CKR domains, including CK/CKR interfaces, oligomeric interfaces, epitopes, or other drug targeting surfaces; and (3) diseases and phenotypes associated with CK/CKR or SNPs. The database framework introduces a unique tri-level SIP data model to bridge genetic variants (atomic level) to disease phenotypes (organism level) using protein structure (complexes) as an underlying framework (molecule level). Customized screening tools are implemented to retrieve relevant CK/CKR subset, which reduces the time and resources needed to interrogate large datasets involving CK/CKR surface hotspots and associated pathologies. CytoSIP portal is publicly accessible at https://CytoSIP.biocloud.top , facilitating the panoramic investigation of the context-dependent crosstalk between CK/CKR and the development of targeted therapeutic agents.

Novel and potential future therapeutic options in systemic autoimmune diseases

Autoimmune inflammation is caused by the loss of tolerance to specific self-antigens and can result in organ-specific or systemic disorders. Systemic autoimmune diseases affect a significant portion of the population with an increasing rate of incidence, which means that is essential to have effective therapies to control these chronic disorders. Unfortunately, several patients with systemic autoimmune diseases do not respond at all or just partially respond to available conventional synthetic disease-modifying antirheumatic drugs and targeted therapies. However, during the past few years, some new medications have been approved and can be used in real-life clinical settings. Meanwhile, several new candidates appeared and can offer promising novel treatment options in the future. Here, we summarize the newly available medications and the most encouraging drug candidates in the treatment of systemic lupus erythematosus, rheumatoid arthritis, Sjögren's disease, systemic sclerosis, systemic vasculitis, and autoimmune myositis.

Comparison of the efficacy and safety of olokizumab at different dosages in patients with active rheumatoid arthritis: a network meta-analysis of randomized controlled trials

OBJECTIVE

This study aimed to assess the relative efficacy and safety of olokizumab at different dosages in patients with active rheumatoid arthritis (RA).

METHODS

We performed a Bayesian network meta-analysis to combine direct and indirect evidence from randomized controlled trials (RCTs) to examine the efficacy and safety of olokizumab administered intravenously to RA patients at 64 mg/kg every 2 or 4 weeks (Q2 or Q4W).

RESULTS

Five RCTs comprising 2609 patients met the inclusion criteria. Both olokizumab Q2 and Q4W treatments achieved a significant American College of Rheumatology 20% response (ACR20) compared with the placebo (odds ratio [OR] 3.21, 95% credible interval [CrI] 2.53-4.09; OR 3.05, 95% CrI 2.43-3.86). However, olokizumab Q2W was associated with the most favorable surface using the cumulative ranking curve (SUCRA) for the ACR20 response rate. The ranking probability based on the SUCRA indicated that olokizumab Q2W had the highest probability of being considered the best treatment option for achieving the ACR20 response rate, followed by olokizumab Q4W, adalimumab, and placebo. The ACR50 and 70 response rates showed a similar distribution pattern to the ACR20 response rate, except that olokizumab Q4W had a higher-ranking probability than olokizumab Q2W for ACR50. The SUCRA rating likelihood of adverse events (AEs) and withdrawal due to AEs showed that a placebo was likely to be the best intervention.

CONCLUSION

Both olokizumab Q2 and Q4W were efficacious and well-tolerated treatments for active RA.

The role of inflammation in autoimmune disease: a therapeutic target

Autoimmune diseases (AIDs) are immune disorders whose incidence and prevalence are increasing year by year. AIDs are produced by the immune system's misidentification of self-antigens, seemingly caused by excessive immune function, but in fact they are the result of reduced accuracy due to the decline in immune system function, which cannot clearly identify foreign invaders and self-antigens, thus issuing false attacks, and eventually leading to disease. The occurrence of AIDs is often accompanied by the emergence of inflammation, and inflammatory mediators (inflammatory factors, inflammasomes) play an important role in the pathogenesis of AIDs, which mediate the immune process by affecting innate cells (such as macrophages) and adaptive cells (such as T and B cells), and ultimately promote the occurrence of autoimmune responses, so targeting inflammatory mediators/pathways is one of emerging the treatment strategies of AIDs. This review will briefly describe the role of inflammation in the pathogenesis of different AIDs, and give a rough introduction to inhibitors targeting inflammatory factors, hoping to have reference significance for subsequent treatment options for AIDs.

Dynamics of clinical manifestations and cytokine concentrations in patients with rheumatoid arthritis on olokizumab therapy

The aim of the study was to investigate the dynamics of clinical and laboratory parameters of inflammatory disease activity and cytokines in patients with rheumatoid arthritis (RA) against the background of olokizumab (OKZ) treatment.Materials and methods. Ten patients with a reliable diagnosis of RA were examined: patients’ age was 46.00 (30.00; 60.00) years, duration of disease was 9.0 (3.0; 12,0) years. All patients had moderate to high disease activity: DAS28-ESR (Disease Activity Score 28 with Erythrocyte Sedimentation Rate) – 513 (4.34; 5,80); CDAI (Clinical Disease Activity Index) – 30.00 (24.00; 35.00); SDAI (Simplified Disease Activity Index) – 31.86 (24.36; 38.59). All patients were treated with OKZ at a dose of 64 mg subcutaneously every 4 weeks on the background of therapy with methotrexate, leflunomide, nonsteroidal anti-inflammatory drugs, and glucocorticoids. Observations were performed before treatment and after 3, 6 months of therapy. Serum levels of 15 cytokines: interleukin (IL) 1β, IL-4, IL-6, tumor necrosis factor α (TNF-α), interferon (INF) γ, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, sCD40L, – were examined using multiplex xMAR technology.Results. After 3 and 6 months of OKZ therapy, there was a significant decrease in DAS28-ESR of 3.53 (2.83; 4.26) and 3.48 (2.8; 4.10); CDAI – 11.00 (6.0; 16.00) and 10.0 (5.0; 15.0); SDAI – 10.0 (5.0; 15.0) and 10.17 (7.02; 15.02); C-reactive protein (CRP) concentrations (initial – 14.30 (7.00; 24.70) mg/l, after 3 months – 0.70 (0.40; 0.90) mg/l and after 6 months – 0.65 (0.20; 3.00) mg/l). After 3 months of treatment we found an increase in IL-6 concentration (initial – 1.89 (1.61; 2.33) pg/ml and 89.98 (35.09; 165.84) pg/ml; p<0.01), after 6 months – its level decreased to 44.88 (5.25; 80.90) pg/ml without reaching, however, the initial values (p<0.05). Against the background of OCZ, after 3 months of treatment there was an increase in IL-25 concentration (p<0.01), and after 6 months of therapy – TNF-α (p<0.05).Conclusion. The use of OKZ leads to an increase in the concentration of total IL-6 in the blood serum of RA patients, while the clinical and laboratory activity of the disease decreases.

New Targets and Strategies for Rheumatoid Arthritis: From Signal Transduction to Epigenetic Aspect

Rheumatoid arthritis (RA) is a chronic autoimmune disease that can lead to joint damage and even permanent disability, seriously affecting patients' quality of life. At present, the complete cure for RA is not achievable, only to relieve the symptoms to reduce the pain of patients. Factors such as environment, genes, and sex can induce RA. Presently, non-steroidal anti-inflammatory drugs, DRMADs, and glucocorticoids are commonly used in treating RA. In recent years, some biological agents have also been applied in clinical practice, but most have side effects. Therefore, finding new mechanisms and targets for treating RA is necessary. This review summarizes some potential targets discovered from the perspective of epigenetics and RA mechanisms.

Characterization of HZ0412a, a novel potent humanized anti-IL-6 receptor antibody that blocks IL-6R binding to gp130

Dysregulated elevation of interleukin-6 (IL-6) signaling is implicated in the pathogenesis of multiple pathophysiological states, and the functional neutralization of the IL-6 pathway with monoclonal antibodies has been proven an effective therapeutic method in treating various diseases with abnormally enhanced IL-6 signaling, and its clinical indications are expanding. Here, we report that by using the conventional hybridoma technology and humanization mutation method, we develop a novel humanized anti-IL-6 receptor (IL-6R) antibody-namely, HZ0412a. In our study, we found that HZ0412a exhibits higher binding affinity to soluble recombinant human IL-6R than tocilizumab. Importantly, in contrast to tocilizumab-a humanized anti-IL-6R antibody approved by the US Food and Drug Administration for the treatment of rheumatoid arthritis, juvenile idiopathic arthritis, giant cell arteritis and Castleman's disease-HZ0412a does not significantly affect the binding of IL-6 to IL-6R. Further analysis revealed that HZ0412a prevents IL-6R from binding to gp130 in vitro, while tocilizumab has a minimal effect under the same condition. Using various cell-based assays, we demonstrate that HZ0412a is noninferior to tocilizumab in inhibiting IL-6 signaling. Finally, we showed that HZ0412a is well tolerated in cynomolgus monkeys after a single subcutaneous injection at a dose of 1 or 5 mg/kg. Taken together, our results indicated that HZ0412a targets an epitope on human IL-6R that is different from that of tocilizumab, and the epitope region is essential for the interaction between IL-6R and gp130. This distinctive mode of action plus its high affinity to IL-6R led to the high potency of HZ0412a in suppressing in vitro IL-6 signaling.

Targeting Olokizumab-Interleukin 6 interaction interface to discover novel IL-6 inhibitors

The IL-6/IL-6R or IL-6/GP130 protein-protein interactions play a significant role in controlling the development of chronic inflammatory diseases, such as rheumatoid arthritis, Castleman disease, psoriasis, and, most recently, COVID-19. Modulating or antagonizing protein-protein interactions of IL6 binding to its receptors by oral drugs promises similar efficacy to biological therapy in patients, namely monoclonal antibodies. In this study, we used a crystal structure of the Fab part of olokizumab in a complex with IL-6 (PDB ID: 4CNI) to uncover starting points for small molecule IL-6 antagonist discovery. Firstly, a structure‑based pharmacophore model of the protein active site cavity was generated to identify possible candidates, followed by virtual screening with a significant database Drugbank. After the docking protocol validation, a virtual screening by molecular docking was carried out and a total of 11 top hits were reported. Detailed analysis of the best scoring molecules was performed with ADME/T analysis and molecular dynamics simulation. Furthermore, the Molecular Mechanics-Generalized Born Surface Area (MM/GBSA) technique has been utilized to evaluate the free binding energy. Based on the finding, one newly obtained compound in this study, namely DB15187, may serve as a lead compound for the discovery of IL-6 inhibitors.Communicated by Ramaswamy H. Sarma.

The efficacy and safety of olokizumab for rheumatoid arthritis: a systematic review, pairwise, and network meta-analysis

Olokizumab (OKZ) is a novel IL-6 inhibitor that directly targets IL-6 rather than its receptor. We aim to evaluate the efficacy and safety of OKZ for patients with rheumatoid arthritis (RA) and to investigate the optimal treatment regimen. A systematic review, pairwise, and network meta-analysis synthesizing randomized controlled trials (RCTs) from WOS, CENTRAL, SCOPUS, EMBASE, and PubMed until August 31, 2022. We used the risk ratio (RR) and mean difference (MD) for dichotomous and continuous outcomes, respectively, presented with the corresponding 95% confidence interval (CI). We registered our protocol in PROSPERO with ID: CRD42022358082. Five RCTs with 2277 patients were included. OKZ significantly improved the American College of Rheumatology criteria (ACR) 20 (RR: 1.97 with 95% CI [1.49, 2.58], P = 0.00001), ACR50 (RR: 3.83 with 95% CI [2.13, 6.87], P = 0.00001), ACR70 (RR: 3.83 with 95% CI [2.13, 6.87], P = 0.00001), disease activity score 28 based on C-reactive protein (DAS28-CRP) (RR: 3.91 with 95% CI [2.65, 5.79], P = 0.00001), clinical disease activity index (CDAI) (RR: 2.80 with 95% CI [1.43, 5.48], P = 0.003), and health assessment questionnaire disability index (HAQ-DI) (MD: - 0.28 with 95% CI [- 0.38, - 0.18], P = 0.00001) after 12 weeks, compared to placebo. However, OKZ was also associated with a higher incidence of any adverse events (AEs) (RR: 1.15 with 95% CI [1.06, 1.25], P = 0.0005) and AEs leading to drug discontinuation (RR: 1.86 with 95% CI [1.05, 3.29], P = 0.03). OKZ is effective and with acceptable safety profile when administrated with methotrexate in patients with RA not adequately controlled by tumor necrosis factor inhibitors; however, more large-scale RCTs are still required to investigate the optimal dosing, long-term effects, and comparative efficacy versus established biological DMARDs. Key Points • OKZ is effective especially with methotrexate in RA patients.

THE ROLE OF NEUTROPHIL EXTRACELLULAR TRAPS (NETS) IN THE IMMUNOPATHOGENESIS OF SEVERE COVID-19: POTENTIAL IMMUNOTHERAPEUTIC STRATEGIES REGULATING NET FORMATION AND ACTIVITY

The role of neutrophil granulocytes (NG) in the pathogenesis of COVID-19 is associated with the recruitment of NG into inflammatory foci, activation of their functions and enhanced formation of neutrophil extracellular networks (NETs). In this review, we analyzed a fairly large volume of scientific literature devoted to the peculiarities of the formation of NETs, their role in the pathogenesis of COVID-19, participation in the occurrence of immunothrombosis, vasculitis, acute respiratory distress syndrome, cytokine storm syndrome, multi-organ lesions. Convincing data are presented that clearly indicate the significant involvement of NETs in the immunopathogenesis of COVID-19 and the associated severe complications resulting from the intensification of the inflammation process, which is key for the course of infection caused by the SARS-CoV-2 virus. The presented role of NG and NETs, along with the role of other immune system cells and pro-inflammatory cytokines, is extremely important in understanding the development of an overactive immune response in severe COVID-19. The obtained scientific results, available today, allow identifying the possibilities of regulatory effects on hyperactivated NG, on the formation of NETs at various stages and on limiting the negative impact of already formed NETs on various tissues and organs. All of the above should help in the creation of new, specialized immunotherapy strategies designed to increase the chances of survival, reduce the severity of clinical manifestations in patients with COVID-19, as well as significantly reduce mortality rates. Currently, it is possible to use existing drugs and a number of new drugs are being developed, the action of which can regulate the amount of NG, positively affect the functions of NG and limit the intensity of NETs formation. Continuing research on the role of hyperactive NG and netosis, as well as understanding the mechanisms of regulation of the phenomenon of formation and restriction of NETs activity in severe COVID-19, apparently, are a priority, since in the future the new data obtained could become the basis for the development of targeted approaches not only to immunotherapy aimed at limiting education and blocking negative effects already formed NETs in severe COVID-19, but also to immunotherapy, which could be used in the complex treatment of other netopathies, first of all, autoimmune diseases, auto-inflammatory syndromes, severe purulent-inflammatory processes, including bacterial sepsis and hematogenous osteomyelitis.

Olokizumab's Effectiveness and Safety in Patients with Rheumatoid Arthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

In the development of rheumatoid arthritis, the cytokine interleukin-6 plays a role. An interleukin-6 cytokine-specific monoclonal antibody called olokizumab directly targets this cytokine. OKZ effectiveness and safety are being evaluated through this meta-analysis.

METHOD

I looked up every published randomized controlled study on Clinicaltrials.gov, Scopus, Web of Science, Cochrane, and PubMed. I conducted the study using both the Mantel-Haenszel and inverse variance approaches. I evaluated bias in the included studies using the risk of bias tool 2.

RESULTS

In this meta-analysis, five trials totalling 2227 participants, were examined. In contrast to the placebo group, the olokizumab group had a significantly higher incidence of American College of Rheumatology 20; RR = 1.83, 95% CI [1.69, 1.99], P < 0.00001. Regarding Health Assessment Questionnaire-Disability Index improvement, olokizumab significantly outperformed the placebo group; MD = -0.28, 95% CI [-0.32, -0.24], P < 0.00001. The incidence of treatment-emergent adverse events was significantly higher in the olokizumab group than in the placebo group; RR = 1.10, 95% CI [1.04, 1.17], P = 0.0006. Furthermore, the incidence of treatment-emergent serious adverse events did not differ significantly between the olokizumab group and the placebo group; RR = 0.85, 95% CI [0.60, 1.20], P = 0.35.

CONCLUSION

In patients with rheumatoid arthritis, olokizumab combined methotrexate is well tolerated and more effective than placebo plus methotrexate.

CHARACTERISTICS OF OLOKIZUMAB PHARMACOKINETICS IN PATIENTS WITH NOVEL CORONAVIRUS INFECTION COVID-19

The aim of the article is to study pharmacokinetic characteristics of intravenous olokizumab in patients with moderate COVID-19 to relieve a hyperinflammation syndrome.

Materials and methods. The pharmacokinetic study was conducted as a part of a phase III clinical study (RESET, NCT05187793) on the efficacy and safety of a new olokizumab regimen (intravenous, at the doses of 128 mg or 256 mg) in COVID-19 patients. Plasma concentrations of olokizumab were determined by the enzyme immunoassay. The population analysis was performed using a previously developed pharmacokinetic model based on a linear two compartment.

Results. The pharmacokinetic analysis included the data from 8 moderate COVID-19 patients who had been administrated with olokizumab intravenously at the dose of 128 mg. According to the analysis results in this population, there was an increase in the drug clearance, compared with the data obtained in healthy volunteers and the patients with rheumatoid arthritis: 0.435, 0.178 and 0.147 l/day, respectively. The parameters analysis within the framework of a population pharmacokinetic model showed that the main factors for the increased olokizumab clearance are a high body mass index. In addition, the presence of COVID-19 itself is an independent factor in increasing the drug clearance.

Conclusion. After the intravenous olokizumab administration, an increase in the drug clearance is observed in moderate COVID-19 patients against the background of the disease course. The main contribution to the increased clearance is made by the characteristics of the population of COVID-19 patients associated with the risk of a severe disease and inflammation. When administered intravenously at the dose of 128 mg, a therapeutically significant olokizumab level was maintained throughout the acute disease phase for 28 days.

REVMATOİD ARTRİTİN MÜALİCƏSİNDƏ İL-6 ƏLEYHİNƏ MONOKLONAL ANTİCİSİMLƏRİN TƏTBİQİNİN PERSPEKTİVLƏRİ

В настоящем обзоре рассматриваются данные по безопасности и эффективности применения олокизумаба (ОКЗ) при ревматоидном артрите на основе анализа данных трех исследований третьей фазы. Была проведена оценка двух режимов применения ОКЗ 64 мг (каждые 2 недели/к2н и каждые 4 недели/к4н) в сравнении с плацебо и адалимумабом (CREDO2) в дополнении к метотрексату (МТ) в популяции пациентов с недостаточным ответом на МТ (CREDO1 и CREDO2) и ингибиторы ФНО (CREDO3). Была доказана эффективность олокизумаба, при этом, сравнительная эффективность ОКЗ с АДА у пациентов была сопоставимой и составляла: 70,3% пациентов, получавших ОКЗ (к2н), 71,4% - ОКЗ (к4н), 66,9% адалимумаб в отличие от 44,4%  на плацебо (p<0,0001) по первичной конечной точке ACR20. Частота ответа ACR20 не зависела от пола, возраста, индекса массы тела, исходной тяжести РА, длительности предшествующей терапии МТ, обнаружением антител к циклическим цитруллинированным белкам и ревматоидного фактора. Отмечена положительная динамика со стороны многочисленных показателей эффективности, включая оценку качества жизни. Аналогичные результаты были получены в исследовании CREDO 3. При этом не было получено данных, которые могли отрицательно повлиять на оценку соотношения «польза-риски» для ОКЗ.

Təqdim edilmiş məqalədə revmatoid artritin 3-cü fazasında olokizumabın (OKZ) effektivliyini 2 tətbiq rejimində öyrənmək üçün aparılmış 3 tədqiqat işinin müqayisəli təhlili şərh edilmişdir. 2 tətbiq rejimində qiymətləndirmə aparılmışdır: OKZ-nin 64 mq-lıq dozada hər 2 həftədənbir və hər dörd həftədənbir tətbiqi plasebo və adalimumabla (CREDO 2) metotreksat (MT) əlavə edilməklə tədqiq edilmişdir. Tədqiqat metotreksata (CREDO 1 və CREDO 2) və şiş nekrozu faktorunun inhibitoruna (CREDO 3) qeyri-kafi reaksiyası olan insan populyasiyası ilə müqayisədə aparılmışdır. Tədqiqat OKZ-nin adalimumab (ADA) ilə müqayisədə daha effektiv olduğunu göstərmişdir: ikihəftədənbir OKZ alan xəstələrdən 70,3 %-də, dördhəftədənbir alanlardan isə 71,4 %-də müsbət effekt alındığı halda ADA-nın tətbiqi zamanı nisbi yaxşılaşma xəstələrdən 66,9 %-də plasebonun tətbiqi zamanı isə 44,4 %-də qeydə alınmışdır. ACR 20 (American College of Rheumatology – 20) meyarları üzrə cavab tezliyi cinsiyyətdən, yaşdan, bədən kütləsi indeksindən, RA-nın agırlıq dərəcəsindən, metotreksatla müalicənin müddətindən, tsiklik sitrullinləşmiş zülalların və revmatoid faktorunun qandakı qatılığından asılı olmamışdır. OKZ ilə müalicə alan xəstələrdə müxtəlif effektivlik göstəricilərinin, o cümlədən həyat keyfiyyətinin müsbət dinamikası qeydə alınmışdır. CREDO 3 tədqiqatında da analoji nəticələr əldə edilmişdir. Eyni zamanda OKZ ilə müalicənin “Faydalılıq-risk” nisbətinin qiymətləndirilməsinə mənfi təsir göstərə biləcək heç bir əlamət müşahidə edilməmişdir.

This article provides a review of olokizumab (OKZ) efficacy in 2 modes in phase III rheumatoid arthritis. Treatment with OKZ 64 mg every 2 weeks and 4 weeks was compared to placebo and adalimumab (CREDO 2) in combination with methotrexate (MTX) in populations of patients with inadequate response to MTX (CREDO 1 and CREDO 2) and to TNF inhibitors (CREDO 3). Olokizumab efficacy was confirmed in all studies. The primary endpoint of the ACR20 (American College of Rheumatology - 20) response was achieved in the comparable number of patients in OKZ and adalimumab (ADA) treatment. It was registered in 70.3% of patients receiving OKZ 2 weeks group, 71.4% of patients receiving OKZ 4 weeks group, 66.9% of patients in the ADA group and 44.4% of patients in the placebo group (p<0.0001) (CREDO2). The percentage of ACR20 response in treatment arms did not depend on gender, age, body mass index, initial RA severity, previous duration of MTX treatment, presence of antibodies to cyclic citrullinated proteins and rheumatoid factor (CREDO1, CREDO2). Positive dynamics of various efficiency indicators, including quality of life, were recorded in patients treated with OKZ. Similar results were obtained in the CREDO 3 study. At the same time, there were no signs that could have a negative impact on the evaluation of the "Benefit-risk" ratio of treatment with OKZ.

Impact of interleukin-6 on T cells in kidney transplant recipients

Interleukin-6 (IL-6), a multifunctional proinflammatory cytokine, plays a key role in T cell activation, survival, and differentiation. Acting as a switch that induces the differentiation of naïve T cells into Th17 cells and inhibits their development into regulatory T cells, IL-6 promotes rejection and abrogates tolerance. Therapies that target IL-6 signaling include antibodies to IL-6 and the IL-6 receptor and inhibitors of janus kinases; several of these therapeutics have demonstrated robust clinical efficacy in autoimmune and inflammatory diseases. Clinical trials of IL-6 inhibition in kidney transplantation have focused primarily on its effects on B cells, plasma cells, and HLA antibodies. In this review, we summarize the impact of IL-6 on T cells in experimental models of transplant and describe the effects of IL-6 inhibition on the T cell compartment in kidney transplant recipients.

The prospects of interleukin-6 inhibition in rheumatoid arthritis: Olokizumab (novel monoclonal antibodies to IL-6)

Rheumatoid arthritis (RA) is a chronic immune-mediated rheumatic diseases (IMRDs) manifested with progressive destruction of joints, systemic inflammation of visceral organs and a wide range of co-morbidities associated with chronic inflammation. Among the cytokines involved in the pathogenesis of RA and certain other IMRDs, the role of interleukin (IL) 6 is of special interest. The introduction of mAbs tocilizumab (TCZ) and later sarilumab (SAR), both blocking the receptor of this cytokine, into clinical practice was an important achievement in the treatment of IIRDs at the beginning of the 21st century. As a novel approach in the treatment of RA, the humanized mAb against IL-6 olokizumab (OKZ) is in development by the Russian company R-PHARM under the license agreement with UCB Pharma. The review examines new data on efficacy and safety of OKZ in RA and the prospects of its use in rheumatology

Olokizumab, a monoclonal antibody against interleukin-6, in combination with methotrexate in patients with rheumatoid arthritis inadequately controlled by tumour necrosis factor inhibitor therapy: efficacy and safety results of a randomised controlled phase III study

Objectives

To assess the efficacy and safety of olokizumab (OKZ), a monoclonal antibody against the interleukin-6 (IL-6) cytokine, versus placebo (PBO) in patients with prior inadequate response to tumour necrosis factor inhibitors (TNFi-IRs).

Methods

In this 24-week multicentre, placebo-controlled, double-blind study, the patients were randomised in a 2:2:1 ratio to receive subcutaneously administered OKZ 64 mg once every 2 weeks (q2w), OKZ 64 mg once every 4 weeks (q4w) or PBO plus methotrexate. At week 16, the patients on PBO were randomised to receive either OKZ regime. The primary endpoint was the proportion of patients achieving an American College of Rheumatology 20% (ACR20) response at week 12. Disease Activity Score 28-joint count C-reactive protein (DAS28 (CRP))<3.2 at week 12 was the major secondary efficacy endpoint. Safety and immunogenicity were assessed.

Results

In 368 patients randomised, ACR20 response rates were 60.9% in OKZ q2w, 59.6% in OKZ q4w and 40.6% in PBO (p<0.01 for both comparisons). Achievement of DAS28 (CRP) <3.2 was significantly different, favouring the OKZ arms. Improvements in efficacy and patient-reported outcomes were maintained throughout 24 weeks and were noted after week 16 in patients who switched from PBO.

Dose-related treatment-emergent serious adverse events were 7% in OKZ q2w, 3.2% in OKZ q4w and none in the PBO group.

Conclusions

Direct inhibition of IL-6 with OKZ resulted in significant improvements in the signs and symptoms of rheumatoid arthritis compared with PBO in TNF-IR patients with a similar safety profile as observed for monoclonal antibodies to the IL-6 receptor.

Trial registration number

NCT02760433.

Olokizumab versus Placebo or Adalimumab in Rheumatoid Arthritis

BACKGROUND

The cytokine interleukin-6 is involved in the pathogenesis of rheumatoid arthritis. Olokizumab, a humanized monoclonal antibody targeting the interleukin-6 cytokine directly, is being tested for the treatment of rheumatoid arthritis.

METHODS

In a 24-week, phase 3, multicenter, placebo- and active-controlled trial, we randomly assigned (in a 2:2:2:1 ratio) patients with rheumatoid arthritis and an inadequate response to methotrexate to receive subcutaneous olokizumab at a dose of 64 mg every 2 or 4 weeks, adalimumab (40 mg every 2 weeks), or placebo; all patients continued methotrexate therapy. The primary end point was an American College of Rheumatology 20 (ACR20) response (≥20% fewer tender and swollen joints and ≥20% improvement in three of five other domains) at week 12, with each olokizumab dose tested for superiority to placebo. We also tested the noninferiority of each olokizumab dose to adalimumab with respect to the percentage of patients with an ACR20 response (noninferiority margin, -12 percentage points in the lower boundary of the 97.5% confidence interval for the difference between groups).

RESULTS

A total of 464 patients were assigned to receive olokizumab every 2 weeks, 479 to receive olokizumab every 4 weeks, 462 to receive adalimumab, and 243 to receive placebo. An ACR20 response at week 12 occurred in 44.4% of the patients receiving placebo, in 70.3% receiving olokizumab every 2 weeks (difference vs. placebo, 25.9 percentage points; 97.5% confidence interval [CI], 17.1 to 34.1), in 71.4% receiving olokizumab every 4 weeks (difference vs. placebo, 27.0 percentage points; 97.5% CI, 18.3 to 35.2), and in 66.9% receiving adalimumab (difference vs. placebo, 22.5 percentage points; 95% CI, 14.8 to 29.8) (P<0.001 for the superiority of each olokizumab dose to placebo). Both olokizumab doses were noninferior to adalimumab with respect to the percentage of patients with an ACR20 response at week 12 (difference, 3.4 percentage points [97.5% CI, -3.5 to 10.2] with olokizumab every 2 weeks and 4.5 percentage points [97.5% CI, -2.2 to 11.2] with olokizumab every 4 weeks). Adverse events, most commonly infections, occurred in approximately 70% of the patients who received olokizumab. Antibodies against olokizumab were detected in 3.8% of the patients receiving the drug every 2 weeks and in 5.1% of those receiving it every 4 weeks.

CONCLUSIONS

In patients with rheumatoid arthritis who were receiving maintenance methotrexate, olokizumab was superior to placebo and noninferior to adalimumab in producing an ACR20 response at 12 weeks. Larger and longer trials are required to determine the efficacy and safety of olokizumab in patients with rheumatoid arthritis. (Supported by R-Pharm; CREDO2 ClinicalTrials.gov number, NCT02760407.).

Network Pharmacology and Molecular Docking Elucidate the Underlying Pharmacological Mechanisms of the Herb Houttuynia cordata in Treating Pneumonia Caused by SARS-CoV-2

Used in Asian countries, including China, Japan, and Thailand, Houttuynia cordata Thumb (H. cordata; Saururaceae, HC) is a traditional herbal medicine that possesses favorable antiviral properties. As a potent folk therapy used to treat pulmonary infections, further research is required to fully elucidate the mechanisms of its pharmacological activities and explore its therapeutic potential for treating pneumonia caused by SARS-CoV-2. This study explores the pharmacological mechanism of HC on pneumonia using a network pharmacological approach combined with reprocessing expression profiling by high-throughput sequencing to demonstrate the therapeutic mechanisms of HC for treating pneumonia at a systemic level. The integration of these analyses suggested that target factors are involved in four signaling pathways, including PI3K-Akt, Jak-STAT, MAPK, and NF-kB. Molecular docking and molecular dynamics simulation were applied to verify these results, indicating a stable combination between four metabolites (Afzelin, Apigenin, Kaempferol, Quercetin) and six targets (DPP4, ELANE, HSP90AA1, IL6, MAPK1, SERPINE1). These natural metabolites have also been reported to bind with ACE2 and 3CLpro of SARS-CoV-2, respectively. The data suggest that HC exerts collective therapeutic effects against pneumonia caused by SARS-CoV-2 and provides a theoretical basis for further study of the active drug-like ingredients and mechanism of HC in treating pneumonia.

Application and prospect of targeting innate immune sensors in the treatment of autoimmune diseases

Dysregulation of auto-reactive T cells and autoantibody-producing B cells and excessive inflammation are responsible for the occurrence and development of autoimmune diseases. The suppression of autoreactive T cell activation and autoantibody production, as well as inhibition of inflammatory cytokine production have been utilized to ameliorate autoimmune disease symptoms. However, the existing treatment strategies are not sufficient to cure autoimmune diseases since patients can quickly suffer a relapse following the end of treatments. Pattern recognition receptors (PRRs), including Toll-like receptors (TLRs), Nod-like receptors (NLRs), RIG-I like receptors (RLRs), C-type lectin receptors (CLRs) and various nucleic acid sensors, are expressed in both innate and adaptive immune cells and are involved in the development of autoimmune diseases. Here, we have summarized advances of PRRs signaling pathways, association between PRRs and autoimmune diseases, application of inhibitors targeting PRRs and the corresponding signaling molecules relevant to strategies targeting autoimmune diseases. This review emphasizes the roles of different PRRs in activating both innate and adaptive immunity, which can coordinate to trigger autoimmune responses. The review may also prompt the formulation of novel ideas for developing therapeutic strategies against autoimmune diseases by targeting PRRs-related signals.

In silico screening for oligopeptides useful as capture and reporting probes for interleukin-6 biosensing

IL-6 is an important interleukin associated with inflammation and several diseases such as cancer. Evaluation of its levels in human blood sera is a critical step for an accurate diagnosis of the diseases. Our goal is to design peptides that can selectively bind in different poses with good affinities to IL-6. For this purpose, we started from the crystal structures of different IL-6/protein complexes available in the Protein Data Bank (PDB) to select short peptides in the interaction zones, in which we intentionally introduced point mutations to increase their stability and affinity. To examine their usefulness as capture and reporting probes for the IL-6 biosensing, the five peptides and their interaction with IL-6 were studied in saline aqueous solution. Molecular docking, MD, and MM-PBSA were used to investigate the affinity and stability of these complexes. The conformational changes, the distance between the mass centers, the gyration radii, and the numbers of hydrogen bonds were analyzed to select the most suitable candidates. Three peptides, namely CTE17, CAY15 and CSE25, have the highest affinities presenting significant numbers of residues that have contact frequencies greater than 50% of simulation run time and are the most promising candidates. CTE17 and CSE25 showed they can form a stable sandwich with the target protein. For sake of comparison, we examined the previously known peptides (FND20, INL19 and CEK17) having affinity to IL-6 and the affinity of the lead i.e. CSE25 to two other interleukin family members (IL-4 and to IL-10).

Silybin phytosome attenuates cerebral ischemia-reperfusion injury in rats by suppressing oxidative stress and reducing inflammatory response: In vivo and in silico approaches

The present study was aimed to develop silybin phytosome (SIBP) and evaluate its effectiveness against cerebral ischemia-reperfusion (CIR) injury in rats. Initially, SIBP was prepared and characterized with Fourier transform-infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. Drug loading and entrapment efficiency of SIBP were also calculated. High-performance liquid chromatography was used to carry out bioavailability studies of SIBP. Adult Wistar rats were divided randomly into five groups. The CIR injury was induced after 14 days of pretreatment by occlusion of bilateral common carotid arteries for 30 min followed by 4 h of reperfusion. Biochemical estimation, histopathological studies, and in silico studies were carried out. Bioavailability studies revealed that SIB concentration was increased to twofolds in SIBP-treated rats. SIBP treatment significantly increases superoxide dismutase and glutathione levels while it decreases monoaldehyde, tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) levels in both the hippocampus and cortex of the SIBP-treated CIR-injured rats. Histopathological studies reveal SIBP treatment alleviates cortex cell death and arrangement of CA1 neurons in CIR-injured rats. In silico studies against proteins (TNF-α and IL-6) involved in cerebral ischemia revealed that silybin (SIB) exhibits strong binding interaction with the target proteins when compared to thalidomide which was used as the positive control. Phytosome increase SIB bioavailability and SIBP treatment showed promising results when compared to treatment with SIB only. Based on our study, we conclude that phytosome is a suitable drug delivery agent to the brain for SIB as SIBP treatment was able to provide neuroprotective action against CIR injury.

Genetic and Clinical Factors Associated with Olokizumab Treatment in Russian Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease and its treatment is an urgent problem of rheumatology. Olokizumab (OKZ) is a new humanized monoclonal antibody targeting IL-6 and is one of the few promising drugs for RA therapy. One-hundred-and-twenty-five DNA samples from Russian patients with RA, treated with olokizumab, were genotyped with an NGS panel containing 60 single nucleotide polymorphisms (SNPs) and the whole coding sequences of IL6, IL6R, TNFRSF1A, CTLA4, IL10, IL23R, and PADI4; and by RT-PCR for HLA-DRB1 and HLA-B. Associations of polymorphic variants with olokizumab efficacy according to the scores ACR20, ACR50, and DAS28-CRP were determined. We analyzed the obtained data by using logistic regression, ROC curves, and multivariate ANOVA. A high predictive value of the response to olokizumab therapy at 24 weeks was found for the combination of HLA-DRB1*04 and HLA-B*27 alleles with SNPs located in non-HLA genes (IL1B, IL17A, PADI4, DHODH, GLCCI1, IL23R, and TNFAIP3), and clinical characteristics (age, RA duration, and intensity) according to ACR20. Thus, the comprehensive assessment of polymorphic variants of HLA and non-HLA genes considering population characteristics in combination with clinical parameters allows for the elaboration of an RA prognostic panel.

Potential Pathophysiological Mechanisms Underlying Multiple Organ Dysfunction in Cytokine Release Syndrome

In recent decades, many serious respiratory infections have broken out all over the world, including SARS-CoV, MERS, and COVID-19. They are characterized by strong infectivity, rapid disease progression, high mortality, and poor prognosis. Excessive immune system activation results in cytokine hypersecretion, which is an important reason for the aggravation of symptoms, and can spread throughout the body leading to systemic multiple organ dysfunction, namely, cytokine release syndrome (CRS). Although many diseases related to CRS have been identified, the mechanism of CRS is rarely mentioned clearly. This review is intended to clarify the pathogenetic mechanism of CRS in the deterioration of related diseases, describe the important signaling pathways and clinical pathophysiological characteristics of CRS, and provide ideas for further research and development of specific drugs for corresponding targets to treat CRS.

Discovery and characterization of a monoclonal antibody targeting a conformational epitope of IL-6/IL-6Rα to inhibit IL-6/ IL-6Rα/gp130 hexameric signaling complex formation

The functional interleukin 6 (IL-6) signaling complex is a hexameric structure composed of IL-6, IL-6Rα, and the signaling receptor gp130. There are three different modes of IL-6 signaling, classic signaling, trans-signaling, and trans-presentation, which are not functionally redundant and mediate pleiotropic effects on both physiological and pathophysiological states. Monoclonal antibodies against IL-6 or IL-6Rα have been successfully developed for clinical application. However, designing therapeutic interventions that block specific modes of IL-6 signaling in a pathologically relevant manner remains a great challenge. Here, we constructed a fusion protein Hyper-IL-6 (HyIL-6) composed of human IL-6 and IL-6Rα to develop specific blocking antibodies against the IL-6/IL-6Rα complex. We successfully screened the monoclonal antibody C14mab, which can bind to HyIL-6 with the binding constant 2.86 × 10^-10 and significantly inhibit IL-6/IL-6Rα/gp130 complex formation. In vitro, C14mab effectively inhibited HyIL-6-stimulated signal transducer and activator of transcription 3 (STAT3) activation and related vascular endothelial growth factor (VEGF) induction. Moreover, C14mab efficaciously suppressed HyIL-6-induced acute phase response in vivo. Our data from hydrogen-deuterium exchange mass spectrometry demonstrate that C14mab mainly binds to site IIIa of IL-6 and blocks the final step in the interaction between gp130 and IL-6/IL-6Rα complex. Additionally, data from enzyme-linked immunosorbent assays and kinetics assays indicate that C14mab interacts simultaneously with IL-6 and IL-6Rα, while it does not interact with IL-6Rα alone. The unique features of C14mab may offer a novel alternative for IL-6 blockade and illuminate a better therapeutic intervention targeting IL-6.

The IL6-like Cytokine Family: Role and Biomarker Potential in Breast Cancer

IL6-like cytokines are a family of regulators with a complex, pleiotropic role in both the healthy organism, where they regulate immunity and homeostasis, and in different diseases, including cancer. Here we summarise how these cytokines exert their effect through the shared signal transducer IL6ST (gp130) and we review the extensive evidence on the role that different members of this family play in breast cancer. Additionally, we discuss how the different cytokines, their related receptors and downstream effectors, as well as specific polymorphisms in these molecules, can serve as predictive or prognostic biomarkers with the potential for clinical application in breast cancer. Lastly, we also discuss how our increasing understanding of this complex signalling axis presents promising opportunities for the development or repurposing of therapeutic strategies against cancer and, specifically, breast neoplasms.

IL-6 in the Ecosystem of Head and Neck Cancer: Possible Therapeutic Perspectives

Interleukin-6 (IL-6) is a highly potent cytokine involved in multiple biological processes. It was previously reported to play a distinct role in inflammation, autoimmune and psychiatric disorders, ageing and various types of cancer. Furthermore, it is understood that IL-6 and its signaling pathways are substantial players in orchestrating the cancer microenvironment. Thus, they appear to be potential targets in anti-tumor therapy. The aim of this article is to elucidate the role of IL-6 in the tumor ecosystem and to review the possible therapeutic approaches in head and neck cancer.

Unravelling the broader complexity of IL-6 involvement in health and disease

The classification of interleukin-6 (IL-6) as a pro-inflammatory cytokine undervalues the biological impact of this cytokine in health and disease. With broad activities affecting the immune system, tissue homeostasis and metabolic processes, IL-6 displays complex biology. The significance of these involvements has become increasingly important in clinical settings where IL-6 is identified as a prominent target for therapy. Here, clinical experience with IL-6 antagonists emphasises the need to understand the context-dependent properties of IL-6 within an inflammatory environment and the anticipated or unexpected consequences of IL-6 blockade. In this review, we will describe the immunobiology of IL-6 and explore the gamut of IL-6 bioactivity affecting the clinical response to biological drugs targeting this cytokine pathway.

Olokizumab, a monoclonal antibody against interleukin 6, in combination with methotrexate in patients with rheumatoid arthritis inadequately controlled by methotrexate: efficacy and safety results of a randomised controlled phase III study

Objective

To evaluate the efficacy and safety of olokizumab (OKZ) in patients with active rheumatoid arthritis despite treatment with methotrexate (MTX).

Methods

In this 24-week multicentre, placebo-controlled, double-blind study, patients were randomised 1:1:1 to receive subcutaneously administered OKZ 64 mg once every 2 weeks, OKZ 64 mg once every 4 weeks, or placebo plus MTX. The primary efficacy endpoint was the proportion of patients achieving an American College of Rheumatology 20% (ACR20) response at week 12. The secondary efficacy endpoints included percentage of subjects achieving Disease Activity Score 28-joint count based on C reactive protein <3.2, Health Assessment Questionnaire Disability Index at week 12, ACR50 response and Clinical Disease Activity Index ≤2.8 at week 24. Safety and immunogenicity were assessed throughout the study.

Results

A total of 428 patients were randomised. ACR20 responses were more frequent with OKZ every 2 weeks (63.6%) and OKZ every 4 weeks (70.4%) than placebo (25.9%) (p<0.0001 for both comparisons). There were significant differences in all secondary efficacy endpoints between OKZ-treated arms and placebo. Treatment-emergent serious adverse events (TESAEs) were reported by more patients in the OKZ groups compared with placebo. Infections were the most common TESAEs. No subjects developed neutralising antidrug antibodies.

Conclusions

Treatment with OKZ was associated with significant improvement in signs, symptoms and physical function of rheumatoid arthritis without discernible differences between the two regimens. Safety was as expected for this class of agents. Low immunogenicity was observed.

Trial registration number NCT02760368.

Long-term safety and efficacy of olokizumab in patients with rheumatoid arthritis and inadequate response to tumor necrosis factor inhibitor therapy in phase II studies

OBJECTIVE

This study aimed to evaluate the long-term safety and efficacy of olokizumab (OKZ), an anti-interleukin (IL)-6 monoclonal antibody, in patients with rheumatoid arthritis (RA) and inadequate response to tumor necrosis factor-alpha inhibitors.

METHODS

Eligible patients completed study RA0056, which tested several doses of OKZ, placebo (PBO), and tocilizumab (TCZ) plus methotrexate (MTX) in Western countries, and RA0083 included several doses of OKZ and PBO plus MTX in Asian countries. Both studies were followed by open-label extension (OLE) studies with OKZ 120 mg every 2 weeks, RA0057 and RA0089, respectively. Safety assessments were reported up to 124 weeks in RA0057 and 92 weeks in RA0089. Efficacy assessments were reported up to week 60 in RA0057 and week 52 in RA0089. No formal statistical hypothesis testing was performed, and missing data were not imputed.

RESULTS

A total of 190 patients in RA0057 and 103 patients in RA0089 received OKZ with median treatment duration of 14.1 and 10.1 months, respectively. Serious adverse events (SAEs) were reported in 44 patients (23.2%, 32.7 events per 100 patient-years [PY]) in RA0057 and in 13 patients (12.6%, 23.6 events per 100 PY) in RA0089. Among treatment-emergent adverse events (TEAEs), including SAEs, infections were the most common events. TEAEs leading to withdrawal were reported in 33 (17.4%) patients in RA0057 and in 7 (6.8%) patients in RA0089. Disease activity score 28-joint count on the basis of C-reactive protein level, clinical disease activity index, and simplified disease activity index, as well as the American College of Rheumatology 20%, 50%, and 70% response rates were maintained during the OLE studies, including in those who switched from PBO or TCZ. Improvements in patient-reported outcomes were maintained in OLEs as well.

CONCLUSION

In the 2 long-term studies, OKZ treatment demonstrated a safety profile expected for IL-6 blocking agents without new safety signals and led to sustained improvements in RA symptoms, physical function, and quality of life.

Analysis of miRNA Expression in Patients with Rheumatoid Arthritis during Olokizumab Treatment

Rheumatoid arthritis (RA) is the most common autoimmune disease worldwide. Epigenetic alternations of microRNAs (miRNAs) can contribute to its pathogenesis and progression. As the first line therapy with DMARDs is not always successful, other drugs and therapeutic targets should be applied. This study aims to measure the expression level of plasma miRNAs in RA patients treated with olokizumab and to evaluate their potential as prognostic biomarkers. The expression of 9 miRNAs was quantified in 103 RA patients before treatment and at weeks 12 and 24 of olokizumab therapy by reverse transcription-polymerase chain reaction (RT-PCR) assay and analyzed in groups of responders and non-responders. Almost all miRNAs changed their expression during therapy. The ROC curve analysis of the most prominent of them together with consequent univariate and multivariate regression analysis revealed statistically significant associations with the olokizumab therapy efficiency scores for miR-26b, miR-29, miR-451, and miR-522. Therefore, these miRNAs might be a potential therapeutic response biomarker.

Biosensing Cytokine IL-6: A Comparative Analysis of Natural and Synthetic Receptors

Cytokines are a family of proteins which play a major role in the regulation of the immune system and the development of several diseases, from rheumatoid arthritis to cancer and, more recently, COVID-19. Therefore, many efforts are currently being developed to improve therapy and diagnosis, as well as to produce inhibitory drugs and biosensors for a rapid, minimally invasive, and effective detection. In this regard, even more efficient cytokine receptors are under investigation. In this paper we analyze a set of IL-6 cytokine receptors, investigating their topological features by means of a theoretical approach. Our results suggest a topological indicator that may help in the identification of those receptors having the highest complementarity with the protein, a feature expected to ensure a stable binding. Furthermore, we propose and discuss the use of these receptors in an idealized experimental setup.

Structural Understanding of Interleukin 6 Family Cytokine Signaling and Targeted Therapies: Focus on Interleukin 11

Cytokines are small signaling proteins that have central roles in inflammation and cell survival. In the half-century since the discovery of the first cytokines, the interferons, over fifty cytokines have been identified. Amongst these is interleukin (IL)-6, the first and prototypical member of the IL-6 family of cytokines, nearly all of which utilize the common signaling receptor, gp130. In the last decade, there have been numerous advances in our understanding of the structural mechanisms of IL-6 family signaling, particularly for IL-6 itself. However, our understanding of the detailed structural mechanisms underlying signaling by most IL-6 family members remains limited. With the emergence of new roles for IL-6 family cytokines in disease and, in particular, roles of IL-11 in cardiovascular disease, lung disease, and cancer, there is an emerging need to develop therapeutics that can progress to clinical use. Here we outline our current knowledge of the structural mechanism of signaling by the IL-6 family of cytokines. We discuss how this knowledge allows us to understand the mechanism of action of currently available inhibitors targeting IL-6 family cytokine signaling, and most importantly how it allows for improved opportunities to pharmacologically disrupt cytokine signaling. We focus specifically on the need to develop and understand inhibitors that disrupt IL-11 signaling.

Protein-protein interactions: a structural view of inhibition strategies and the IL-23/IL-17 axis

Protein-protein interactions are central to biology and provide opportunities to modulate disease with small-molecule or protein therapeutics. Recent developments in the understanding of the tractability of protein-protein interactions are discussed with a focus on the ligandable nature of protein-protein interaction surfaces. General principles of inhibiting protein-protein interactions are illustrated with structural biology examples from six members of the IL-23/IL-17 signaling family (IL-1, IL-6, IL-17, IL-23 RORγT and TNFα). These examples illustrate the different approaches to discover protein-protein interaction inhibitors on a target-specific basis that has proven fruitful in terms of discovering both small molecule and biologic based protein-protein interaction inhibitors.

Targeting senescent cells: approaches, opportunities, challenges

Cellular senescence is a hallmark of aging, whose onset is linked to a series of both cell and non-cell autonomous processes, leading to several consequences for the organism. To date, several senescence routes have been identified, which play a fundamental role in development, tumor suppression and aging, among other processes. The positive and/or negative effects of senescent cells are directly related to the time that they remain in the organism. Short-term (acute) senescent cells are associated with positive effects; once they have executed their actions, immune cells are recruited to remove them. In contrast, long-term (chronic) senescent cells are associated with disease; they secrete pro-inflammatory and pro-tumorigenic factors in a state known as senescence-associated secretory phenotype (SASP). In recent years, cellular senescence has become the center of attention for the treatment of aging-related diseases. Current therapies are focused on elimination of senescent cell functions in three main ways: i) use of senolytics; ii) inhibition of SASP; and iii) improvement of immune system functions against senescent cells (immunosurveillance). In addition, some anti-cancer therapies are based on the induction of senescence in tumor cells. However, these senescent-like cancer cells must be subsequently cleared to avoid a chronic pro-tumorigenic state. Here is a summary of different scenarios, depending on the therapy used, with a discussion of the pros and cons of each scenario.

Post-stroke inflammation-target or tool for therapy?

Inflammation is currently considered a prime target for the development of new stroke therapies. In the acute phase of ischemic stroke, microglia are activated and then circulating immune cells invade the peri-infarct and infarct core. Resident and infiltrating cells together orchestrate the post-stroke inflammatory response, communicating with each other and the ischemic neurons, through soluble and membrane-bound signaling molecules, including cytokines. Inflammation can be both detrimental and beneficial at particular stages after a stroke. While it can contribute to expansion of the infarct, it is also responsible for infarct resolution, and influences remodeling and repair. Several pre-clinical and clinical proof-of-concept studies have suggested the effectiveness of pharmacological interventions that target inflammation post-stroke. Experimental evidence shows that targeting certain inflammatory cytokines, such as tumor necrosis factor, interleukin (IL)-1, IL-6, and IL-10, holds promise. However, as these cytokines possess non-redundant protective and immunoregulatory functions, their neutralization or augmentation carries a risk of unwanted side effects, and clinical translation is, therefore, challenging. This review summarizes the cell biology of the post-stroke inflammatory response and discusses pharmacological interventions targeting inflammation in the acute phase after a stroke that may be used alone or in combination with recanalization therapies. Development of next-generation immune therapies should ideally aim at selectively neutralizing pathogenic immune signaling, enhancing tissue preservation, promoting neurological recovery and leaving normal function intact.

Humanization of Antibodies using a Statistical Inference Approach

Antibody humanization is a key step in the preclinical phase of the development of therapeutic antibodies, originally developed and tested in non-human models (most typically, in mouse). The standard technique of Complementarity-Determining Regions (CDR) grafting into human Framework Regions of germline sequences has some important drawbacks, in that the resulting sequences often need further back-mutations to ensure functionality and/or stability. Here we propose a new method to characterize the statistical distribution of the sequences of the variable regions of human antibodies, that takes into account phenotypical correlations between pairs of residues, both within and between chains. We define a "humanness score" of a sequence, comparing its performance in distinguishing human from murine sequences, with that of some alternative scores in the literature. We also compare the score with the experimental immunogenicity of clinically used antibodies. Finally, we use the humanness score as an optimization function and perform a search in the sequence space, starting from different murine sequences and keeping the CDR regions unchanged. Our results show that our humanness score outperforms other methods in sequence classification, and the optimization protocol is able to generate humanized sequences that are recognized as human by standard homology modelling tools.

Interleukin-6: designing specific therapeutics for a complex cytokine

Interleukin-6 (IL-6) is a pivotal cytokine with a diverse repertoire of physiological functions that include regulation of immune cell proliferation and differentiation. Dysregulation of IL-6 signalling is associated with inflammatory and lymphoproliferative disorders such as rheumatoid arthritis and Castleman disease, and several classes of therapeutics have been developed that target components of the IL-6 signalling pathway. So far, monoclonal antibodies against IL-6 or IL-6 receptor (IL-6R) and Janus kinases (JAK) inhibitors have been successfully developed for the treatment of autoimmune diseases such as rheumatoid arthritis. However, clinical trials of agents targeting IL-6 signalling have also raised questions about the diseases and patient populations for which such agents have an appropriate benefit-risk profile. Knowledge from clinical trials and advances in our understanding of the complexities of IL-6 signalling, including the potential to target an IL-6 trans-signalling pathway, are now indicating novel opportunities for therapeutic intervention. In this Review, we overview the roles of IL-6 in health and disease and analyse progress with several approaches of inhibiting IL-6-signalling, with the aim of illuminating when and how to apply IL-6 blockade.

Regulatory effect of anti-gp130 functional mAb on IL-6 mediated RANKL and Wnt5a expression through JAK-STAT3 signaling pathway in FLS

We investigated the effect on rheumatoid arthritis (RA) of an anti-gp130 monoclonal antibody (mAb) and its mechanism using RA fibroblast-like synoviocytes (FLS) and a collagen antibody–induced arthritis (CAIA) mouse model. We determined the interleukin 6 (IL-6), IL-6 receptor α (IL-6Rα), gp130, receptor activator of nuclear factor κB ligand (RANKL), matrix metalloproteinase 3 (MMP3), TIMP metallopeptidase inhibitor 1 (TIMP1), and Bcl-2 levels in RA and osteoarthritis (OA) serum and synovial fluid. RA FLS were cultured with or without IL-6/IL-6Rα; WNT5A and RANKL levels were detected. We generated an anti-gp130 mAb (M10) with higher affinity and specificity, blocked IL-6 signaling with it, and assessed its effects on the CAIA model, WNT5A and RANKL expression, and signal transducer and activator of transcription 3 (STAT3) phosphorylation. The IL-6 signaling system in patients with RA was increased; RANKL, MMP3, TIMP1, and Bcl-2 in RA bone were elevated. IL-6/IL-6Rα increased RA FLS WNT5A and RANKL expression. M10 ameliorated arthritis in the CAIA model, and inhibited RANKL, WNT5A, and Bcl-2 expression in RA FLS by blocking IL-6 signaling, likely via Janus kinase–STAT3 pathway downregulation. The IL-6–soluble IL-6Rα–gp130 complex is hyperactive in RA and OA. M10 may be the basis for a novel RA treatment drug.

Potential therapeutic implications of IL-6/IL-6R/gp130-targeting agents in breast cancer

Interleukin-6 (IL-6) is a pleiotropic cytokine with known multiple functions in immune regulation, inflammation, and oncogenesis. Binding of IL-6 to the IL-6 receptor (IL-6R) induces homodimerization and recruitment of glycoprotein 130 (gp130), which leads to activation of downstream signaling. Emerging evidence suggests that high levels of IL-6 are correlated with poor prognosis in breast cancer patients. IL-6 appears to play a critical role in the growth and metastasis of breast cancer cells, renewal of breast cancer stem cells (BCSCs), and drug resistance of BCSCs, making anti-IL-6/IL-6R/gp130 therapies promising options for the treatment and prevention of breast cancers. However, preclinical and clinical studies of the applications of anti-IL-6/IL-6R/gp130 therapy in breast cancers are limited. In this review, we summarize the structures, preclinical and clinical studies, mechanisms of action of chemical and biological blockers that directly bind to IL-6, IL-6R, or gp130, and the potential clinical applications of these pharmacological agents as breast cancer therapies.

The Innate and Adaptive Immune System as Targets for Biologic Therapies in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is an immune-mediated inflammatory condition causing inflammation of gastrointestinal and systemic cells, with an increasing prevalence worldwide. Many factors are known to trigger and maintain inflammation in IBD including the innate and adaptive immune systems, genetics, the gastrointestinal microbiome and several environmental factors. Our knowledge of the involvement of the immune system in the pathophysiology of IBD has advanced rapidly over the last two decades, leading to the development of several immune-targeted treatments with a biological source, known as biologic agents. The initial focus of these agents was directed against the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) leading to dramatic changes in the disease course for a proportion of patients with IBD. However, more recently, it has been shown that a significant proportion of patients do not respond to anti-TNF-α directed therapies, leading a shift to other inflammatory pathways and targets, including those of both the innate and adaptive immune systems, and targets linking both systems including anti-leukocyte trafficking agents-integrins and adhesion molecules. This review briefly describes the molecular basis of immune based gastrointestinal inflammation in IBD, and then describes how several current and future biologic agents work to manipulate these pathways, and their clinical success to date.

Targeting interleukin-6 in autoimmune uveitis

Interleukin-6 (IL-6) is a key cytokine that is strongly up-regulated during infection and inflammation. Featuring pleiotropic activity, IL-6 is responsible for the induction of hepatic acute-phase proteins, trafficking of acute and chronic inflammatory cells, differentiation of adaptive T cell responses, homeostatic regulation, and tissue regeneration. Dysregulated IL-6 production has been associated with the development of a wide variety of systemic immune-mediated, chronic diseases, and even certain types of cancer. From the ocular perspective, significant elevation of IL-6 has been found in ocular fluids derived from diabetic macular edema, retinal vein occlusion, and refractory/chronic uveitis patients. During the last decade, tocilizumab, a neutralizing monoclonal antibody (mAb) that targets the IL-6 receptor (IL-6R), has been approved for the treatment of rheumatoid arthritis in >100 countries worldwide. Furthermore, it has been reported to be effective for the treatment of a number of autoimmune diseases including uveitis and its associated macular edema. Currently numerous candidate molecular strategies targeting the IL-6 signaling pathways are in progress through clinical trials in various disorders. Herein we discuss the basic biology of IL-6 and its pathological role in the development of immune-mediated conditions, particularly focusing on inflammatory eye diseases. It also provides an overview of the on-going clinical trials with the new anti-IL-6 mAbs and their potential use in the clinical practice.

Anti-Interleukin-6 Promotes Allogeneic Bone Marrow Engraftment and Prolonged Graft Survival in an Irradiation-Free Murine Transplant Model

Transfer of recipient regulatory T cells (Tregs) induces mixed chimerism and tolerance in an irradiation-free bone marrow (BM) transplantation (BMT) model involving short-course co-stimulation blockade and mTOR inhibition. Boosting endogenous Tregs pharmacologically in vivo would be an attractive alternative avoiding the current limitations of performing adoptive cell therapy in the routine clinical setting. Interleukin-6 (IL-6) potently inhibits Treg differentiation and its blockade was shown to increase Treg numbers in vivo. Therefore, we investigated whether IL-6 blockade can replace adoptive Treg transfer in irradiation-free allogeneic BMT. Treatment with anti-IL-6 instead of Treg transfer led to multi-lineage chimerism (persisting for ~12 weeks) in recipients of fully mismatched BM and significantly prolonged donor skin (MST 58 days) and heart (MST > 100 days) graft survival. Endogenous Foxp3⁺ Tregs expanded in anti-IL-6-treated BMT recipients, while dendritic cell (DC) activation and memory CD8⁺ T cell development were inhibited. Adding anti-IL-17 to anti-IL-6 treatment increased Treg frequencies, but did not further prolong donor skin graft survival significantly. These results demonstrate that IL-6 blockade promotes BM engraftment and donor graft survival in non-irradiated recipients and might provide an alternative to Treg cell therapy in the clinical setting.