Certolizumab Pegol: A Review in Inflammatory Autoimmune Diseases

Infection toxicity assessment of tumor necrosis factor α inhibitors in the treatment of IBD: a real-world study based on the US food and drug administration adverse events reporting system (FAERS)

BACKGROUND

Tumor necrosis factor α (TNF-α) inhibitors are widely used to treat inflammatory bowel disease (IBD), but systematic risk assessment of infectious toxicity is still lacking.

RESEARCH DESIGN AND METHODS

We used disproportional analysis to calculate infection-related risk signals for four TNF-α inhibitors and compared them with infection-related signals for seven other therapies.

RESULTS

There were 55,379 reports of infection-related adverse events (AEs) with TNF-α inhibitors as a 'primary suspect (PS)' therapy. The median time to onset of infection-related AEs was 113 days (interquartile range [IQR] 14-612). TNF-α inhibitors present the strongest infectious toxic signal than interleukin 12/23 (IL-12/23) inhibitors, integrin blockers, Jak inhibitors, and S1P receptor modulator. Compared with infliximab, certolizumab pegol, and adalimumab, golimumab showed the strongest signal. The strongest signal corresponding to appendicitis, pulmonary tuberculosis, pneumonia, sepsis, urinary tract infection, otitis media and herpes zoster is golimumab, infliximab, golimumab, natalizumab, certolizumab pegol, infliximab, and infliximab.

CONCLUSIONS

Compared with other control therapies, TNF-α inhibitors have the strongest infectious toxicity signal. Compared with other TNF-α inhibitors, golimumab has the strongest infectious toxicity signal. When using TNF-α inhibitors to treat IBD, infection-related AEs should be vigilant.

A Case of Rectus Sheath Hematoma Caused by Self-Injection of Certolizumab Pegol

Rectus sheath hematoma (RSH) is a condition caused by hemorrhage into the rectus sheath. A 61-year-old man with end-stage renal failure and rheumatoid arthritis presented to our hospital with abdominal pain. The patient had been receiving biweekly self-injections of certolizumab pegol to the abdominal wall. Computed tomography (CT) demonstrated a large high-density left-sided RSH. Abdominal pain gradually exacerbated; thus, transcatheter arterial embolization (TAE) for the left inferior epigastric artery (IEA) was performed. This is the first reported case of RSH caused by certolizumab pegol. Factors contributing to RSH include low abdominal wall fat, the use of auto-injector-based preparations, and anticoagulant use in dialysis.

Pathophysiology and Treatment of Psoriasis: From Clinical Practice to Basic Research

Psoriasis, a chronic inflammatory dermatosis, represents a significant clinical challenge due to its complex pathogenesis and the limitations of existing therapeutic strategies. Current psoriasis diagnoses are primarily clinician-dependent, with instrumental diagnostics serving as adjuncts. Ongoing research is progressively deciphering its molecular underpinnings; the future of psoriasis diagnostics may involve genetic and immunological profiling to pinpoint biomarkers, enabling more accurate and timely interventions. The administration of psoriasis medications, whether oral, injectable, or topical, is associated with a range of side effects and compliance issues. Topical medications, despite their advantages in patient compliance and reduced systemic side effects, are hindered by the altered skin barrier in psoriasis, which impedes effective drug penetration and retention. In recent years, the development of novel transdermal drug delivery systems represents a promising frontier in psoriasis management. Nanotechnology-, microneedle- and dressing-based systems have demonstrated the potential for improved skin penetration, enhanced bioavailability, or extended retention time. Here, we will focus on the latest insights into the etiology, diagnostic methodologies, and therapeutic approaches for psoriasis, with a particular emphasis on the evolution and challenges of novel transdermal drug delivery systems.

Biological therapy for psoriatic arthritis: current state and future perspectives

Psoriatic arthritis is a medical condition that lies at the intersection of various fields of medicine, and its therapy always requires a comprehensive, holistic approach. Biological disease-modifying antirheumatic drugs (bDMARDs) constitute an extremely effective treatment method for PsA, provided that appropriate principles for patient qualification for the drug are followed, along with subsequent monitoring of the response to treatment. Based on their mechanisms of action, four main groups of bDMARDs used in PsA can be distinguished (TNF inhibitors, IL-12/23 and IL-23 inhibitors, IL-17 inhibitors, CTLA4 agonists). Clinical trials are ongoing in search of registration for additional bDMARDs, and the tasks for doctors and scientists worldwide include patient education, increasing treatment accessibility, and optimizing its costs.

Towards a structural and functional analysis of the immunoglobulin-fold proteome

The immunoglobulin fold (Ig fold) domain is a super-secondary structural motif consisting of a sandwich with two layers of β-sheets that is present in many proteins with very diverse biological functions covering a wide range of physiological processes. This domain presents a modular architecture built with β strands connected by variable length loops that has a highly conserved structural core of four β-strands and quite variable β-sheet extensions in the two sandwich layers that enable both divergent and convergent evolutionary mechanisms in the known Ig fold proteome. The central role of this Ig fold's structural plasticity in the evolutionary success of antibodies in our immune system is well established. Nature has also utilized this Ig fold in all domains of life in many different physiological contexts that go way beyond the immune system. Here we will present a structural and functional overview of the utilization of the Ig fold in different biological processes and in different cellular contexts to highlight some of the innumerable ways that this structural motif can interact in multidomain proteins to enable their diversity of functions. This includes shareable specific protein structure visualizations behind those functions that serve as starting points for further explorations of the biomolecular interactions spanning the Ig fold proteome. This overview also highlights how this Ig fold is being utilized through natural adaptation, engineering, and even building from scratch for a range of biotechnological applications.

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.

Anti-Drug Antibodies in the Biological Therapy of Autoimmune Rheumatic Diseases

Autoimmune rheumatic diseases are a cluster of heterogeneous disorders that share some clinical symptoms such as pain, tissue damage, immune deregulation, and the presence of inflammatory mediators. Biologic disease-modifying antirheumatic drugs are some of the most effective treatments for rheumatic diseases. However, their molecular and pharmacological complexity makes them potentially immunogenic and capable of inducing the development of anti-drug antibodies. TNF inhibitors appear to be the main contributors to immunogenicity because they are widely used, especially in rheumatoid arthritis. Immunogenicity response on these treatments is crucial since the appearance of ADAs has consequences in terms of safety and efficacy. Therefore, this review proposes an overview of the immunogenicity of biological agents used in autoimmune rheumatic diseases highlighting the prevalence of anti-drug antibodies.

Combining nanotechnology with monoclonal antibody drugs for rheumatoid arthritis treatments

Rheumatoid arthritis (RA) is a systemic immune disease characterized by synovial inflammation. Patients with RA commonly experience significant damage to their hand and foot joints, which can lead to joint deformities and even disability. Traditional treatments have several clinical drawbacks, including unclear pharmacological mechanisms and serious side effects. However, the emergence of antibody drugs offers a promising approach to overcome these limitations by specifically targeting interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and other cytokines that are closely related to the onset of RA. This approach reduces the incidence of adverse effects and contributes to significant therapeutic outcomes. Furthermore, combining these antibody drugs with drug delivery nanosystems (DDSs) can improve their tissue accumulation and bioavailability.Herein, we provide a summary of the pathogenesis of RA, the available antibody drugs and DDSs that improve the efficacy of these drugs. However, several challenges need to be addressed in their clinical applications, including patient compliance, stability, immunogenicity, immunosupression, target and synergistic effects. We propose strategies to overcome these limitations. In summary, we are optimistic about the prospects of treating RA with antibody drugs, given their specific targeting mechanisms and the potential benefits of combining them with DDSs.

Therapeutic Antibodies: An Overview

Polyclonal immunoglobulin (Ig) preparations have been used for several decades for treatment of primary and secondary immunodeficiencies and for treatment of some infections and intoxications. This has demonstrated the importance of Igs, also called antibodies (Abs) for prevention and elimination of infections. Moreover, elucidation of the structure and functions of Abs has suggested that they might be useful for targeted treatment of several diseases, including cancers and autoimmune diseases. The development of technologies for production of specific monoclonal Abs (MAbs) in large amounts has led to the production of highly effective therapeutic antibodies (TAbs), a collective term for MAbs (MAbs) with demonstrated clinical efficacy in one or more diseases. The number of approved TAbs is currently around hundred, and an even larger number is under development, including several engineered and modified Ab formats. The use of TAbs has provided new treatment options for many severe diseases, but prediction of clinical effect is difficult, and many patients eventually lose effect, possibly due to development of Abs to the TAbs or to other reasons. The therapeutic efficacy of TAbs can be ascribed to one or more effects, including binding and neutralization of targets, direct cytotoxicity, Ab-dependent complement-dependent cytotoxicity, Ab-dependent cellular cytotoxicity or others. The therapeutic options for TAbs have been expanded by development of several new formats of TAbs, including bispecific Abs, single domain Abs, TAb-drug conjugates, and the use of TAbs for targeted activation of immune cells. Most promisingly, current research and development can be expected to increase the number of clinical conditions, which may benefit from TAbs.

Autoinflammatory Diseases and Cytokine Storms-Imbalances of Innate and Adaptative Immunity

Innate and adaptive immune responses have a well-known link and represent the distinctive origins of several diseases, many of which may be the consequence of the loss of balance between these two responses. Indeed, autoinflammation and autoimmunity represent the two extremes of a continuous spectrum of pathologic conditions with numerous overlaps in different pathologies. A common characteristic of these dysregulations is represented by hyperinflammation, which is an exaggerated response of the immune system, especially involving white blood cells, macrophages, and inflammasome activation with the hyperproduction of cytokines in response to various triggering stimuli. Moreover, hyperinflammation is of great interest, as it is one of the main manifestations of COVID-19 infection, and the cytokine storm and its most important components are the targets of the pharmacological treatments used to combat COVID-19 damage. In this context, the purpose of our review is to provide a focus on the pathogenesis of autoinflammation and, in particular, of hyperinflammation in order to generate insights for the identification of new therapeutic targets and strategies.

Tumor necrosis factor inhibitors as therapeutic agents for recurrent spontaneous abortion (Review)

Recurrent spontaneous abortion (RSA) is a troublesome pregnancy disorder that manifests as sequential early pregnancy losses; its causes are diverse and complex. Among the known possible causes of RSA, the development of an immune disorder in response to the embryo appears to be the most pronounced. The imbalance between immune rejection and immune tolerance contributes to pregnancy loss in females with RSA, wherein the abnormal ratio of T helper (Th)1 cell‑related cytokines [predominantly tumor necrosis factor (TNF)‑α] and Th2 cell‑related cytokines is a strong risk factor for RSA. TNF‑α is a pro‑inflammatory cytokine and TNF inhibitors have been effective in the treatment of various autoimmune diseases, such as ankylosing spondylitis, and inflammatory diseases, such as ulcerative colitis. Based on their immunomodulatory properties, TNF inhibitors have been used in the treatment of RSA to reduce the immune rejection rate and improvement in pregnancy outcomes has been observed in females suffering from RSA who were treated with TNF inhibitors. The aim of the present review was to interpret the involvement of TNF‑α in the immunological disorder underlying RSA and summarize the clinical outcomes of TNF inhibitor treatment in patients with RSA.

Perspectives on passive antibody therapy and peptide-based vaccines against emerging pathogens like SARS-CoV-2

The current epidemic of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is raising awareness of the need to act faster when dealing with new pathogens. Exposure to an emerging pathogen generates an antibody response that can be used for preventing and treating the infection. These antibodies might have a high specificity to a target, few side effects, and are useful in the absence of an effective vaccine for treating immunocompromised individuals. The approved antibodies against the receptor-binding domain (RBD) of the viral spike protein of SARS-CoV-2 (e.g., regdanvimab, bamlanivimab, etesevimab, and casirivimab/imdevimab) have been selected from the antibody repertoire of B cells from convalescent patients using flow cytometry, next-generation sequencing, and phage display. This encourages use of these techniques especially phage display, because it does not require expensive types of equipment and can be performed on the lab bench, thereby making it suitable for labs with limited resources. Also, the antibodies in blood samples from convalescent patients can be used to screen pre-made peptide libraries to identify epitopes for vaccine development. Different types of vaccines against SARS-CoV-2 have been developed, including inactivated virus vaccines, mRNA-based vaccines, non-replicating vector vaccines, and protein subunits. mRNA vaccines have numerous advantages over existing vaccines, such as efficacy, ease of manufacture, safety, and cost-effectiveness. Additionally, epitope vaccination may constitute an attractive strategy to induce high levels of antibodies against a pathogen and phages might be used as immunogenic carriers of such peptides. This is a point worth considering further, as phage-based vaccines have been shown to be safe in clinical trials and phages are easy to produce and tolerate high temperatures. In conclusion, identification of the antibody repertoire of recovering patients, and the epitopes they recognize, should be an attractive alternative option for developing therapeutic and prophylactic antibodies and vaccines against emerging pathogens.

Certolizumab Pegol: A Review in Moderate to Severe Plaque Psoriasis

Certolizumab pegol (Cimzia^®) is a PEGylated, Fab'-only, recombinant humanized antibody against TNF-α. Subcutaneous certolizumab pegol is indicated for the treatment of various immune-mediated inflammatory diseases (IMIDs), including moderate to severe plaque psoriasis. In pivotal phase III trials in adults with moderate to severe plaque psoriasis, significantly more patients receiving certolizumab pegol 200 mg or 400 mg once every 2 weeks than placebo recipients achieved a ≥ 75% reduction in PASI score (PASI75 responder) and a PGA score of clear/mostly clear with a ≥ 2 point improvement from baseline (PGA0/1 responder) at week 12 (CIMPACT) or 16 (CIMPASI-1 and -2). In CIMPACT, certolizumab pegol 400 mg once every 2 weeks was superior to etanercept (highest recommended dosage) at 12 weeks, with certolizumab pegol 200 mg once every 2 weeks demonstrating non-inferiority, but not superiority, to etanercept. The clinical benefits of certolizumab pegol were maintained during the maintenance phase (to week 48) and the open-label extension phase of these trials. Certolizumab pegol is unique among the biologics, with the absence of an Fc fragment conferring pharmacokinetic advantages; most notably, its minimal transfer across the placenta, and low relative infant dose during breastfeeding in conjunction with its low oral bioavailability. Certolizumab pegol was generally well tolerated and no new safety signals were identified in these phase III trials, which complements its established safety profile in other IMIDs. Certolizumab pegol is a useful option for the treatment of moderate to severe plaque psoriasis and provides an important treatment option for women of childbearing age, for whom there are limited options available.

Clinical Practice of Adalimumab and Infliximab Biosimilar Treatment in Adult Patients With Crohn's Disease

The introduction of tumor necrosis factor (TNF) inhibitors has significantly changed the treatment landscape in Crohn's disease (CD). The overall therapeutic achievements with TNF inhibitors such as infliximab, adalimumab, and certolizumab pegol paved the way to push the boundaries of treatment goals beyond symptomatic relief and toward cessation of objective signs of inflammation, including endoscopic remission. Even though these agents are widely used for the treatment of moderate to severe CD, heterogeneity still exists in translating evidence-based guidelines on the use of anti-TNF agents into actual treatment algorithms in CD. This might be due to several reasons including disparities in health expenditure policies; lack of harmonization between countries; and variations in assessment of disease severity, use of disease monitoring tools, or application of treatment targets by physicians. With the advent of biosimilars, patent-free versions of reference biologics are now available to minimize health inequalities in drug availability. In this context, this article aims to provide practical clinical guidance for the use of infliximab and adalimumab biosimilars in patients with moderate to severe CD by outlining different clinical scenarios that patients may encounter during their treatment journey.

Simultaneous bilateral aqueous misdirection following certolizumab therapy for rheumatoid arthritis

Aqueous misdirection syndrome is a rare, incompletely understood, sight-threatening eye condition that is difficult to diagnose and treat. We present a case of simultaneous bilateral aqueous misdirection following the administration of certolizumab in a 41-year-old women with rheumatoid arthritis and no known risk factors. To our knowledge, aqueous misdirection has not previously been associated with the use of tumour necrosis factor-alpha inhibitors.

Anti-TNF, a magic bullet in cancer immunotherapy?

Immune checkpoint blockers (ICB) have revolutionized cancer therapy. However, complete response is observed in a minority of patients and most patients develop immune-related adverse events (irAEs). These include colitis, which can be treated with anti-tumor necrosis factor (TNF) antibodies such as Infliximab. In a recent issue of the Journal for ImmunoTherapy of Cancer, Badran et al. reported that co-administering Infliximab together with ICB to five cancer patients prevents colitis recurrence, with four of them exhibiting overall disease stability. The basis for this treatment strategy stemmed from our pre-clinical demonstration that TNF contributes to resistance to anti-PD-1 therapy. In agreement with this concept, we have shown that TNF blockers improve the anti-tumor therapeutic activity of ICB in mice and based on these findings we are currently evaluating the combination in melanoma patients enrolled in the TICIMEL clinical trial. Herein, (i) we discuss the scientific rationale for combining anti-TNF and ICB in cancer patients, (ii) comment on the paper published by Badran et al. and (iii) provide the TICIMEL clinical trial design.

Anti-Tumor Necrosis Factor α Therapeutics Differentially Affect Leishmania Infection of Human Macrophages

Tumor necrosis factor α (TNFα) drives the pathophysiology of human autoimmune diseases and consequently, neutralizing antibodies (Abs) or Ab-derived molecules directed against TNFα are essential therapeutics. As treatment with several TNFα blockers has been reported to entail a higher risk of infectious diseases such as leishmaniasis, we established an in vitro model based on Leishmania-infected human macrophages, co-cultured with autologous T-cells, for the analysis and comparison of anti-TNFα therapeutics. We demonstrate that neutralization of soluble TNFα (sTNFα) by the anti-TNFα Abs Humira^®, Remicade^®, and its biosimilar Remsima^® negatively affects infection as treatment with these agents significantly reduces Leishmania-induced T-cell proliferation and increases the number of infected macrophages. By contrast, we show that blockade of sTNFα by Cimzia^® does not affect T-cell proliferation and infection rates. Moreover, compared to Remicade^®, treatment with Cimzia^® does not impair the expression of cytolytic effector proteins in proliferating T-cells. Our data demonstrate that Cimzia^® supports parasite control through its conjugated polyethylene glycol (PEG) moiety as PEGylation of Remicade^® improves the clearance of intracellular Leishmania. This effect can be linked to complement activation, with levels of complement component C5a being increased upon treatment with Cimzia^® or a PEGylated form of Remicade^®. Taken together, we provide an in vitro model of human leishmaniasis that allows direct comparison of different anti-TNFα agents. Our results enhance the understanding of the efficacy and adverse effects of TNFα blockers and they contribute to evaluate anti-TNFα therapy for patients living in countries with a high prevalence of leishmaniasis.

In Vivo PET Imaging of the Activated Immune Environment in a Small Animal Model of Inflammatory Arthritis

BACKGROUND

Evolving immune-mediated therapeutic strategies for rheumatoid arthritis (RA) may benefit from an improved understanding of the complex role that T-cell activation plays in RA. This study assessed the potential of fluorine-18-labeled 9-β-d-arabinofuranosylguanine ([¹⁸F]F-AraG) positron emission tomography (PET) imaging to report immune activation in vivo in an adjuvant-induced arthritis (AIA) small animal model.

METHODS

Using positron emission tomography-computed tomography imaging, uptake of [¹⁸F]F-AraG in the paws of mice affected by arthritis at 6 (acute) and 20 (chronic) days following AIA induction in a single paw was assessed and compared to uptake in contralateral control paws. Fractions of T cells and B cells demonstrating markers of activation at the 2 time points were determined by flow cytometry.

RESULTS

Differential uptake of [¹⁸F]F-AraG was demonstrated on imaging of the affected joint when compared to control at both acute and chronic time points with corresponding changes in markers of T-cell activation observed on flow cytometry.

CONCLUSION

[¹⁸F]F-AraG may serve as an imaging biomarker of T-cell activation in inflammatory arthritis. Further development of this technique is warranted and could offer a tool to explore the temporal link between activated T cells and RA as well as to monitor immune-mediated therapies for RA in clinical trials.

Role of biologics and biosimilars in inflammatory bowel disease: current trends and future perspectives

Inflammatory bowel disease (IBD) is an idiopathic chronic inflammatory disease of the gastrointestinal system. The spectrum is of predominantly two types, namely, ulcerative colitis and Crohn’s disease. The incidence of IBD has been increasing steadily since 1990, and so the number of agents used in their treatment. Biologics that are derived partly or completely from living biological sources such as animals and humans have become widely available, which provide therapeutic benefits to the IBD patients. Currently, monoclonal antibodies against tumor necrosis factor-alpha (infliximab, adalimumab, certolizumab, and golimumab), integrins (vedolizumab and natalizumab), and interleukin (IL)-12 and IL-23 antagonists (ustekinumab) are approved for use in IBD. Biosimilars of infliximab and adalimumab are also available for the treatment of IBD. This review summarizes the clinical pharmacology, studies leading to their approval, overall indications and their use in IBD, usage in pregnancy and lactation, and the adverse effects of these agents. This review also summarizes the recent advances and future perspectives specific to biologics and biosimilars in IBD.

Structural Biology of the TNFα Antagonists Used in the Treatment of Rheumatoid Arthritis

The binding of the tumor necrosis factor α (TNFα) to its cognate receptor initiates many immune and inflammatory processes. The drugs, etanercept (Enbrel^®), infliximab (Remicade^®), adalimumab (Humira^®), certolizumab-pegol (Cimzia^®), and golimumab (Simponi^®), are anti-TNFα agents. These drugs block TNFα from interacting with its receptors and have enabled the development of breakthrough therapies for the treatment of several autoimmune inflammatory diseases, including rheumatoid arthritis, Crohn's disease, and psoriatic arthritis. In this review, we describe the latest works on the structural characterization of TNFα-TNFα antagonist interactions related to their therapeutic efficacy at the atomic level. A comprehensive comparison of the interactions of the TNFα blockers would provide a better understanding of the molecular mechanisms by which they neutralize TNFα. In addition, an enhanced understanding of the higher order complex structures and quinary structures of the TNFα antagonists can support the development of better biologics with the improved pharmacokinetic properties. Accumulation of these structural studies can provide a basis for the improvement of therapeutic agents against TNFα for the treatment of rheumatoid arthritis and other autoimmune inflammatory diseases in which TNFα plays an important role in pathogenesis.

Drugs for Autoimmune Inflammatory Diseases: From Small Molecule Compounds to Anti-TNF Biologics

Although initially described as an anti-tumor mediator, tumor necrosis factor-alpha (TNF) is generally considered as the master pro-inflammatory cytokine. It plays a crucial role in the pathogenesis of inflammatory diseases, such as rheumatoid arthritis (RA), inflammatory bowel disease, ankylosing spondylitis (AS), and psoriasis. Consequently, anti-TNF therapy has become mainstay treatment for autoimmune diseases. Historically, anti-inflammatory agents were developed before the identification of TNF. Salicylates, the active components of Willow spp., were identified in the mid-19th century for the alleviation of pain, fever, and inflammatory responses. Study of this naturally occurring compound led to the discovery of aspirin, which was followed by the development of non-steroidal anti-inflammatory drugs (NSAIDs) due to the chemical advances in the 19th–20th centuries. Initially, the most of NSAIDs were organic acid, but the non-acidic compounds were also identified as NSAIDs. Although effective in the treatment of inflammatory diseases, NSAIDs have some undesirable and adverse effect, such as ulcers, kidney injury, and bleeding in the gastrointestinal tract. In the past two decades, anti-TNF biologics were developed. Drugs belong to this class include soluble TNF receptor 2 fusion protein and anti-TNF antibodies. The introduction of anti-TNF therapeutics has revolutionized the management of autoimmune diseases, such as RA, psoriatic arthritis (PsA), plaque psoriasis (PP), AS, CD and ulcerative colitis (UC). Nevertheless, up to 40% of patients have no response to anti-TNF treatment. Furthermore, this treatment is associated with some adverse effects such as increased risk of infection, and even triggered the de novo development of autoimmune diseases. Such harmful effect of anti-TNF treatment is likely caused by the global inhibition of TNF biological functions. Therefore, specific inhibition of TNF receptor (TNFR1 or TNFR2) may represent a safer and more effective treatment, as proposed by some recent studies. In this review article, the historical development of anti-inflammatory drugs after World War II as briefly described above will be reviewed and analyzed. The future trend in the development of novel TNF receptor-targeting therapeutics will be discussed in the context of latest progress in the research of TNF biology.

Current and emerging therapeutic targets for IBD

Various therapeutic advances have led to a paradigm shift in the clinical management of patients with IBD. The introduction of immunosuppressive (such as azathioprine) and biologic agents (such as TNF blockers) has markedly reduced the need to use corticosteroids for therapy. Furthermore, the α4β7 integrin blocker vedolizumab has been introduced for clinical IBD therapy. Moreover, various new inhibitors of cytokines (for example, IL-6-IL-6R and IL-12-IL-23 blockers or apremilast), modulators of cytokine signalling events (for example, JAK inhibitors or SMAD7 blocker), inhibitors of transcription factors (for example, GATA3 or RORγt) and new anti-adhesion and anti-T-cell-activation and migration strategies (for example, β7 integrin, sphingosine 1-phosphate receptors and MAdCAM1 inhibitors, regulatory T-cell therapy and stem cells) are currently being evaluated in controlled clinical trials. This Review aims to provide a comprehensive overview about current and future therapeutic approaches for IBD therapy. Furthermore, potential mechanisms of action of these therapeutic approaches and their implications for clinical therapy in IBD are discussed.

Molecular Basis for the Neutralization of Tumor Necrosis Factor α by Certolizumab Pegol in the Treatment of Inflammatory Autoimmune Diseases

Monoclonal antibodies against TNFα, including infliximab, adalimumab, golimumab, and certolizumab pegol, are widely used for the treatment of the inflammatory diseases such as rheumatoid arthritis and inflammatory bowel disease. Recently, the crystal structures of TNFα, in complex with the Fab fragments of infliximab and adalimumab, have revealed the molecular mechanisms of these antibody drugs. Here, we report the crystal structure of TNFα in complex with the Fab fragment of certolizumab pegol to clarify the precise antigen-antibody interactions and the structural basis for the neutralization of TNFα by this therapeutic antibody. The structural analysis and the mutagenesis study revealed that the epitope is limited to a single protomer of the TNFα trimer. Additionally, the DE loop and the GH loop of TNFα play critical roles in the interaction with certolizumab, suggesting that this drug exerts its effects by partially occupying the receptor binding site of TNFα. In addition, a conformational change of the DE loop was induced by certolizumab binding, thereby interrupting the TNFα-receptor interaction. A comprehensive comparison of the interactions of TNFα blockers with TNFα revealed the epitope diversity on the surface of TNFα, providing a better understanding of the molecular mechanism of TNFα blockers. The accumulation of these structural studies can provide a basis for the improvement of therapeutic antibodies against TNFα.