Advances in use of immunomodulatory agents--a rheumatology perspective

Engineering antigen-presenting cells for immunotherapy of autoimmunity

Autoimmune diseases are burdensome conditions that affect a significant fraction of the global population. The hallmark of autoimmune disease is a host's immune system being licensed to attack its tissues based on specific antigens. There are no cures for autoimmune diseases. The current clinical standard for treating autoimmune diseases is the administration of immunosuppressants, which weaken the immune system and reduce auto-inflammatory responses. However, people living with autoimmune diseases are subject to toxicity, fail to mount a sufficient immune response to protect against pathogens, and are more likely to develop infections. Therefore, there is a concerted effort to develop more effective means of targeting immunomodulatory therapies to antigen-presenting cells, which are involved in modulating the immune responses to specific antigens. In this review, we highlight approaches that are currently in development to target antigen-presenting cells and improve therapeutic outcomes in autoimmune diseases.

Dereplication and quantification of the ethanol extract of Miconia albicans (Melastomaceae) by HPLC-DAD-ESI-/MS/MS, and assessment of its anti-hyperalgesic and anti-inflammatory profiles in a mice arthritis-like model: Evidence for involvement of TNF-α, IL-1β and IL-6

ETHNOPHARMACOLOGICAL RELEVANCE

Miconia albicans (Sw) Triana (Melastomataceae), a medicinal plant widely used by practitioners of folk medicine in the northeast of Brazil, has been used to treat chronic inflammatory disorders, such as rheumatoid arthritis (RA) and other joint conditions. Oddly, there is little research on the species.

AIM OF THE STUDY

We aimed to evaluate the anti-arthritic and anti-inflammatory profile of the ethanolic leaf extract of M. albicans (EEMA), as well as to perform dereplication and quantification by HPLC-DAD-ESI-/MS/MS.

MATERIALS AND METHODS

The compounds present in the extracts were identified by HPLC-DAD-ESI-MS/MS. The possible anti-inflammatory effect of EEMA (50 and 100 mg/kg, p.o) was evaluated using the pleurisy model induced by carrageenan and its action on IL-1β and TNF-α levels was also evaluated. The RA model was induced through the intra-articular injection of complete Freund's adjuvant (CFA).

RESULTS

HPLC-DAD-ESI-MS/MS analysis identified 23 compounds, with glycoside flavonoids mainly derived from quercetin, and rutin being the main compounds. EEMA significantly reduced (p < 0.001) leukocyte migration in the pleurisy model and reduced TNF-α and IL-1β levels in pleural lavage (p < 0.001). In the CFA animal model, EEMA significantly reduced the nociceptive and hyperalgesic behaviors demonstrated by the rearing test (p < 0.01 or p < 0.05) and decreased mechanical hyperalgesia (p < 0.001). EEMA produced a significant improvement in mobility in the open-field test (only at the higher dose, p < 0.05). EEMA significantly (p < 0.01) increased hindpaw grip strength. The diameter of CFA-induced ipsilateral knee edema was significantly reduced (p < 0.001) by EEMA, which was related to reduced levels of IL-6 and TNF-α in the joint knee (p < 0.01). No indication of hepatic injury after chronic treatment was found.

CONCLUSION

Taken together, these results contribute to the chemical and pharmacological knowledge of M. albicans and demonstrated that this medicinal plant appears to be able to mitigate deleterious symptoms of RA, which supports its use in folk medicine.

Outcomes of immunomodulatory and biologic therapy in people living with HIV

OBJECTIVES

Immunomodulatory drugs (IMDs) are crucial for treating autoimmune, inflammatory, and oncologic conditions. Data regarding the safety of IMDs in people living with HIV (PLWH) are limited. We describe outcomes in all PLWH prescribed these agents from 2000--2019 at two academic medical centers.

DESIGN

Retrospective cohort study.

METHODS

We systematically identified and reviewed charts of all PLWH receiving IMDs. We defined a treatment episode as an uninterrupted period on an IMD regimen. We quantified infections, blips (detectable plasma HIV RNA following an undetectable result), and virologic failure (progression from plasma HIV RNA <200 copies/ml to two consecutive values >200 copies/ml despite ART).

RESULTS

Seventy-seven patients contributed 110 treatment episodes. Rheumatologic comorbidities were the most frequent indication. The most common IMD classes were TNF inhibitors, antimetabolites, and checkpoint inhibitors. Ninety percent of treatment episodes involved concomitant ART. Median pretreatment CD4 T-cell count was 609 cells/μl (IQR 375--861). Among 51 treatment episodes on ART with undetectable pretreatment plasma HIV RNA, HIV became detectable within 1 year in 21 of 51 cases (41.2%); there were no instances of virologic failure. Compared with other agents, treatment episodes involving checkpoint inhibitors were more likely to involve a blip (77.8 vs. 33.3%, P = 0.015). Thirteen treatment episodes (11.8%) were associated with concomitant infection; none was attributed to IMDs by the treating clinician.

CONCLUSION

PLWH treated with IMDs should be monitored carefully for virologic blips and incident infections. Checkpoint inhibitors may be associated with a higher rate of viral blips, although the clinical significance is unclear.

High dose trivalent influenza vaccine compared to standard dose vaccine in patients with rheumatoid arthritis receiving TNF-alpha inhibitor therapy and healthy controls: Results of the DMID 10-0076 randomized clinical trial

INTRODUCTION

Subjects with rheumatoid arthritis (RA) receiving tumor necrosis factor-inhibiting (TNFi) therapies are at risk for severe influenza, and may respond less well to influenza vaccine. We examined the safety and immunogenicity of high dose influenza vaccine (HD) compared to standard dose vaccine (SD) in participants with RA receiving stable TNFi.

METHODS

A randomized, double-blinded, Phase II study was conducted in adults with RA receiving TNFi, and healthy, gender and age-matched control subjects. Participants were immunized with HD (Sanofi Pasteur Fluzone High Dose [60 mcg × 3 strains]) or SD (Sanofi Pasteur Fluzone® [15 mcg × 3 strains]) intramuscularly (IM). A self-administered memory aid recorded temperature and systemic and local adverse events (AEs) for 8 days, and safety was evaluated and serum obtained to measure HAI activity on days 7, 21 and 180 days following vaccination.

RESULTS

A greater proportion of RA subjects who received HD seroconverted at day 21 compared to SD, although this was not statistically significant. GMT antibody responses in RA subjects who received HD compared to SD were greater for all strains on day 21, and this was significant for H1N1. Seroconversion rates and GMT values were not different between RA subjects and control subjects. There were no safety concerns for HD or SD in RA subjects, and RA-related symptoms did not differ between SD and HD recipients by a RA-symptom questionnaire (RAPID 3).

CONCLUSIONS

TNF-inhibitor therapy in people with RA did not appear to influence the immunogenicity of either SD or HD. Influenza seroconversion and GMT values were higher among RA subjects receiving HD compared to SD; however, differences were small and a larger study is needed to validate these findings. Given the apparent risk of increased influenza-related morbidity and mortality among immune compromised subjects, the higher GMT values generated by HD may be beneficial.

Window of opportunity in rheumatoid arthritis - definitions and supporting evidence: from old to new perspectives

The therapeutic window of opportunity in rheumatoid arthritis (RA) is often referred to. However, some have questioned whether such a period, in which the disease is more susceptible to disease-modifying treatment, really exists. Observational studies are most frequently referenced as supporting evidence, but results of such studies are subject to confounding. In addition formal consensus on the definition of the term has never been reached. We first reviewed the literature to establish if there is agreement on the concept of the window of opportunity in terms of its time period and the outcomes influenced. Second, a systemic literature search was performed on the evidence of the benefit of early versus delayed treatment as provided by randomised clinical trials. We observed that the concept of the window of opportunity has changed with respect to timing and outcome since its first description 25 years ago. There is an ‘old definition’ pointing to the first 2 years after diagnosis with increased potential for disease-modifying treatment to prevent severe radiographic damage and disability. Strong evidence supports this concept. A ‘new definition’ presumes a therapeutic window in a pre-RA phase in which the biologic processes could be halted and RA development prevented by very early treatment. This definition is not supported by evidence, although is less well studied in trials. Some suggestions for future research in this area are made.

Unchanging premature mortality trends in systemic lupus erythematosus: a general population-based study (1999-2014)

Objective

Patients with SLE have increased morbidity and premature mortality. Whether this mortality gap has improved in recent years, as in RA, is unknown.

Methods

We conducted a population-based cohort study using a medical records database representative of the general population of the UK. We identified incident SLE cases and matched non-SLE controls between 1999 and 2014, divided into two subgroups based on year of SLE diagnosis, forming the early cohort (1999-2006) and late cohort (2007-14). We compared the mortality rates and hazard ratios, adjusting for potential confounders.

Results

We identified 1470 and 1666 incident SLE cases in the early and late cohorts, respectively. In both cohorts, SLE patients had similar levels of excess mortality compared with their matched comparators [15.9 vs 7.9 deaths/1000 person-years (PY) in the early cohort and 13.8 vs 7.0 deaths/1000 PY in the late cohort]. The corresponding mortality hazard ratios were 2.15 (95% CI 1.63, 2.83) and 2.12 (95% CI 1.61, 2.80) in the early and late cohorts, respectively (P-value for interaction = 0.95). The absolute mortality differences were 8.0 (95% CI 4.3, 11.8) and 6.8 (95% CI 3.5, 10.0) deaths/1000 PY, respectively (P-value for interaction = 0.61).

Conclusion

This general population-based cohort study suggests that excess mortality has not improved among SLE patients in recent years, remaining greater than double that of comparators, unlike RA during the same period. This highlights a critical unmet need for the development of new therapeutic agents and improved management strategies for SLE and its comorbidities.

Immunotherapeutics in Pediatric Autoimmune Central Nervous System Disease: Agents and Mechanisms

Beyond the major advances produced by careful clinical-radiological phenotyping and biomarker development in autoimmune central nervous system disorders, a comprehensive knowledge of the range of available immune therapies and a deeper understanding of their action should benefit therapeutic decision-making. This review discusses the agents used in neuroimmunology and their mechanisms of action. First-line treatments typically include corticosteroids, intravenous immunoglobulin, and plasmapheresis, while for severe disease second-line "induction" agents such as rituximab or cyclophosphamide are used. Steroid-sparing agents such as mycophenolate, azathioprine, or methotrexate are often used in potentially relapsing or corticosteroid-dependent diseases. Lessons from adult neuroimmunology and rheumatology could be translated into pediatric autoimmune central nervous system disease in the future, including the potential utility of monoclonal antibodies targeting lymphocytes, adhesion molecules for lymphocytic migration, cytokines or their receptors, or complement. Finally, many agents used in other fields have multiple mechanisms of action, including immunomodulation, with potential usefulness in neuroimmunology, such as antibiotics, psychotropic drugs, probiotics, gut health, and ketogenic diet. All currently accepted and future potential agents have adverse effects, which can be severe; therefore, a "risk-versus-benefit" determination should guide therapeutic decision-making.

Benralizumab for patients with mild to moderate, persistent asthma (BISE): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

Benralizumab is a humanised, anti-interleukin 5 receptor α monoclonal antibody that directly and rapidly depletes eosinophils, reduces asthma exacerbations, and improves lung function for patients with severe eosinophilic asthma. The objective of this trial was to assess the safety and efficacy of benralizumab for patients with mild to moderate, persistent asthma.

METHODS

In this randomised, double-blind, placebo-controlled, phase 3 trial, we recruited patients aged 18-75 years, weighing at least 40 kg, and with a postbronchodilator reversibility in forced expiratory volume in 1 s (FEV₁) of at least 12% at screening, from 52 clinical research centres in six countries. Patients must have been receiving either low- to medium-dosage inhaled corticosteroids (ICS) or low-dosage ICS plus long-acting β₂ agonist fixed-combination therapy at screening, had a morning prebronchodilator FEV₁ of more than 50% to 90% predicted at screening, and had one or more of the following symptoms within the 7 days before randomisation: a daytime or night-time asthma symptom score of at least 1 for at least 2 days, rescue short-acting β₂ agonist use for at least 2 days, or night-time awakenings due to asthma for at least one night. We converted patients' ICS treatments to 180 μg or 200 μg budesonide dry powder inhaler twice daily for the entire duration of the study using the approved dosages in the patients' respective countries and randomly allocated them (1:1; stratified by blood eosinophil count [<300 cells per μL vs ≥300 cells per μL] and region [USA vs the rest of the world]) with an interactive web-based voice response system to receive subcutaneous placebo or benralizumab 30 mg injections every 4 weeks for 12 weeks. All patients and investigators involved in patient treatment or clinical assessment and those assessing outcomes were masked to treatment allocation. The primary endpoint was change from baseline prebronchodilator FEV₁ at week 12. Efficacy analyses used an intention to treat approach. This trial is registered with ClinicalTrials.gov, number NCT02322775.

FINDINGS

Between Feb 2, 2015, and April 24, 2015, we enrolled 351 patients, with 211 (60%) randomly assigned (105 [50%] to placebo and 106 [50%] to benralizumab). Benralizumab resulted in an 80 mL (95% CI 0-150; p=0·04) greater improvement (least-squares mean difference) in prebronchodilator FEV₁ after 12 weeks than did placebo (placebo group: 2246 mL [SD 768] at baseline vs 2261 mL [796] at week 12, change from baseline of 0 mL; benralizumab group: 2248 mL [606] vs 2310 mL [670], 70 mL). 44 (42%) patients in the benralizumab group had adverse events compared with 49 (47%) in the placebo group. The most common adverse events for both groups were nasopharyngitis (eight [8%] patients in each group) and upper respiratory tract infections (five [5%] patients in each group). Serious adverse events occurred in two (2%) patients each in the benralizumab (pancytopenia and a suicide attempt, both considered unrelated to treatment) and placebo (cervix carcinoma and colon adenoma) groups.

INTERPRETATION

This study suggests that active and modifiable disease processes might be ongoing in patients with mild to moderate, persistent asthma receiving ICS. Although the lung function improvement observed does not warrant use of benralizumab in this population because it did not reach the minimum clinically important difference of 10%, further studies to assess this finding should be considered.

FUNDING

AstraZeneca.

Demystifying the cytokine network: Mathematical models point the way

Cytokines provide the means by which immune cells communicate with each other and with parenchymal cells. There are over one hundred cytokines and many exist in families that share receptor components and signal transduction pathways, creating complex networks. Reductionist approaches to understanding the role of specific cytokines, through the use of gene-targeted mice, have revealed further complexity in the form of redundancy and pleiotropy in cytokine function. Creating an understanding of the complex interactions between cytokines and their target cells is challenging experimentally. Mathematical and computational modeling provides a robust set of tools by which complex interactions between cytokines can be studied and analyzed, in the process creating novel insights that can be further tested experimentally. This review will discuss and provide examples of the different modeling approaches that have been used to increase our understanding of cytokine networks. This includes discussion of knowledge-based and data-driven modeling approaches and the recent advance in single-cell analysis. The use of modeling to optimize cytokine-based therapies will also be discussed.

Combining antigen and immunomodulators: Emerging trends in antigen-specific immunotherapy for autoimmunity

A majority of current therapies for autoimmune diseases are general immunosuppressants, which can compromise patient response to opportunistic infection and lead to adverse events. Using antigen-specific immunotherapy (ASIT) to selectively disarm autoimmune diseases, without suppressing the global immune response, would be a transformative therapy for patients. ASIT has been used historically in allergy hyposensitization therapy to induce tolerance to an allergen. Similar strategies to induce immune tolerance toward autoantigens responsible for autoimmune disease have been attempted but have yielded limited clinical success. Recent studies of ASIT for autoimmunity have explored combination therapy, combining the disease-causing autoantigen with an immunomodulatory compound. ASIT combination therapy may direct the immune response in an antigen-specific manner, potentially reversing the root cause of autoimmunity while limiting side effects. This review analyzes recent advances in ASIT applied to autoimmune diseases, emphasizing current combination therapies and future strategies.