Comparison of Timing to Develop Anti-Drug Antibodies to Infliximab and Adalimumab Between Adult and Pediatric Age Groups, Males and Females

Uncovering the interleukin-12 pharmacokinetic desensitization mechanism and its consequences with mathematical modeling

The cytokine interleukin-12 (IL-12) is a potential immunotherapy because of its ability to induce a Th1 immune response. However, success in the clinic has been limited due to a phenomenon called IL-12 desensitization - the trend where repeated exposure to IL-12 leads to reduced IL-12 concentrations (pharmacokinetics) and biological effects (pharmacodynamics). Here, we investigated IL-12 pharmacokinetic desensitization via a modeling approach to (i) validate proposed mechanisms in literature and (ii) develop a mathematical model capable of predicting IL-12 pharmacokinetic desensitization. Two potential causes of IL-12 pharmacokinetic desensitization were identified: increased clearance or reduced bioavailability of IL-12 following repeated doses. Increased IL-12 clearance was previously proposed to occur due to the upregulation of IL-12 receptor on T cells that causes increased receptor-mediated clearance in the serum. However, our model with this mechanism, the accelerated-clearance model, failed to capture trends in clinical trial data. Alternatively, our novel reduced-bioavailability model assumed that upregulation of IL-12 receptor on T cells in the lymphatic system leads to IL-12 sequestration, inhibiting the transport to the blood. This model accurately fits IL-12 pharmacokinetic data from three clinical trials, supporting its biological relevance. Using this model, we analyzed the model parameter space to illustrate that IL-12 desensitization occurs over a robust range of parameter values and to identify the conditions required for desensitization. We next simulated local, continuous IL-12 delivery and identified several methods to mitigate systemic IL-12 exposure. Ultimately, our results provide quantitative validation of our proposed mechanism and allow for accurate prediction of IL-12 pharmacokinetics over repeated doses.

Early Anti-Drug Antibodies Predict Adalimumab Response in Juvenile Idiopathic Arthritis

Adalimumab, a TNF-alpha inhibitor, is approved to treat juvenile idiopathic arthritis (JIA), helping control disease activity and reduce flare frequency. This study aims to investigate predictors of treatment response, including anti-drug antibodies. We reviewed 65 JIA patients (mean age 10.47 ± 3.90 years; 61.5% male) receiving adalimumab for an average of 2.64 ± 0.56 years, with demographics, laboratory parameters, therapeutic regimens, and treatment outcomes recorded. Disease status was evaluated using the Wallace criteria up to 36 months post-treatment initiation, and anti-adalimumab antibody levels were measured after 6 months of treatment. Enthesitis-related arthritis was the most common subtype (64.6%). Inactive disease status was achieved by 83.1% of patients, with 59.3% experiencing relapse. Detectable anti-adalimumab antibody at six months (p = 0.023) and temporomandibular joint (TMJ) involvement (p = 0.038) identified those less likely to achieve inactive disease. An antibody level cutoff of 7.426 ng/mL best predicted response (AUC = 0.808; p = 0.008), while high anti-adalimumab antibody levels after treatment (p = 0.032) and an injection intervals over two weeks (p = 0.042) were predictors of future flares. Our results highlight that the presence of anti-adalimumab antibodies six months after treatment is a risk factor for poor response to adalimumab therapy.

Detection of antibodies to infliximab in routine care: a 4-year French retrospective study

Despite its wide use to treat various inflammatory diseases, infliximab becomes ineffective in some patients due to inadequate drug levels and production of anti-drug antibodies (ADA). The aim of this study was to compare the prevalence and ADA levels in a large cohort of patients. ADA and infliximab (IFX) through levels measured by enzyme-linked immunosorbent assay were collected from 505 patients within a period of 4 years. The results indicate that (i) 13.5% of patients produce ADA, (ii) male patients were more likely to produce ADA at levels above 10 000 ng/ml than female patients, (iii) ADA levels were lower when associated with immunosuppressant drugs, (iv) there was an inverse relationship between ADA presence and IFX detection, and (v) no correlation was observed between ADA levels and number of injections or brand of IFX administered. This study improves our understanding of the factors promoting IFX immunogenicity and highlights the need to develop personalized treatment strategies.

Immunogenicity of Adalimumab in Patients with Non-Infectious Uveitis: Systematic Review and Meta-Analysis

OBJECTIVE

To review the prevalence, incidence, and risk factors for developing anti-drug antibodies (AAA) in patients with non-infectious uveitis (NIU) treated with Adalimumab (ADA).

METHODS

A systematic literature search was performed on PubMed, EMBASE, Virtual Health Library, Cochrane, and medRxiv. Meta-analysis was performed using random effects.

RESULTS

Nine out of 2,373 studies were included. The prevalence of AAA in NIU patients treated with ADA was 9% (95% CI: 2% to 37%, I2 = 95% with a P<0.01), it was significantly higher in real-life scenarios (observational studies) than in clinical trials. The pooled incidence at 12 months was 27% (CI 95% 16%-42% I2 = 0%). Several factors have been associated with AAA generation in NIU patients, including the non-use of concomitant immunosuppressants, presence of autoimmune systemic disease, female gender, etc.

CONCLUSION

This study showed that AAA prevalence is higher in real-life scenarios compared to clinical trials. Further research is needed to elucidate the factors that trigger AAA generation in NIU patients.

Infliximab therapy decreases the expression of serum and faecal miR-126 and miR-20a in paediatric Crohn's disease: A pilot study

AIM

We aimed to evaluate the serum and faecal expression of miR-126 and miR-20a in children with Crohn's disease (CD) during infliximab (IFX) therapy.

METHODS

In this prospective observational study, serum and faeces from CD patients were collected before IFX therapy (T0), after induction (T1) and after 6 months from IFX (T2). IFX levels were determined by Enzyme-linked immunosorbent assay at T1 and T2. miRNAs were profiled through Real-Time RT-PCR. The activity of disease was evaluated through the Paediatric Crohn's disease activity index (PCDAI), serum C-reactive protein (CRP) and faecal calprotectin.

RESULTS

Nine CD children were enrolled. Serum and faecal miR-126 and miR-20a levels were higher at T0 and showed a time-dependent decrease, being significantly down-regulated after IFX treatment at T2. Specifically, IFX levels recorded at T1 and T2 negatively correlated with the serum and faecal expression of miR-126 and miR-20a. Serum and faecal changes of miR-126 and miR20-a were positively associated with the decrease of the inflammatory marker CRP and PDCAI at all time points.

CONCLUSION

In children with CD, IFX therapy decreases the expression of serum and faecal miR-126 and miR-20a, suggesting an involvement of these two miRNAs in the action of the drug.

Serum cytokines MCP-1 and GCS-F as potential biomarkers in pediatric inflammatory bowel disease

BACKGROUND

Inflammatory bowel diseases (IBDs) with the subtypes ulcerative colitis (UC) and Crohn disease (CD), are chronic autoimmune inflammatory disorders of the gastrointestinal tract. Cytokines are associated with the development and progression in pediatric IBD. We measured cytokine levels in pediatric IBD patients to assess their potential function as biomarkers in disease assessment.

METHOD

In this prospective cohort study, we enrolled 33 children with IBD. All patients were in stable remission for 3 months on enrollment. Patients who developed a relapse within six months after enrollment were classified as relapsers. Blood sampling was performed at enrolment and for relapsers in relapse and post-relapse. Serum concentrations of 14 cytokines, chemokines and growth factors (IL-1α, IL-1β, IL-6, IL-12p40, IP-10, TNF-α, IFN-γ, IL-10, IL-8, MIP-1α, MCP-1, MCP-3, G-CSF, GM-CSF) were measured simultaneously using multiplex bead-based sandwich immunoassay on Luminex 100 system.

RESULTS

MCP-1 was significantly higher in CD patients compared to UC patients at each disease stage: stable remission (P<0.048), unstable remission (P<0.013), relapse (P<0.026) and post-relapse (P<0.024). G-CSF was significantly increased in UC patients developing a relapse and in post-relapse stage compared to UC patients in remission (P<0.02 and p<0.03, respectively).

CONCLUSION

MCP-1 showed potential as a diagnostic biomarker in CD patients independent of disease activity as it was able to discriminate between subtypes of pediatric IBD. In UC patients, G-CSF was significantly elevated in relapsers indicating its use and role as a potential prognostic biomarker.

Drug-survival profiling of second-line biologic therapy in rheumatoid arthritis: Choice of another tumour necrosis factor inhibitor or a biologic of different mode of action?

OBJECTIVES

To assess the best choice of second-line therapy between tumour necrosis factor-inhibitor (TNFi) and biologics of different-mode-of-action (BDMA-rituximab/tocilizumab/abatacept) in rheumatoid arthritis (RA) by evaluating drug-survival following discontinuation of the first-line TNFi.

METHODS

This retrospective drug-survival study was performed across two different hospitals by conventional-statistics and machine-learning approach.

RESULTS

From a total of 435 patients, 213 (48.9%; TNFi = 122, BDMA = 91) discontinued their second-line biologic {median drug-survival: TNFi, 27 months [95% confidence interval (95%CI) 22-32] vs BDMA, 37 months (95%CI 32-52)}. As a second-line biologic, BDMA was likely to reduce the risk of treatment-discontinuation [hazard-ratio (HR) 0.63, 95%CI 0.48-0.83] compared to TNFi, but only in seropositive-patients (HR 0.52, 95%CI 0.38-0.73), not in seronegative-RA. Drug-survival benefit of BDMA over TNFi was not observed if the seropositive-patients were previously exposed to monoclonal-TNFi (HR 0.77, 95%CI 0.49-1.22) versus soluble-TNFi (etanercept/biosimilars) or if the first-line TNFi was terminated within 23.9 months of initiation (HR 0.97, 95%CI 0.56-1.68).

CONCLUSIONS

BDMA, as a second-line biologic, is more likely to be sustained in seropositive-patients, particularly without prior exposure to monoclonal-TNFi. The drug-survival benefit of BDMA was not observed in seronegative-patients or if the first-line TNFi was stopped within 2 years.

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.

Cytokine Profile at Diagnosis Affecting Trough Concentration of Infliximab in Pediatric Crohn’s Disease

Background: This study aims to measure the concentration of cytokines produced during the inflammation process to investigate if there are any differences in response to treatment of pediatric Crohn’s disease and to determine if the initial tumor necrosis factor-alpha (TNF-α) level affected the trough concentration of infliximab (IFX). Methods: This study included 30 pediatric patients with moderate-to-severe Crohn’s disease. At the time of diagnosis, blood samples were collected for the measurement of cytokines (IL-6, TNF-α, IL-17A, and IL-10). Blood samples were extracted from patients who had begun IFX treatment to measure the IFX trough concentration immediately before the fourth dose administration. Results: All cytokines (TNF-α, IL-6, IL-10, and IL-17A) were significantly higher in patients who did not achieve clinical or biochemical remission than in those who did (p = 0.027, 0.006, 0.017, 0.032, respectively). TNF-α had a negative correlation with the IFX trough concentration (Pearson coefficient = −0.425, p = 0.034). The diagnostic capability of the initial TNF-α concentration to predict under the therapeutic IFX trough concentration, defined as less than 3 µg/mL, had an area under the receiver operating characteristic of 0.730 (p = 0.049). The TNF-α concentration was set at 27.6 pg/mL as the cutoff value. Conclusions: Measuring cytokines at the time of diagnosis can be used to predict the treatment response. Measuring the initial TNF-α concentration may help to predict the treatment response to IFX. When the initial TNF-α concentration is greater than 27.6 pg/mL, a higher dose of IFX may be more appropriate than routinely administering 5 mg/kg of IFX to maintain the therapeutic concentration.