Test accuracy of drug and antibody assays for predicting response to antitumour necrosis factor treatment in Crohn's disease: a systematic review and meta-analysis

Therapeutic effects of biological treatments on AA amyloidosis associated with inflammatory bowel disease: a case report and literature review

AA amyloidosis is a rare and significant complication of long-term inflammation that can be caused by a variety of disorders, including inflammatory bowel disease, and is linked to an increased risk of morbidity and mortality. To date, there has been no effective direct treatment, and treatment aims at treating the underlying condition with potent immunosuppression to limit inflammatory activity and, as a result, switch off amyloidogenesis. Theoretically, biological treatment can control AA amyloidosis by inducing and maintaining inflammatory bowel disease remission and inhibiting the synthesis of Serum Amyloid A, which is an acute phase reactant and precursor protein of AA amyloidosis that accumulates in the organs. We report the first case of ustekinumab's therapeutic effect after infliximab's loss of response in AA amyloidosis associated with Crohn's disease. We also conducted a literature review of the therapeutic effect of biological treatment on AA amyloidosis.

Non-Trough adalimumab and certolizumab drug levels associated with a therapeutic EULAR response in adherent patients with rheumatoid arthritis

OBJECTIVES

Interventions aimed at increasing tumour-necrosis factor-alpha inhibitor serum drug levels (SDLs) may improve treatment response; however, previous studies suggesting SDL cut-offs have not accounted for treatment adherence. The aim of this study was to establish the relationship between Adalimumab/Certolizumab SDLs and EULAR good vs non/moderate response, and to define SDL cut-offs associated with good response in fully adherent patients.

METHODS

In a prospective observational study, 475 patients with RA were treated with Certolizumab (n = 192) or Adalimumab (n = 283). At baseline, 3/6/12-months patients had DAS28, self-reported treatment adherence, and SDLs measured. Fully adherent patients were analysed as a subgroup. Follow-up data at 3/6/12-months was analysed separately. Median SDLs were compared in good vs non/moderate response, and receiver-operator characteristics curves (ROC) were used to establish cut-off SDLs.

RESULTS

Fully adherent good responders had significantly higher median Adalimumab/Certolizumab SDLs compared with non/moderate responders (p= 0·04 and p= 0·0005, respectively). ROC analysis reported 3-month non-trough Adalimumab SDLs discriminated good vs non/moderate response with an AUC of 0·63 (95% CI 0·52-0·75), with a cut-off of 7·5mg/l being 39·1% specific, and 80·9% sensitive. Similarly, 3-month non-trough Certolizumab SDLs discriminated good vs non/moderate response with an AUC of 0·65 (95% CI 0·51-0·78), with a cut-off of 26·0mg/l being 43·9% specific, and 77·8% sensitive.

CONCLUSION

In fully adherent patients, higher SDLs are detected in good responders suggesting that interventions to improve SDLs such as encouraging adherence could improve treatment response. 3-month non-trough SDL cut-offs of 7·5mg/l for Adalimumab and 26·0mg/l for Certolizumab may be useful in clinical practice.

Anti-infliximab antibodies and clinical response in noninfectious uveitis and scleritis patients treated with infliximab: A retrospective review

Purpose

To investigate the clinical response to infliximab in ocular inflammation patients who develop anti-infliximab antibodies (AIA) vs. those patients who do not develop AIA.

Observations

A retrospective review was performed of patients treated with infliximab for noninfectious uveitis (NIU) or scleritis. Clinical response was determined as a composite clinical endpoint and classified as complete, partial, or absent. Nine of 32 infliximab-treated patients (28%) were found to develop AIA. Among the AIA-positive patients, clinical response was complete in 7 patients (78%) and partial in 2 patients (22%). Among the AIA-negative patients, clinical response was complete in 15 patients (65%), partial in 6 patients (26%) and absent in 2 patients (9%). Serum infliximab levels tended to decrease with appearance of AIA but rarely became undetectable.

Conclusions and Importance

In this pilot study, AIA-positive patients did not have diminished clinical response to infliximab when compared with AIA-negative patients. There was a high rate of complete clinical response to infliximab in this group of NIU and scleritis patients. Approximately a quarter of patients developed AIA. AIA-positive patients did not have diminished rates of clinical response when compared with AIA-negative patients. This suggests that routine AIA monitoring may not be clinically useful, although validation of this finding in larger cohorts is necessary.

Post-Induction High Adalimumab Drug Levels Predict Biological Remission at Week 24 in Patients With Crohn's Disease

INTRODUCTION

We investigated whether early adalimumab drug levels (ADL) at week 4 predicted biological remission at week 24.

METHODS

In a prospective study, we assessed clinical and biological remission at weeks 0, 4, 12, and 24 after induction of adalimumab in 33 patients with Crohn's disease. Disease activity was determined by the Harvey-Bradshaw Index, ileocolonoscopy reports, cross-sectional imaging, C-reactive protein (CRP), and fecal calprotectin (FC) levels. Clinical remission was defined as Harvey-Bradshaw Index <5. Biological remission was defined as a combination of FC < 200 μg/g and CRP <5 μg/mL. ADL trough levels were tested using a liquid phase, mobility shift assay.

RESULTS

At 24 weeks, 18/33 (55%) of the patients were with biological remission. Ten (30%) patients required dose escalation or withdrawal from adalimumab by week 24 because of lack of response and exhibited significantly higher FC (P = 0.003) and CRP (P = 0.002). ADL levels at week 4 (19.8 μg/mL vs 10.2 μg/mL, P = 0.001) were significantly higher in patients with biological remission vs nonresponders at week 24. ADL levels at week 4 were a good predictor of biological remission at week 24, with area under the curve 0.86, 95% confidence interval (1.1; 1.67) and for combined biological and clinical remission, with area under the curve 0.8. The best ADL cutoff at week 4 that predicted biological remission at week 24 was 13.9 μg/mL (sensitivity 94.4% and specificity 73.3%).

DISCUSSION

In individuals with Crohn's disease, higher adalimumab drug levels at week 4 (>13.9 μg/mL) were significantly associated with biological remission at week 24.

Subcutaneous golimumab induced and maintained clinical response in a child with a biological-experienced steroid-refractory flare of ulcerative colitis: A case report

INTRODUCTION

Golimumab is a fully human antitumor necrosis monoclonal antibody that can be administered by either subcutaneous injection or intravenous infusion. Golimumab is approved for the treatment of the adults with rheumatic diseases, and ulcerative colitis, Whereas in children, golimumab is indicated only for the treatment of active polyarticular juvenile idiopathic arthritis. We have written on the off-label use of subcutaneous golimumab, which helped to induce and maintain remission on a low-weight biologically experienced child with steroid-refractory ulcerative colitis flare.

PATIENT CONCERNS

A 13-year-old pancolitis Syrian boy presented with abdominal pain and six to seven times bloody diarrhea. The child had treated with mesalamine 80 mg/kg/day, azathioprine 2.5 mg/kg/day, infliximab with an induction dose of 5 mg/kg at weeks 0, 2, and 6 followed by 5 mg/kg every 8 weeks. Infliximab did not maintain remission as the patient suffered from two flares that required hospital admission, intravenous corticosteroids, and infliximab escalation. Initial tests disclosed leukocytosis, anemia, hypoalbuminemia, an elevation in C-reactive protein and fecal calprotectin. All Stool studies were negative including routine stool cultures, Clostridium difficile toxin, Escherichia coli O157:H7, Cryptosporidium, and microscopy for ova and parasites. A sigmoidoscopy revealed multiple large ulcerations and spontaneous bleeding, colon biopsies were negative for Clostridium difficile and Cytomegalovirus. Cyclosporine, tacrolimus, and adalimumab were unavailable in Syria. Child's parents opposed colectomy as a treatment option.

DIAGNOSIS

Ulcerative colitis flare.

INTERVENTIONS

A subcutaneous golimumab with a loading dose of 200 mg at week 0, followed by 100 mg at week 2, then 50 mg every 4 weeks.

OUTCOMES

The patient achieved clinical remission by week sixth and maintained the remission for the next 90 weeks. At the time of last evaluation, tests, including C-reactive protein and fecal calprotectin, were within normal limits, complete colonoscopy revealed erythema, edema, mucosal friability, loss of vascular patterns, and pseudo-polyps. The Pediatric Ulcerative Colitis Activity Index and Mayo scores were 5 and 2 points, respectively. No adverse events were documented.

CONCLUSION

Golimumab has shown potential efficacy and safety in the treatment of ulcerative colitis in children which may indicate a significant future role for subcutaneous golimumab in pediatrics ulcerative colitis.

Is There a Role for Therapeutic Drug Monitoring in Patients with Hidradenitis Suppurativa on Tumor Necrosis Factor-α Inhibitors?

Tumor necrosis factor-α inhibitors, adalimumab and infliximab, are at the forefront of biologic therapy for the management of moderate-to-severe hidradenitis suppurativa, with adalimumab as currently the only approved medication for this condition. In treating patients, primary or secondary lack of response (also termed suboptimal response) is a major burden for both patients and healthcare systems and is a challenge with biologics in part owing to the development of anti-drug antibodies following treatment. To overcome this, therapeutic drug monitoring may be conducted proactively or reactively to a patient's suboptimal response guided by measurements of trough serum drug concentrations and levels of anti-drug antibodies. While strong evidence to support the utility of therapeutic drug monitoring exists in patients with inflammatory bowel disease, current information is limited in the context of hidradenitis suppurativa. We sought to summarize the available evidence and to present the role of therapeutic drug monitoring and other dose optimization strategies in improving clinical response in patients with hidradenitis suppurativa treated with tumor necrosis factor-α inhibitors.

Immunogenicity of biologic agents in rheumatology

Biologic agents have become a core component of therapeutic strategies for many inflammatory rheumatic diseases. However, perhaps reflecting the specificity and generally high affinity of biologic agents, these therapeutics have been used by rheumatologists with less consideration of their pharmacokinetics than that of conventional synthetic DMARDs. Immunogenicity was recognized as a potential limitation to the use of biologic agents at an early stage in their development, although regulatory guidance was relatively limited and assays to measure immunogenicity were less sophisticated than today. The advent of biosimilars has sparked a renewed interest in immunogenicity that has resulted in the development of increasingly sensitive assays, an enhanced appreciation of the pharmacokinetic consequences of immunogenicity and the development of comprehensive and specific guidance from regulatory authorities. As a result, rheumatologists have a greatly improved understanding of the field in general, including the factors responsible for immunogenicity, its potential clinical consequences and the implications for everyday treatment. In some specialties, immunogenicity testing is becoming a part of routine clinical management, but definitive evidence of its cost-effectiveness in rheumatology is awaited.

The current status of biological treatment for uveitis

INTRODUCTION

Noninfectious uveitis represents one of the leading causes of blindness in developed Countries, compromising patients' quality of life and social functioning. The main treatment goals are the control of ocular inflammation, to avert and treat sight-threatening complications, thus preserving and/or restoring visual function.

AREAS COVERED

This manuscript deals with systemic therapy with biologic drugs for noninfectious uveitis. An extensive literature search in the MEDLINE database (via PubMed) has been performed up to June 2020. The major classes of biologic molecules employed in ocular inflammatory diseases have been reviewed, focusing on TNF inhibitors, IL-1, IL-6, IL-17, IL-23 inhibitors, interferons, rituximab, and abatacept efficacy and safety. An overview of most recent developments in the field has been provided as well, with reference to the experience with JAK inhibitors and with biosimilar drugs.

EXPERT OPINION

The development of the concept of targeted therapy and the subsequent introduction of biologic molecules in clinical practice have revolutionized the prognosis of uveitis. The target of a rapid and sustained steroid-free remission of ocular inflammation should be pursued for all patients early in the disease course, in order to have a better chance to improve the final visual outcome.

Psychometric properties of measures of substance use: a systematic review and meta-analysis of reliability, validity and diagnostic test accuracy

Background

Synthesis of psychometric properties of substance use measures to identify patterns of use and substance use disorders remains limited. To address this gap, we sought to systematically evaluate the psychometric properties of measures to detect substance use and misuse.

Methods

We conducted a systematic review and meta-analysis of literature on measures of substance classes associated with HIV risk (heroin, methamphetamine, cocaine, ecstasy, alcohol) that were published in English before June 2016 that reported at least one of the following psychometric outcomes of interest: internal consistency (alpha), test-retest/inter-rater reliability (kappa), sensitivity, specificity, positive predictive value, and negative predictive value. We used meta-analytic techniques to generate pooled summary estimates for these outcomes using random effects and hierarchical logistic regression models.

Results

Findings across 387 paper revealed that overall, 65% of pooled estimates for alpha were in the range of fair-to-excellent; 44% of estimates for kappa were in the range of fair-to-excellent. In addition, 69, 97, 37 and 96% of pooled estimates for sensitivity, specificity, positive predictive value, and negative predictive value, respectively, were in the range of moderate-to-excellent.

Conclusion

We conclude that many substance use measures had pooled summary estimates that were at the fair/moderate-to-excellent range across different psychometric outcomes. Most scales were conducted in English, within the United States, highlighting the need to test and validate these measures in more diverse settings. Additionally, the majority of studies had high risk of bias, indicating a need for more studies with higher methodological quality.

Laboratory Monitoring of Biological Therapies in Rheumatology: The Role of Immunogenicity

Biological drugs, such as proteins and immunogens, are increasingly used to treat various diseases, including tumors and autoimmune diseases, and biological molecules have almost completely replaced synthetic drugs in rheumatology. Although biological treatments such as anti-tumor necrosis factor (TNF) drugs seem to be quite safe, they cause some undesirable effects, such as the onset of infections due to weakening of the immune system. Given the biological nature of these drugs, they might be recognized as extraneous; this would induce an immune reaction that neutralizes their effectiveness or lead to more serious consequences. Laboratories play a pivotal role in appropriate therapeutic management. The aim of this review was to underline the production of anti-drug antibodies during treatment with biological drugs and highlight the role of laboratories in ensuring appropriate use of these drugs.

Serum Levels of Infliximab and Anti-Infliximab Antibodies in Brazilian Patients with Crohn's Disease

OBJECTIVES

The aim of this study was to evaluate the quantitative serum level of infliximab (IFX) as well as the detection of anti-infliximab antibodies (ATIs) in patients with Crohn's disease (CD).

METHOD

Forty patients with CD under treatment at a tertiary center in southeastern Brazil were evaluated. Their use of infliximab was continuous and regular. We analyzed and compared the differences in the IFX and ATI levels between the patients with active CD (CDA) and those with CD in remission (CDR).

RESULTS

There was no difference in the IFX level between the CDA and CDR groups (p>0.05). Eighty percent of all patients had IFX levels above the therapeutic concentration (6-10 μg/mL). Two (9%) of the 22 patients with active disease and four (22.2%) of the 18 patients in remission had undetectable levels of IFX. Four (66.6%) of the six patients with undetectable levels of IFX had positive ATI levels; three of these patients were in remission, and one had active disease. In addition, the other two patients with undetectable levels of IFX presented ATI levels close to positivity (2.7 and 2.8 AU/ml). None of the patients with therapeutic or supratherapeutic IFX levels had positive ATI levels.

CONCLUSIONS

The undetectable levels of IFX correlated with the detection of ATIs, which was independent of disease activity. Immunogenicity was not the main factor for the loss of response to IFX in our study, and the majority of patients in both groups (CDA and CDR) had supratherapeutic levels of IFX.

Comparison of Point-of-Care and Classical Immunoassays for the Monitoring Infliximab and Antibodies Against Infliximab in IBD

OBJECTIVE

The primary objective is to assess whether the POC assays to measure infliximab residual trough level in the serum of IBD patients were non-inferior to the ELISA techniques available on the market, and to determine which of them was the most robust. The second is to compare three different ELISA kits for monitoring anti-infliximab antibodies (ATI).

METHODS

The assays were carried out on patients' sera using four ELISA kits from four different suppliers (three with a monoclonal antibody and one polyclonal) and two rapid techniques provided by BÜHLMANN (Quantum Blue^®) and R-Biopharm (Ridaquick) for monitoring infliximab levels. ATI were measured by three ELISA sets (Grifols, Theradiag, and R-Biopharm) which have different positivity limits and different units.

RESULTS

We measured infliximab residual level and ATI in the serum of 90 IBD patients (85 treated with infliximab and five with adalimumab). All of the infliximab assays were very well correlated when analyzed with Spearman nonparametric correlation (0.93 ≤ r ≤ 0.99), and the two POC assays were also excellently correlated (r = 0.98). The ATI monitoring kits revealed a correlation ranging from 0.73 to 0.96 when comparing positive and negative patients. When normalizing the quantitative values between the different ELISA tests (expressed arbitrarily by using multiples of the positivity limits defined by each supplier), the Spearman r coefficient ranged from 0.81 to 0.93.

CONCLUSION

The available evidence allows us to conclude that all of the infliximab monitoring assays correlate well and may be used for IFX monitoring; albeit variations in measured IFX concentration among different assays remain present, these assays could be interchangeable. The ATI monitoring techniques are all capable of detecting ATI-positive patients, but because of the difference in the positivity limits and the measurement units, it is better to follow a patient rate with one definite kit.