Drug Tolerant Anti-drug Antibody Assay for Infliximab Treatment in Clinical Practice Identifies Positive Cases Earlier

Screening and experimental validation of diagnostic gene in ulcerative colitis with anti-TNF-α therapy

In clinical practice, the diagnosis of ulcerative colitis (UC) mainly relies on a comprehensive analysis of a series of signs and symptoms of patients. The current biomarkers for diagnosis of UC and prognostic prediction of anti-TNF-α therapy are inaccurate. The present study aimed to perform an integrative analysis of gene expression profiles in patients with UC. A total of seven datasets from the GEO database that met our strict inclusion criteria were included. After identifying differentially expressed genes (DEGs) between UC patients and healthy individuals, the diagnostic and prognostic utility of the DEGs were then analyzed via least absolute shrinkage and selection operator and support-vector machine recursive feature elimination. Subgroup analyses of the treated and untreated groups, as well as the treatment-response group and non-response group, were also performed. Furthermore, the relationship between the expressions of UC-related genes and infiltration of immune cells in the course of treatment was also investigated. Immunohistochemical (IHC) assay was used to verify the gene expression in inflamed UC tissues. When considering all the applied methods, DUOX2, PI3, S100P, MMP7, and S100A8 had priority to be defined as the characteristic genes among DEGs. The area under curve (AUC) of the five genes, which were all consistently over-expressed, based on an external validation dataset, were all above 0.94 for UC diagnosis. Four of the five genes (DUOX2, PI3, MMP7, and S100A8) were down-regulated between treatment-responsive and nonresponsive patients. A significant difference was also observed concerning the infiltration of immune cells, including macrophage and neutrophil, between the two groups (treatment responsive and nonresponsive). The changes in the expression of DUOX2 and MMP7 based on the IHC assay were highly consistent with the results obtained in the current study. This confirmed the mild to moderate diagnostic and predictive value of DUOX2 and MMP7 in patients with UC. The conducted analyses showed that the expression profile of the five identified biomarkers accurately detects UC, whereas four of the five genes evidently predicted the response to anti-TNF-α therapy.

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.

Optimization of a Quantitative Anti-Drug Antibodies against Infliximab Assay with the Liquid Chromatography-Tandem Mass Spectrometry: A Method Validation Study and Future Perspectives

Monoclonal antibodies (mAbs), such as infliximab, are important treatment options for different diseases. Immunogenicity is a major risk, resulting in anti-drug antibodies (ADAs), being associated with adverse events and loss of response, influencing long-term outcomes. The development of ADAs against infliximab is primarily measured by immunoassays like radioimmunoassay (RIA). Although liquid chromatography-tandem mass spectrometry (LC-MS/MS) is increasingly utilized across different fields, this technique is currently not used for ADAs against infliximab measurements. Therefore, we developed the first LC-MS/MS method. Stable isotopically labeled infliximab antigen-binding fragments (SIL IFX F(ab')₂) were used to bind and measure ADAs indirectly. Protein A magnetic beads were used to capture IgG, including ADAs, whereafter SIL IFX F(ab')₂ was added for labeling. After washing, internal standard addition, elution, denaturation and digestion samples were measured by LC-MS/MS. Internal validation showed good linearity between 0.1 and 16 mg/L (R² > 0.998). Sixty samples were used for cross-validation with RIA, and no significant difference between ADA concentrations was found. The methods had high correlation (R = 0.94, p < 0.001) and excellent agreement, intraclass correlation coefficient = 0.912 (95% confidence interval 0.858-0.947, p < 0.001). We present the first ADA against the infliximab LC-MS/MS method. The method is amendable for quantifying other ADAs, making it applicable as a template for future ADA methods.

Free antibodies-to-infliximab are biomarker for predicting the effect of dose intensification in pediatric Crohn's disease patients with secondary loss of response

Background

Immunogenicity to antitumor necrosis factor alpha agents, such as infliximab (IFX), may lead to therapeutic failure.

Objectives

This study evaluated the relationship between free and total antibodies-to-infliximab (ATIs), trough levels (TLs) of IFX, and the response to dose intensification.

Design

We performed a prospective, observational study including pediatric patients with Crohn's disease (CD) receiving IFX maintenance therapy without dose intensification.

Methods

We compared clinical and laboratory outcomes according to the presence of free and total ATIs. Factors associated with response to IFX dose intensification were investigated by analyzing IFX TLs and free and total ATIs.

Results

Of the 98 patients, 9 patients had detectable free ATIs and 38 patients had total ATIs. Patients with free ATIs had significantly lower TLs (0.7 versus 5.1 µg/mL, p < 0.001) than patients without free ATIs. However, there was no difference in the IFX TLs according to the presence of total ATIs (p = 0.2523). Analysis of the 38 samples with total ATIs showed that response to dose intensification was significantly lower in patients with free ATIs than those without free ATIs (22.2% versus 65.5%, p < 0.001). In addition, free ATIs were the only factor with poor response to dose intensification [odds ratio (OR): 14.15, 95% confidence interval (CI): 1.31-151.97, p = 0.0140]. According to the receiver operating characteristic analysis, the optimal cutoff level indicating non-response to IFX dose intensification was 30.0 AU/mL for free ATIs concentration (area under curve, 0.792; 95% CI: 0.590-0.942; sensitivity, 60.0%; specificity, 96.7%; p = 0.0241).

Conclusion

Free ATIs, but not total ATIs, have a negative impact on the course of CD. Free ATIs are potential reliable biomarker for predicting the effect of dose intensification in patients with loss of response to IFX. Future studies based on serial and proactive therapeutic drug monitoring are required in the future.

Recent Advances in the Optimization of Anti-TNF Treatment in Patients with Inflammatory Bowel Disease

Despite the evolution in inflammatory bowel disease (IBD) management during the last 20 years owing to the advent of new advanced therapies, anti-TNF agents still remain the cornerstone of therapy for both Crohn's disease and ulcerative colitis. However, this does not only secure favorable outcomes for patients considering the progressive disease character and the high likelihood of primary or secondary loss of response. Therefore, trying to reach a better treatment approach and maximize the benefits anti-TNF agents offer, optimization strategies should be examined. It has been indicated that optimizing treatment with anti-TNF enhances drug efficacy and has been associated with improved disease outcomes and a complication-free disease course. From this perspective, we aim to provide an overview of currently available data and recent advances in the practices of anti-TNF treatment optimization. Special focus has been given to the role of therapeutic drug monitoring (TDM), as well as the utility of combining anti-TNF with an immunomodulator and the treat-to-target approach.

Therapeutic Drug Monitoring in Practice for Inflammatory Bowel Disease

PURPOSE OF REVIEW

To outline the development, rationale, and practical use of therapeutic drug monitoring in patients with inflammatory bowel disease.

RECENT FINDINGS

Therapeutic drug monitoring is traditionally discussed in terms of a proactive or reactive approach. However, these terms are not always consistently defined and can be confusing when translating research to clinical practice. Personalized approaches incorporating clinical context and precision medicine are emerging. Personalized therapeutic drug monitoring combines a structured and proactive strategy for monitoring biologic concentrations as well as identification of antidrug antibody development or subtherapeutic dosing in the setting of loss of response. Optimizing biologic therapy can improve outcomes and avoid loss of response. Why, when, and how we measure drug troughs and anti-drug antibodies is a moving target, though what is known is that the appropriate and evidence-based use of this practice prevents adverse events and improves outcomes in patients with inflammatory bowel disease.

Assessing Immunogenicity of Biologic Drugs in Inflammatory Joint Diseases: Progress Towards Personalized Medicine

Biologic drugs have greatly improved treatment outcomes of inflammatory joint diseases, but a substantial proportion of patients either do not respond to treatment or lose response over time. Drug immunogenicity, manifested as the formation of anti-drug antibodies (ADAb), constitute a significant clinical problem. Anti-drug antibodies influence the pharmacokinetics of the drug, are associated with reduced clinical efficacy, and an increased risk of adverse events such as infusion reactions. The prevalence of ADAb differs among drugs and diseases, and the detection of ADAb also depends on the assay format. Most data exist for the tumor necrosis factor-alpha inhibitors infliximab and adalimumab, with a frequency of ADAb that ranges from 10 to 60% across studies. Measurement of ADAb and serum drug concentrations, therapeutic drug monitoring, has been suggested as a strategy to optimize therapy with biologic drugs. Although the recent randomized clinical Norwegian Drug Monitoring (NOR-DRUM) trials show promise towards a personalized medicine prescribing approach by therapeutic drug monitoring, several challenges remain. A plethora of assay formats, with widely differing properties, is currently used for measuring ADAb. Comparing results between different assays and laboratories is difficult, which complicates the development of cut-offs necessary for guidelines and the implementation of ADAb measurements in clinical practice. With the possible exception of infliximab, limited data on clinical relevance and cost effectiveness exist to support therapeutic drug monitoring as a routine clinical strategy to monitor biologic drugs in inflammatory joint diseases. The aim of this review is to provide an overview of the characteristics and prevalence of ADAb, predisposing factors to ADAb formation, commonly used assessment methods, clinical consequences of ADAb, and the potential implications of ADAb assessments for everyday treatment of inflammatory joint diseases.

A Systematic Review on the interest of Drug Tolerant assay in the monitoring of Inflammatory Bowel Disease

Many patients with inflammatory bowel disease (IBD) are treated with anti-tumor necrosis factor (TNF) therapies, of which infliximab (IFX) is most commonly used. Loss of response (LOR) to anti-TNF therapy due to immunogenic failure accounts for 20% of subsequent medical intervention and is defined, using a drug sensitive assay, as low or undetectable concentration of drug with high titers of anti-drug antibodies (ADAb). We performed a systematic review to investigate the use of a drug tolerant assay during both induction and maintenance to monitor patients treated with anti-TNFs. After the search on PubMed, 90 publications were reviewed. Most ADAb detection methods are drug sensitive, cannot detect ADAb in the presence of drug, and therefore cannot be used close to drug administration, when the drug concentration is too high. To overcome this major limitation, several drug-tolerant techniques have been developed and will be discussed in this review. Using drug-tolerant assays ADAb against infliximab (IFX) or adalimumab (ADM) can be detected during induction and predict primary non-response or LOR. Drug sensitive assays do not allow detection of ADAb during the induction phase as IFX or ADM concentration is typically high.

The Long-Term Clinical Effectiveness of Ustekinumab in Antitumor Necrosis Factor-Experienced Crohn’s Disease Patients

Background

Crohn’s disease (CD) is a chronic inflammatory bowel disease (IBD) of unknown etiology. Ustekinumab (UST), an interleukin (IL)-12 and IL-23 antibody, has been approved in the recent years to treat IBD, both Crohn’s disease and ulcerative colitis. This study clarifies the long-term effectiveness of ustekinumab (UST) in antitumor necrosis factor (anti-TNF) refractory Crohn’s disease in Middle Eastern patients.

Methods

A retrospective review study, including 30 refractory or medication-intolerant patients with Crohn’s disease, was conducted at a tertiary care center in Riyadh, Saudi Arabia. The patients were started on ustekinumab and followed up for at least 52 weeks. Follow-up was performed on weeks 12, 24, and 52. Data related to demographic and laboratory parameters, the dosing schedule of ustekinumab administration, and the Harvey-Bradshaw index (HBI) were collected. Clinical remission and response rates were assessed. Statistical analysis was performed using SPSS Statistics version 28.0 (IBM Corp., Armonk, NY, USA). A statistical significance threshold of p < 0.05 was adopted.

Results

The mean age of the study subjects was 34.2 ± 17.9 years (95% confidence interval (CI): 27.5-40.9), with a mean disease duration of 10.6 ± 4.9 years (95% CI: 8.8-12.5). Of our cohort, 56.7% failed two biologics during their disease course, and about 20% failed three different biologics. The percentage of patients who used thiopurines was 76.7%, while 6.7% used methotrexate. Concurrent immunomodulators were used by 58.6% of the patients. Corticosteroids were given to 13.3% of the patients. Intravenous induction of UST at 6 mg/kg was used for 90% of the patients, while only 10% used a 260 mg subcutaneous dose. At week 12, 73.3% of the patients had a clinical response, and 66.7% achieved clinical remission. Corticosteroid-free remission, clinical response, and clinical remission showed a decreasing percentage trend between weeks 12 and 24 compared to week 52 where a spike was observed in all aforementioned parameters. The clinical response rate at week 52 was 76.7%. The p-values from cross-tabulation were significant for clinical response and remission when comparing week 12 to weeks 24 and 52.

Conclusion

Ustekinumab presents a safe and effective treatment option in moderate to severe Crohn’s disease patients with previous exposure to multiple biologics.

Could Mucosal TNF Transcript as a Biomarker Candidate Help Optimize Anti-TNF Biological Therapy in Patients With Ulcerative Colitis?

Anti-tumor necrosis factor (TNF) biological therapy has generally been accepted as a standard therapeutic option in inflammatory bowel disease (IBD) patient who are refractory to steroids or immunomodulators. However, the primary and secondary nonresponse rates to anti-TNF bioagents in patients with IBD are high. To improve the response rate, anti-TNF bioagents must be offered to the appropriate IBD patients, and the withdrawal of anti-TNF bioagents needs to be done at the right time. In this context, reliable and reproducible biomarkers can provide important supportive information for clinicians to make correct decisions based on the patient’s individual situation. In this review, we summarized the current understanding of using mucosal TNF transcript (TNF) to improve the precision of anti-TNF biological therapy strategies in patients with ulcerative colitis (UC). Analysis of published literature showed that mucosal TNF could affect the precision of the early identification of candidates who will benefit from anti-TNF therapy prior to treatment, the assessment of response and mucosal healing, and the prediction of discontinuation of anti-TNF biological therapy and relapse after drug withdrawal. Challenges and limitations of using mucosal TNF as a biomarker in applying individualized anti-TNF biological therapy in patients with UC still remain and need to be further investigated.

Low immunogenicity of vedolizumab determined by a simple drug-tolerant assay in patients with ulcerative colitis

Vedolizumab is a humanized monoclonal antibody against the α4β7 integrin and is approved for treatment of inflammatory bowel diseases. In this study, we evaluated the immunogenicity of vedolizumab using a simple drug-tolerant assay developed in our laboratory. Serum vedolizumab trough levels and anti-vedolizumab antibody (AVA) levels were measured using new immunoassays in 37 patients with ulcerative colitis (UC) under vedolizumab maintenance therapy. The median vedolizumab trough level at week 30 was 16.0 μg/ml (interquartile range, 7.3–24.4). The vedolizumab trough level of the patients with clinical remission (partial Mayo score ≤1) was significantly higher than that of clinically active patients (16.7 μg/ml vs 6.8). The cut-off value of vedolizumab level predicting clinical remission at week 30 was 7.34 μg/ml. The median AVA level of patients under vedolizumab maintenance therapy was similar to that of healthy controls (n = 20) (0.032 μg/ml-c vs 0.022). One of 37 patients (2.7%) was judged to be AVA positive. There was no significant difference in serum AVA and vedolizumab trough levels between biologics-naïve (n = 19) and biologics-switched (prior anti-TNFα-exposed) patients (n = 18). In conclusion, the simple drug-tolerant assay developed in our laboratory demonstrated low immuno­genicity of vedolizumab. Prior use of anti-TNFα drugs did not affect the immunogenicity of vedolizumab.

Evaluation of anti-TNF therapeutic response in patients with inflammatory bowel disease: Current and novel biomarkers

Neutralizing tumour necrosis factor (TNF) antibodies have been widely used to treat inflammatory bowel disease (IBD) in the clinical practice. In this review, the principal biomarker analysis revealed that faecal calprotectin, C-reactive protein, serum or mucosal concentrations of anti-TNF monoclonal antibodies (mAbs) and antibodies to anti-TNF mAbs are commonly used as current biomarkers in the evaluation of anti-TNF therapeutic efficacy. However, mucosal cytokine transcripts. microRNAs, proteomics and faecal and mucosal gut microbiota profile and mucosal histological features are reported to be novel candidates of biomarkers with high clinical utility in the evaluation of anti-TNF therapeutic efficacy in patients with IBD. Therefore, a robust validation of novel promising biomarkers and comparison studies between current used and novel biomarkers are urgently required to improve their value in the evaluation of therapeutic efficacy and optimization of personalized medicine and identification of IBD candidates for anti-TNF therapy in future clinical practice.