Diet-omics in the Study of Urban and Rural Crohn disease Evolution (SOURCE) cohort

Crohn disease (CD) burden has increased with globalization/urbanization, and the rapid rise is attributed to environmental changes rather than genetic drift. The Study Of Urban and Rural CD Evolution (SOURCE, n = 380) has considered diet-omics domains simultaneously to detect complex interactions and identify potential beneficial and pathogenic factors linked with rural-urban transition and CD. We characterize exposures, diet, ileal transcriptomics, metabolomics, and microbiome in newly diagnosed CD patients and controls in rural and urban China and Israel. We show that time spent by rural residents in urban environments is linked with changes in gut microbial composition and metabolomics, which mirror those seen in CD. Ileal transcriptomics highlights personal metabolic and immune gene expression modules, that are directly linked to potential protective dietary exposures (coffee, manganese, vitamin D), fecal metabolites, and the microbiome. Bacteria-associated metabolites are primarily linked with host immune modules, whereas diet-linked metabolites are associated with host epithelial metabolic functions.

Prospective Observational Evaluation of the Time-Dependency of Adalimumab Immunogenicity and Drug Concentration in Ulcerative Colitis Patients: the POETIC II Study

BACKGROUND AND AIMS

Home self-injection of the human anti-tumour necrosis alpha [anti-TNFα] monoclonal adalimumab complicates prospective serial-sampling studies. Although a recent study examined adalimumab levels and immunogenicity in Crohn's disease [CD] patients, prospective real-world data from ulcerative colitis [UC] patients are lacking.

METHODS

A three-monthly home-visit programme from induction was established prospectively for UC patients. Clinical scores were determined at each visit, and sera were obtained for assessment of drug and anti-adalimumab antibody levels. Calprotectin was measured using a smartphone-based app. This cohort was compared to a parallel prospective cohort of adalimumab-treated CD patients [POETIC1].

RESULTS

Fifty UC patients starting adalimumab [median follow-up 28 weeks] were compared to 98 adalimumab-treated CD patients [median follow-up 44 weeks]. Only 11/50 UC patients [22%] continued treatment to the end of the follow-up compared with 50/98 [51%] CD patients (odds ratio [OR] = 0.27, p = 0.001). Loss of response was significantly more common in UC patients [OR = 3.2, p = 0.001]. Seventeen patients [34%] in the UC cohort developed anti-adalimumab antibodies, 9/17 [52.9%] as early as week 2. There was no difference between patient cohorts in the overall development of anti-adalimumab antibodies [34% vs 30.6%, respectively, OR = 1.67, p = 0.67], nor was there a difference in early immunogenicity [OR = 1.39, p = 0.35]. There was no difference in low drug levels [<3 µg/mL] between the two cohorts [OR = 0.87, p = 0.83].

CONCLUSIONS

Loss of response to adalimumab therapy was significantly more common in the UC compared to the CD cohort and was driven by a higher rate of non-immunogenic, pharmacodynamic parameters.

Baseline Peripheral Blood Mononuclear Cell Transcriptomics Before Ustekinumab Treatment Is Linked With Crohn's Disease Clinical Response at 1 Year

INTRODUCTION

Ustekinumab, a monoclonal antibody to the p40 subunit of interleukin (IL)-12 and IL-23, is used for Crohn's disease (CD), and the documented clinical remission rate after 1 year was observed in approximately 50% of patients. We aimed to identify predictors for a clinical response using peripheral blood obtained from patients with CD just before ustekinumab treatment initiation.

METHODS

RNA extraction from peripheral blood mononuclear cells was followed by mRNA paired-end sequencing. Differential gene expression was performed using DESeq2.

RESULTS

We processed samples from 36 adults with CD (13 men, 36%) obtained at baseline before starting ustekinumab treatment. Twenty-two of 36 (61%) were defined as responders and 14/36 (39%) as nonresponders after 1 year based on Physician Global Assessment. Differential gene expression between responders (n = 22) and nonresponders (n = 14) did not show a gene expression signature that passed false discovery rate (FDR) correction. However, the analyses identified 68 genes, including CXCL1/2/3, which were induced in nonresponders vs responders with P < 0.05 and fold change above 1.5. Functional annotation enrichments of these 68 genes using ToppGene indicated enrichment for cytokine activity (FDR = 1.98E-05), CXCR chemokine receptor binding (FDR = 2.11E-05), IL-10 signaling (FDR = 5.03E-07), genes encoding secreted soluble factors (FDR = 1.73E-05), and myeloid dendritic cells (FDR = 1.80E-08).

DISCUSSION

No substantial differences were found in peripheral blood mononuclear cell transcriptomics between responders and nonresponders. However, among the nonresponders, we noted an increased inflammatory response enriched for pathways linked with cytokine activity and chemokine receptor binding and innate myeloid signature. A larger cohort is required to validate and further explore these findings.

Serum matrix metalloproteinase-7: a potential biomarker in patients with Lynch Syndrome

BACKGROUND AND AIMS

The expression of tissue and serum matrix metalloproteinase-7 (MMP-7) was shown to be elevated both in colon cancer and dysplastic lesions. We aimed to evaluate, for the first time, its role as a diagnostic marker in Lynch syndrome (LS) carriers, a hereditary syndrome with predisposition to colon cancer.

METHODS

This was a case control study. Baseline serum MMP-7 levels were determined by ELISA in 40 colon cancer patients, 62 LS-carriers and 60 healthy controls. Retrieved data from medical files included demographics, background diseases, clinical data regarding tumor characteristics and genetic data. We assessed the association of serum MMP-7 levels with different variables in the study cohort using linear regression model adjusted for potential confounders.

RESULTS

In crude analysis, serum MMP-7 levels were significantly higher in colon cancer group compared to LS-carriers and controls [median (IQR) 4.1 ng/ml (2.7-6.0), 2.3 ng/ml (1.7-3.1), 2.5 ng/ml (1.5-3.7), respectively; p value - p < 0.001) while there was no difference between the two last groups (p value = 0.583). However, after adjusting for age and gender, LS-carriers' patients had 18% higher concentrations of serum MMP-7 compared to healthy controls (p value = 0.037), while colon cancer patients had 50% higher serum MMP-7 level in comparison to healthy controls (p value < 0.001). Additionally, age was positively associated with higher serum MMP-7 levels across all study groups (r = 0.67, p value < 0.001). In contrast, no correlation was observed between serum MMP-7 and either tumor staging and gene mutation.

CONCLUSIONS

Age-adjusted serum MMP-7 levels in asymptomatic LS carriers are higher than its levels in healthy population. While in colon cancer, MMP-7 higher level probably reflects the tumor burden and may have a prognostic effect, its significance and clinical applicability as a biomarker for tumorigenesis in LS is less clear and should be elucidated.

Do Vedolizumab trough Levels Predict the Outcome of Subsequent Therapy in Inflammatory Bowel Disease?

Background: Vedolizumab trough serum levels have been associated with clinical and endoscopic response in patients with inflammatory bowel disease (IBD). A recent study demonstrated that higher trough levels before dose escalation are associated with favorable outcomes. Objectives: We aimed to identify whether vedolizumab trough levels predict outcome of subsequent therapy. Methods: This retrospective study included IBD patients consecutively receiving vedolizumab therapy between November 2014 and June 2021. Only patients with a loss of response (LOR) to vedolizumab and available trough drug levels prior to therapy cessation were included. Clinical and endoscopic scores were recorded at 6 and 12 months post switching therapy. Results: Overall, 86 IBD patients (51 Crohn's disease, 35 ulcerative colitis) who discontinued vedolizumab were included; of those, 72 (83.7%) were due to LOR. Upon vedolizumab discontinuation, 66.3% of patients were switched to another biologic therapy. Trough vedolizumab levels at discontinuation due to LOR did not differ between patients with clinical response and LOR regarding subsequent therapy at 6 months [median 33.8 μg/mL (IQR 13.2-51.6) versus 31.7 μg/mL (IQR 9.1-64.8), p = 0.9] and at 12 months [median 29.6 μg/mL (IQR 14.3-51.6) versus 34.1 μg/mL (IQR 12.2-64.7), p = 0.6]. Patients progressing to subsequent surgery had numerically lower vedolizumab trough levels at LOR compared with patients who were treated with an additional medical therapy (median 14.3, IQR 4-28.2 μg/mL versus 33.5, IQR 13-51.6 μg/mL, p = 0.08). Conclusions: Vedolizumab trough levels upon LOR do not predict response to subsequent medical therapy; however, lower drug levels may suggest a more aggressive disease pattern and future need for surgery.

Distal Fecal Wash Host Transcriptomics Identifies Inflammation Throughout the Colon and Terminal Ileum

BACKGROUND & AIMS

Noninvasive modalities for assessing active endoscopic and histologic inflammation in Crohn's disease and ulcerative colitis patients are critically needed. Fecal wash host shed-cell transcriptomics has been shown to be a robust classifier of endoscopic and histologic inflammation in inflammatory bowel disease patients with distal colitis. Whether such fecal washes can inform on inflammatory processes occurring in more proximal intestinal segments is currently unknown.

METHODS

Fifty-nine inflammatory bowel disease patients and 50 controls were prospectively enrolled. Biopsy specimens and fecal washes from the distal colon, proximal colon, and terminal ileum were compared. Host transcriptomics were performed on the biopsy specimens and fecal washes obtained during colonoscopy at predefined locations throughout the colon and terminal ileum and results were associated with concurrent clinical, endoscopic, and histologic parameters.

RESULTS

We found that host transcriptomics of distal fecal washes robustly classify histologic inflammation in ileal and proximal colonic Crohn's disease, even without distal colonic involvement (area under the receiver operating characteristic curve, 0.94 ± 0.09). We further found that fecal washes consist of modules of co-expressed genes of immune, stromal, and epithelial origin that are indicative of endoscopic disease severity. Fecal wash host transcriptomics also capture expression of gene modules previously associated with a lack of response to biological therapies.

CONCLUSIONS

Our study establishes the accuracy of distal colonic fecal washes for identifying and scoring inflammatory processes throughout the entire ileal-colonic axis.

Characterization of blood-derived exosomal hTERT mRNA as a biomarker for colon cancer and Lynch syndrome

Background

Human telomerase reverse transcriptase (hTERT)- mRNA was shown to be elevated in exosomes derived from the sera of a variety of hematological and solid cancer patients. We aimed to evaluate its role as a diagnostic marker in patients with newly diagnosed colon cancer and in hereditary syndromes with predisposition to colon cancer.

Methods

hTERT -mRNA levels were determined in serum-derived exosomes from 88 patients with colon cancer, 71 Lynch-syndrome carriers with unknown active malignancies and 50 healthy controls. Data, including demographics, background diseases, clinical data regarding tumor characteristics and genetic data, were retrieved data from medical files.

Results

Patients with colon cancer had both higher exosomal hTERT mRNA levels and a higher proportion of patients with positive exosomal hTERT mRNA than controls (29.5% vs. 4%, respectively, P values < 0.001). Within the cancer group, patients with a metastatic disease had higher levels of telomerase mRNA than non-metastatic disease patients, and these levels correlated with CEA levels. Likewise, Lynch syndrome carriers had a higher proportion of positive exosomal hTERT mRNA than controls (21.1% vs. 4%, respectively, P value 0.008) but only a trend towards higher exosomal hTERT mRNA levels. Higher telomerase mRNA levels were not correlated with the mutated gene.

Conclusions

Exosomal serum hTERT –mRNA levels are associated with metastatic colon cancer and were also demonstrated in a subset of Lynch syndrome carriers. Its significance as a biomarker for developing malignancy should be elucidated.

Serum Syndecan-1: A Novel Biomarker for Pancreatic Ductal Adenocarcinoma

INTRODUCTION

Syndecan-1 (SDC1) has multiple functions in tumorigenesis in general and specifically in pancreatic cancer. We aimed to evaluate SDC1 as a diagnostic and prognostic biomarker in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

In this case-control study, patients newly diagnosed with a biopsy-proven PDAC were enrolled alongside healthy individuals in a derivation-validation cohort design. Serum SDC1 was measured by enzyme-linked immunoassay. The diagnostic accuracy of SDC1 levels for diagnosing PDAC was computed. A unified cohort enriched with additional early-stage patients with PDAC was used to evaluate the association of SDC1 with survival outcomes and patient characteristics.

RESULTS

In the derivation cohort, serum SDC1 levels were significantly higher in patients with PDAC (n = 39) compared with healthy controls (n = 20) (40.1 ng/mL, interquartile range 29.8-95.3 vs 25.6 ng/mL, interquartile range 17.1-29.8, respectively; P < 0.001). The receiver operating characteristic analysis area under the curve was 0.847 (95% confidence interval 0.747-0.947, P < 0.001). These results were replicated in a separate age-matched validation cohort (n = 38 PDAC, n = 38 controls; area under the curve 0.844, 95% confidence interval 0.757-0.932, P < 0.001). In the combined-enriched PDAC cohort (n = 110), using a cutoff of 35 ng/mL, the median overall 5-year survival between patients below and above this cutoff was not significantly different, although a trend for better survival after 1 year was found in the lower level group (P = 0.06). There were 12 of the 110 patients with PDAC (11%) who had normal CA 19-9 in the presence of elevated SDC1.

DISCUSSION

These findings suggest serum SDC1 as a promising novel biomarker for early blood-based diagnosis of pancreatic cancer.

Delaying an infliximab infusion by more than 3 days is associated with a significant reduction in trough levels but not with clinical worsening

BACKGROUND

Higher infliximab trough levels (TLs) correlate with better clinical, inflammatory, and endoscopic outcomes among inflammatory bowel disease (IBD) patients. Although standard scheduled infliximab therapy regimen consists of infusions at pre-defined time-points (weeks 0, 2, 6, and every 8 weeks), short-period deviations from therapeutic schedule are common in 'real life', but the pharmacokinetic impact of these deviations has not been explored. In this study, we aim to determine whether short-period deviations from infusion schedule affect infliximab-TL.

METHODS

A retrospective analysis of all IBD patients receiving infliximab maintenance therapy every 8 weeks was conducted in a tertiary medical center. Patients with anti-drug antibodies, deliberate interval shortening and <3 sequential maintenance sera available were excluded. Associations between time since last infusion and TL were studied. Statistical analysis was performed using generalized estimating equations.

RESULTS

Out of over 10,000 sera, 2088 sera of 302 maintenance period stable infliximab-therapy-patients met inclusion criteria (median TL 4.1 μg/mL, interquartile range (IQR) 2.3-6.5 μg/mL). A delay beyond 3 days in infusion schedule (n > 59 days since last infusion) was found to significantly affect TL (mean difference in TL 0.9 μg/mL, 95% confidence interval (CI): 0.03-1.9 μg/mL, p < 0.04). Furthermore, among patients with delayed infusions, 80% had TL below 5 μg/mL, in comparison to 55% of patients who were not late (odds ratio (OR): 2.81, CI: 2.02-3.92, p < 0.0001).

CONCLUSION

Real-life delays of ⩽3 days from infusion protocol can probably be allowed. Delays >3 days culminate in measurable decrease of TL, although effect on clinical outcome is unclear. This needs to be taken into account when interpreting drug-level test results.

SUMMARY

A total of 2088 sera of 302 maintenance period inflammatory bowel disease (IBD) patients treated with infliximab were analyzed, to assess effect of small deviations from infusion schedule on TLs. A significant decline in patients' trough level (TL) was noted as early as 3 days after scheduled infusion.

HBV-RNA, Quantitative HBsAg, Levels of HBV in Peripheral Lymphocytes and HBV Mutation Profiles in Chronic Hepatitis B

A comprehensive characterization of chronic HBV (CHB) patients is required to guide therapeutic decisions. The cumulative impact of classical and novel biomarkers on the clinical categorization of these patients has not been rigorously assessed. We determined plasma HBV-RNA and HBsAg levels, HBV in peripheral lymphocytes (PBMCs) and HBV mutation profiles in CHB patients. Patient demographics (n = 139) and classical HBV biomarkers were determined during a clinical routine. HBV-RNA in plasma and HBV-DNA in PBMCs were determined by RT-PCR. HBsAg levels were determined using Architect. In samples with HBV-DNA viral load >1000 IU/mL, genotype mutations in precore (PC), basal core promoter (BCP), HBsAg and Pol regions were determined by sequencing. Most patients (n = 126) were HBeAg-negative (HBeAgNeg) with significantly lower levels of HBV-RNA, HBV-DNA and HBsAg compared to HBeAg-positive (HBeAgPos) patients (p < 0.05). HBV genotype D prevailed (61/68), and >95% had BCP/PC mutations. Escape mutations were identified in 22.6% (13/63). HBeAgNeg patients with low levels of HBsAg (log IU ≤ 3) were older and were characterized by undetectable plasma HBV-DNA and undetectable HBV-RNA but not undetectable HBV-DNA in PBMCs compared to those with high HBsAg levels. In >50% of the studied HBeAgNeg patients (66/126), the quantitation of HBsAg and HBV-RNA may impact clinical decisions. In conclusion, the combined assessment of classical and novel serum biomarkers, especially in HBeAgNeg patients, which is the largest group of CHB patients in many regions, may assist in clinical decisions. Prospective studies are required to determine the real-time additive clinical advantage of these biomarkers.

Host transcriptome signatures in human faecal-washes predict histological remission in patients with IBD

BACKGROUND

Colonoscopy is the gold standard for evaluation of inflammation in inflammatory bowel diseases (IBDs), yet entails cumbersome preparations and risks of injury. Existing non-invasive prognostic tools are limited in their diagnostic power. Moreover, transcriptomics of colonic biopsies have been inconclusive in their association with clinical features.

AIMS

To assess the utility of host transcriptomics of faecal wash samples of patients with IBD compared with controls.

METHODS

In this prospective cohort study, we obtained biopsies and faecal-wash samples from patients with IBD and controls undergoing lower endoscopy. We performed RNAseq of biopsies and matching faecal-washes, and associated them with endoscopic and histological inflammation status. We also performed faecal mass-spectrometry proteomics on a subset of samples. We inferred cell compositions using computational deconvolution and used classification algorithms to identify informative genes.

RESULTS

We analysed biopsies and faecal washes from 39 patients (20 IBD, 19 controls). Host faecal-transcriptome carried information that was distinct from biopsy RNAseq and faecal proteomics. Transcriptomics of faecal washes, yet not of biopsies, from patients with histological inflammation were significantly correlated to one another (p=5.3×10-12). Faecal-transcriptome had significantly higher statistical power in identifying histological inflammation compared with transctiptome of intestinal biopsies (150 genes with area under the curve >0.9 in faecal samples vs 10 genes in biopsy RNAseq). These results were replicated in a validation cohort of 22 patients (10 IBD, 12 controls). Faecal samples were enriched in inflammatory monocytes, regulatory T cells, natural killer-cells and innate lymphoid cells.

CONCLUSIONS

Faecal wash host transcriptome is a statistically powerful biomarker reflecting histological inflammation. Furthermore, it opens the way to identifying important correlates and therapeutic targets that may be obscured using biopsy transcriptomics.

Immune function in newborns with in-utero exposure to anti-TNFα therapy

BACKGROUND AND AIM

Anti-TNFα is measurable in infants exposed in utero up to 12 months of age. Data about the exposure effect on the infant's adaptive immunity are limited. We aimed to prospectively evaluate the distribution and function of T and B cells, in infants of females with inflammatory bowel disease, in utero exposed to anti-TNFα or azathioprine.

METHODS

A prospective multi-center study conducted 2014-2017. Anti-TNFα levels were measured in cord blood, and at 3 and 12 months. T-cell repertoire and function were analyzed at 3 and 12 months by flow-cytometry, expression of diverse T cell receptors (TCR) and T-cell receptor excision circles (TREC) quantification assay. Serum immunoglobulins and antibodies for inactivated vaccines were measured at 12 months. Baseline clinical data were retrieved, and 2-monthly telephonic interviews were performed regarding child infections and growth.

RESULTS

24 pregnant females, age 30.6 (IQR 26.5-34.5) years were recruited, 20 with anti-TNFα (infliximab 8, adalimumab 12), and 4 with azathioprine treatment. Cord blood anti-TNFα was higher than maternal blood levels [4.3 (IQR 2.3-9.2) vs. 2.5 (IQR 1.3-9.7) mcg/ml], declining at 3 and 12 months. All infants had normal number of B-cells (n = 17), adequate levels of immunoglobulins (n = 14), and protecting antibody levels to Tetanus, Diphtheria, Hemophilus influenza-B and hepatitis B (n = 17). All had normal CD4+, CD8+ T-cells, and TREC numbers. TCR repertoire was polyclonal in 18/20 and slightly skewed in 2/20 infants. No serious infections requiring hospitalization were recorded.

CONCLUSION

We found that T-cell and B-cell immunity is fully mature and immune function is normal in infants exposed in utero to anti-TNFα, as in those exposed to azathioprine. Untreated controls and large-scale studies are needed to confirm these results.

Dose optimisation for Loss of Response to Vedolizumab- Pharmacokinetics and Immune Mechanisms

BACKGROUND

Real life data regarding pharmacokinetics of vedolizumab in patients needing dose optimisation are scarce. We set to examine whether pre-optimisation vedolizumab levels associate with therapy outcomes and which mechanisms explain the associations.

METHODS

A multicentre observational study assessed the outcome of dose increase in association with pre-escalation levels in vedolizumab-treated patients. SubsequentIy, α4β7 occupancy on peripheral blood [PB] and intestinal lamina propria [LP] tissues was investigated on various cellular subsets in patients undergoing lower endoscopy on infusion day. Cellular localisation of vedolizumab-bound α4β7 and effects on M1 and M2 macrophages were also explored.

RESULTS

A total of 161 inflammatory bowel disease [IBD] patients were included. Among 129/161 patients intensified during maintenance [Week 14 onward], pre-intensification trough levels were comparable or higher among those subsequently attaining post-optimisation clinical, biomarker, and endoscopic remission, compared with non-remitting patients [p = 0.09, 0.25, 0.04, respectively]. Similar results were demonstrated for those dose-optimised during induction [Week 6, n = 32]. In the immune sub-study [n = 43], free α4β7 receptors at trough were similarly low among patients with/without mucosal healing, on PB T cells [p = 0.15], LP T cells [p = 0.88], and on PB eosinophils [p = 0.08]. Integrin receptors on M1 and M2 macrophages were also saturated by low levels of vedolizumab and anti-inflammatory cytokine secretion was not increased. Co-localisation and dissociation experiments demonstrated membranal α4β7 receptors of two origins: non-internalised and newly generated α4β7, but re-binding was still complete at very low concentrations.

CONCLUSIONS

These results do not support pharmacokinetics as the mechanism responsible for loss of response to vedolizumab, nor do they support a need for higher drug concentration to enhance vedolizumab's immune effects. Higher pre-escalation levels may indicate less clearance [less severe disease] and higher likelihood of subsequent re-gained response, regardless of therapy escalation.

Lessons from intensified surveillance of viral hepatitis A, Israel, 2017 and 2018

Introduction

Universal vaccination of toddlers has led to very low hepatitis A (HAV) endemicity in Israel. However, sporadic outbreaks still occur, necessitating better surveillance.

Aim

To implement a comprehensive HAV surveillance programme.

Methods

In 2017 and 2018, sera from suspected HAV cases that tested positive for anti-HAV IgM antibodies were transferred to the Central Virology Laboratory (CVL) for molecular confirmation and genotyping. Sewage samples were collected in Israel and Palestine* and were molecularly analysed. All molecular (CVL), epidemiological (District Health Offices and Epidemiological Division) and clinical (treating physicians) data were combined and concordantly assessed.

Results

Overall, 146 cases (78 in 2017 and 68 in 2018, median age 34 years, 102 male) and 240 sewage samples were studied. Most cases (96%) were unvaccinated. In 2017, 89% of cases were male, 45% of whom were men who have sex with men (MSM). In 2018, 49% were male, but only 3% of them were MSM (p < 0.01). In 2017, 82% of cases and 63% of sewage samples were genotype 1A, phylogenetically associated with a global MSM-HAV outbreak. In 2018, 80% of cases and 71% of sewage samples were genotype 1B, related to the endemic strain previously identified in Israel and Palestine*. Environmental analysis revealed clustering of sewage and cases’ sequences, and country-wide circulation of HAV.

Conclusions

Molecular confirmation of HAV infection in cases and analysis of environmental samples, combined with clinical and epidemiological investigation, may improve HAV surveillance. Sequence-based typing of both clinical and sewage-derived samples could assist in understanding viral circulation.

Propagation of EBV-driven Lymphomatous Transformation of Peripheral Blood B Cells by Immunomodulators and Biologics Used in the Treatment of Inflammatory Bowel Disease

BACKGROUND

Immunomodulators and anti tumor-necrosis-α antibodies (anti-TNFs) have been implicated in increased risk of Epstein-Barr virus (EBV)-driven B-cell lymphoproliferative disorders in inflammatory bowel disease (IBD) patients. However, the underlying mechanisms are poorly understood.

METHODS

An in-vitro model of lymphoblastoid cell line (LCL) was established by co-incubation of EBV-infected human peripheral blood mononuclear cells (PBMC) with Cyclosporin-A (CSA). After 4 weeks, the resultant LCLs were analyzed by flow cytometry, telomerase activity assay, and next generation sequencing. Subsequently, LCLs were explored in the presence of therapeutic agents for IBD (anti-TNFs, vedolizumab, 6-Mercaptopurine [6MP], methotrexate). Epstein-Barr virus titers were quantitated by real-time polymerase chain reaction.

RESULTS

In cultures of PBMC with EBV and CSA, LCLs were characterized as an expanded, long lived population of CD58+CD23hi B-cells with high telomerase activity and clonal expansion. Upon addition to the cell cultures, LCL percentages were higher with infliximab (median 19.21%, P = 0.011), adalimumab (median 19.85%, P = 0.003), and early washed-out 6MP (median 30.57%, P = 0.043) compared with PBMC with EBV alone (median 9.61%). However, vedolizumab had no such effect (median 8.97%; P = 0.435). Additionally, LCL expansion was accompanied by increase in intracellular, rather than extracellular, EBV viral copies. Compared with PBMC with EBV alone, high levels of LCL were subsequently observed after triple depletion of NK cells, CD4+ T cells, and CD8+ T cells (median 52.8% vs 16.4%; P = 0.046) but also in cultures depleted solely of CD4+ T cells (median 30.7%, P = 0.046).

CONCLUSIONS

These results suggest that both anti-TNFs and 6MP, but not vedolizumab, propagate EBV-driven lymphoblastoid transformation in an in vitro model of lymphoma. This model may prove useful for studying mechanisms underlying proneoplastic viral immune interactions of novel drugs in IBD therapy.

Molecular Landscape of Anti-Drug Antibodies Reveals the Mechanism of the Immune Response Following Treatment With TNFα Antagonists

Drugs formulated from monoclonal antibodies (mAbs) are clinically effective in various diseases. Repeated administration of mAbs, however, elicits an immune response in the form of anti-drug-antibodies (ADA), thereby reducing the drug's efficacy. Notwithstanding their importance, the molecular landscape of ADA and the mechanisms involved in their formation are not fully understood. Using a newly developed quantitative bio-immunoassay, we found that ADA concentrations specific to TNFα antagonists can exceed extreme concentrations of 1 mg/ml with a wide range of neutralization capacity. Our data further suggest a preferential use of the λ light chain in a subset of neutralizing ADA. Moreover, we show that administration of TNFα antagonists result in a vaccine-like response whereby ADA formation is governed by the extrafollicular T cell-independent immune response. Our bio-immunoassay coupled with insights on the nature of the immune response can be leveraged to improve mAb immunogenicity assessment and facilitate improvement in therapeutic intervention strategies.

Serum MMP-9: a novel biomarker for prediction of clinical relapse in patients with quiescent Crohn's disease, a post hoc analysis

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) is a novel marker of intestinal inflammation. The aim of this study was to assess if serum MMP-9 levels predict clinical flare in patients with quiescent Crohn's disease (CD).

METHODS

This study was a post hoc analysis of a prospective observational study in which quiescent CD patients were included and followed until clinical relapse or the end of a 2-year follow-up period. Serial C-reactive protein (CRP) and fecal calprotectin (FC) levels were measured, and the patients underwent repeated capsule endoscopies (CEs) every 6 months. Small bowel inflammation was quantified by Lewis score (LS) for CE. A baseline magnetic resonance enterography was also performed, and MaRIA score was calculated. Serum MMP-9 levels in baseline blood samples were quantified by ELISA.

RESULTS

Out of 58 eligible enrolled patients, 16 had a flare. Higher levels of baseline MMP-9 were found in patients who developed subsequent symptomatic flare compared with patients who did not [median 661 ng/ml, 25-75 interquartile range (IQR; 478.2-1441.3) versus 525.5 ng/ ml (339-662.7), respectively, p = 0.01]. Patients with serum MMP-9 levels of 945 ng/ ml or higher were at increased risk for relapse within 24 months [area under the curve (AUC) of 0.72 [95% confidence interval (CI): 0.56-0.88]; hazard ratio 8.1 (95% CI 3.0-21.9, p < 0.001)]. Serum MMP-9 concentrations showed weak and moderate correlation to baseline LS and FC, respectively (r = 0.31, p = 0.02; r = 0.46, p < 0.001). No correlation was found between serum MMP-9 to CRP and MaRIA score.

CONCLUSIONS

Serum MMP-9 may be a promising biomarker for prediction of clinical flare in CD patients with quiescent disease.

Pharmacokinetics and Immune Reconstitution Following Discontinuation of Thiopurine Analogues: Implications for Drug Withdrawal Strategies

BACKGROUND AND AIMS

Discontinuation of thiopurine analogues is common prior to live vaccines, during infection or when de-escalating therapy. Data regarding clearance of active metabolites and immune re-constitution is scant. We aimed to determine drug elimination and immune re-constitution following thiopurine cessation.

METHODS

The elimination kinetics of 6-thioguanine nucleotides (6-TGN) were determined in nine inflammatory bowel disease [IBD] patients discontinuing thiopurines. Immune reconstitution was evaluated by toxic shock syndrome toxin 1 [TSST1] or anti-CD3 [OKT3]-induced CD4+ T-cell proliferation, following an initial exposure to TSST1 and 6-mercaptopurine [6MP], separately or combined.

RESULTS

All patients discontinuing thiopurines displayed first-order elimination kinetics of 6-TGN, with a median elimination half-life of 6.8 days [interquartile range 5.9-8.4]. Resting CD4+ T-cells exposed to 6MP preserved their response to subsequent polyclonal or Vβ2+-preferential stimulation. By contrast, exposure of TSST1-activated CD4+ T-cells to 6MP inhibited their subsequent Vβ2+clonal response to further stimulation [p = 0.008], whereas overall response to further non-Vβ2-selective stimulation with OKT3 was unaltered [p = 0.9].

CONCLUSIONS

Upon 6MP/azathioprine discontinuation, a 6-TGN elimination half-life of less than 10 days is expected in most patients. Immune reconstitution, however, may take longer for T-cell clones exposed to stimulation during thiopurine treatment. These findings may be useful when considering thiopurine cessation.

Association of Vedolizumab Level, Anti-Drug Antibodies, and α4β7 Occupancy With Response in Patients With Inflammatory Bowel Diseases

BACKGROUND & AIMS

There are few data available on the real-life pharmacokinetic and pharmacodynamics features of vedolizumab, a monoclonal antibody against integrin α4β7. We performed a prospective study of patients with inflammatory bowel diseases (IBDs) treated with vedolizumab to determine serum drug concentrations, formation of antivedolizumab antibodies (AVAs), and integrin α4β7 saturation.

METHODS

We performed a prospective study of 106 patients with IBD (67 with Crohn's disease and 39 with ulcerative colitis) treated with vedolizumab from September 2014 through March 2017 at 2 tertiary medical centers in Israel. Clinical data and serum samples were collected before and during induction and maintenance therapy. Clinical remission was defined as Harvey-Bradshaw index scores below 5 or as Simple Clinical Colitis Activity Index scores of 3 or less. We measured serum levels of vedolizumab, AVAs, and markers of inflammation. Peripheral blood mononuclear cells were obtained from some patients at designated trough time points and CD3+ CD45RO+ T cells were isolated from 36 samples. Cells were incubated with fluorescent-conjugated vedolizumab and flow cytometry was used to quantify α4β7 integrin saturation. We also performed flow cytometry analyses of CD3+ CD45RO+ lamina propria T cells isolated from intestinal mucosa of patients without IBD (non-IBD controls, n = 6), patients with IBD not treated with vedolizumab (untreated IBD controls, n = 8), and patients with IBD treated with vedolizumab (n = 15).

RESULTS

Clinical remission was achieved by 48 of 106 patients (45%) by week 6 and 50 of 106 patients (48%) by week 14 of treatment. The median level of vedolizumab at week 6 was higher in patients in clinical remission (40.2 μg/mL) than in patients with active disease (29.7 μg/mL; P = .05). The median serum level of vedolizumab was significantly higher in patients with a normal level of C-reactive protein (21.8 μg/mL vedolizumab) vs the level in those with a high level of C-reactive protein (11.9 μg/mL vedolizumab) during maintenance treatment (P = .0006). The other clinical outcomes measured were not associated with median serum level of vedolizumab at any time point examined. AVAs were detected in 17% of patients during induction therapy and 3% of patients during maintenance therapy, but did not correlate with clinical outcomes. Flow-cytometry analysis of peripheral blood memory T cells (n = 36) showed near-complete occupancy of α4β7 integrin at weeks 2 and 14 and during the maintenance phase, regardless of response status or drug levels. Most intestinal CD3+CD45RO+ memory T cells of healthy and IBD controls expressed α4β7 (72%; interquartile range, 56%-81%). In contrast, free α4β7 was detectable on only 5.6% of intestinal memory cells (interquartile range, 4.4%-11.2%) (P < .0001) from vedolizumab-treated patients, regardless of response.

CONCLUSIONS

In a prospective study of real-life patients with IBD, we associated vedolizumab drug levels with remission and inflammatory marker level. Integrin α4β7 was blocked in almost all T cells from patients treated with vedolizumab, regardless of serum level of the drug or response to treatment. These findings indicate a need to explore alternative mechanisms that prevent response to vedolizumab.

Safety, efficacy and pharmacokinetics of vedolizumab in patients with simultaneous exposure to an anti-tumour necrosis factor

BACKGROUND

Data on combination-biologic treatment in (IBD) are still scant.

AIM

To explore outcomes of patients co-exposed to anti-TNF and vedolizumab.

METHODS

Patients starting vedolizumab having measurable anti-TNF levels after recently stopping adalimumab/infliximab ('VDZ-aTNF' group), were compared with control vedolizumab patients in a retrospective 1:2 matched case-control study.

RESULTS

Seventy-five patients were included (25 VDZ-aTNF, 50 VDZ). Adverse events were experienced by 9/25 VDZ-aTNF compared to 13/50 VDZ patients (P = 0.4, follow-up 14 weeks in all). Week 14 clinical remission was attained in 10/25 (40%) of VDZ-aTNF patients versus 23/50 (46%) of VDZ patients (OR = 0.8, 95% CI 0.3-2.1, P = 0.6) and clinical response in 19/25 (76%) versus 39/50 (78%) respectively (OR = 0.9, 95% CI 0.3-2.7, P = 0.8). Corticosteroid-free remission and corticosteroid-free response were experienced by 30% and 54%, respectively, of the entire cohort, and were similar between the two groups. Vedolizumab drug concentrations at week 2, 6 and 14 were similar among VDZ-aTNF and VDZ patients (P > 0.5). Multi-variable analysis showed independent association of some vedolizumab drug-levels time-points with baseline albumin and weight, but not with anti-TNF co-exposure. In a prospective study of a separate cohort of patients starting infliximab (n = 12), the percentage of α4β7+ memory T cells, slightly but nonsignificantly increased throughout weeks 0, 2 to 14 (26 ± 2.3%, 27.8 ± 2.9%, 29.5 ± 2.6% respectively, P = 0.06).

CONCLUSIONS

Vedolizumab/anti-TNF co-exposure did not generate new safety signals during 14-weeks induction, nor did it reduce efficacy or alter vedolizumab pharmacokinetics. These observations may aid the design of future co-biologics trials and also suggest that a deliberate waiting-interval between anti-TNF cessation and subsequent vedolizumab initiation may not be warranted.

Characterization of hepatitis B and delta coinfection in Israel

BACKGROUND

Characteristics of hepatitis B (HBV) and delta (HDV) coinfection in various geographical regions, including Israel, remain unclear. Here we studied HDV seroprevalence in Israel, assessed HDV/HBV viral loads, circulating genotypes and hepatitis delta antigen (HDAg) conservation.

METHODS

Serological anti HDV IgG results from 8969 HBsAg positive individuals tested in 2010-2015 were retrospectively analyzed to determine HDV seroprevalence. In a cohort of HBV/HDV coinfected (n=58) and HBV monoinfected (n=27) patients, quantitative real-time PCR (qRT-PCR) and sequencing were performed to determine viral loads, genotypes and hepatitis delta antigen (HDAg) protein sequence.

RESULTS

6.5% (587/8969) of the HBsAg positive patients were positive for anti HDV antibodies. HDV viral load was >2 log copies/ml higher than HBV viral load in most of the coinfected patients with detectable HDV RNA (86%, 50/58). HDV genotype 1 was identified in all patients, most of whom did not express HBV. While 66.6% (4/6) of the HBV/HDV co-expressing patients carried HBV-D2 only 18.5% (5/27) of the HBV monoinfections had HBV-D2 (p=0.03). Higher genetic variability in the HDAg protein sequence was associated with higher HDV viral load.

CONCLUSIONS

The overall significant prevalence of HDV (6.5%) mandates HDV RNA testing for all coinfected patients. Patients positive for HDV RNA (characterized by low HBV DNA blood levels) carried HDV genotype 1. Taken together, the significant HDV seroprevalence and the lack of effective anti-HDV therapy, necessitates strict clinical surveillance especially in patients with higher HDV viral loads and increased viral evolution.

Vedolizumab Levels in Breast Milk of Nursing Mothers With Inflammatory Bowel Disease

INTRODUCTION

There are no data on the transfer of vedolizumab in breast milk of nursing mothers. We aimed to assess the presence of vedolizumab in breast milk of nursing inflammatory bowel disease [IBD] patients.

METHODS

This was a prospective observational study of vedolizumab-treated breastfeeding patients with IBD. Serum and breast milk samples were obtained at pre-defined tim -points. The in-house developed enzyme-linked immunosorbent assay [ELISA] for measuring vedolizumab in blood was adapted and validated for measurement of the drug in breast milk. The level of vedolizumab was also measured in breast milk of a control group of nursing healthy mothers.

RESULTS

Vedolizumab was undetectable in breast milk in IBD patients before the first infusion of vedolizumab [n = 3] and in all of the healthy controls [n = 5]. Vedolizumab was measurable in all lactating women who received vedolizumab [n = 5]. However, on serial measurements in breast milk after an infusion, drug levels did not surpass 480 ng/ml, which was roughly 1/100 of the comparable serum levels.

CONCLUSIONS

Vedolizumab can be detected in the breast milk of nursing mothers. Although more data are imperative, the concentrations of vedolizumab in breast milk are minute and are therefore unlikely to result in systemic or gastro-intestinal immune-suppression of the infant.

Early drug and anti-infliximab antibody levels for prediction of primary nonresponse to infliximab therapy

BACKGROUND

Primary nonresponse, defined as lack of clinical benefit during the induction phase, occurs in up to 30% of IBD patients treated with infliximab. The mechanisms underlying primary nonresponse have not yet been clearly defined.

AIM

To evaluate the association of early (week 2 and week 6) induction infliximab and anti-infliximab antibody levels with primary nonresponse.

METHODS

A retrospective observational case-control study of inflammatory bowel disease patients treated with infliximab and followed at Sheba Medical Center between 2009 and 2016 was performed. Pre-infusion infliximab and antibodies to infliximab (ATI) levels were measured by our previously described drug-tolerant ELISA assay.

RESULTS

Thirty-five primary nonresponders have been identified and matched with 105 primary responders (1:3 ratios). Both week 2 and week 6 infliximab levels were significantly lower among primary nonresponders compared to responders (week 2, 6: median level 7.2, 2.2 μg/mL vs 13.5, 9.5 μg/mL, P = .0019, P < .0001 respectively). Antibodies to infliximab appeared more frequently (either week 2 or 6, 68% vs 28% prevalence, P = .0004) and at higher levels in nonresponders compared to responders (week 2, 6: median ATI 7.3, 10.8 μg/mL-eq vs 3.8, 4.4 μg/mL-eq, P = .005, P = .008 respectively). Moreover, week 2 infliximab levels <6.8 μg/mL (AUC = 0.68, P = .002, sensitivity 50%, specificity 86%) and antibodies to infliximab levels >4.3 μg/mL-eq (AUC = 0.78, P = .0004, sensitivity 77%, specificity 71%) were predictive of primary nonresponse. Among the other clinical and demographic variables, higher baseline ulcerative colitis clinical score, infliximab monotherapy, prior adalimumab therapy and previous Crohn's disease-related surgeries were also associated with an increased risk of primary nonresponse.

CONCLUSIONS

Infliximab levels below 6.8 μg/mL and antibodies to infliximab levels above 4.3 μg/mL-eq before the second infusion are associated with primary nonresponse, especially among Crohn's disease patients.

The Association Between Drug Levels and Endoscopic Recurrence in Postoperative Patients with Crohn's Disease Treated with Tumor Necrosis Factor Inhibitors

BACKGROUND

Endoscopic recurrence is associated with a risk of clinical recurrence in patients with Crohn's disease after ileocecal or small bowel resection. Drug levels and presence of antidrug antibodies are associated with important clinical and endoscopic outcomes in patients with Crohn's disease treated with tumor necrosis factor inhibitors, such association was not evaluated for endoscopic postsurgical recurrence.

METHODS

Consecutive patients with Crohn's disease treated with anti-tumor necrosis factors after surgery were identified in the databases of the participating centers. Anti-tumor necrosis factor levels and antidrug antibodies were correlated with Rutgeerts score on colonoscopy performed ≥6 months postoperatively. Significant endoscopic recurrence (SER) was defined as Rutgeerts score >2.

RESULTS

Seventy-three consecutive patients (32-infliximab, 41-adalimumab) were included in the study. The colonoscopies were performed after a median of 15 (7-43) months after surgery and 8 (6-15) months from treatment onset. SER was demonstrated in 26/73 (35.6%) of the patients. The need for dose optimization, as well as trough infliximab levels (2.4 μg/mL [0.45-4.1] versus 1.1 (0-0.6), P = 0.008) and presence of antidrug antibodies (1/18 [5.6%] versus 10/14 [71.4%], P = 0.0001) were significantly associated with a risk of SER. The optimal cutoff infliximab level for prediction of SER was 1.8 μg/mL. No association between adalimumab levels and antiadalimumab antibodies was demonstrated.

Comparable Immune Function Inhibition by the Infliximab Biosimilar CT-P13: Implications for Treatment of Inflammatory Bowel Disease

BACKGROUND AND AIMS

CT-P13 is the first biosimilar monoclonal antibody to infliximab, and was recently approved in the European Union, Japan, Korea, and USA for all six indications of infliximab. However, studies directly assessing the biologic activity of CT-P13 versus inflximab in the context of inflammatory bowel disease [IBD] are still scanty. In the present study, we aimed to compare the biological activities of CT-P13 and infliximab with specific focus on intestinal cells so as to gain insight into the potential biosimilarity of these two agents for treatment of IBD.

METHODS

CT-P13 and infliximab were investigated and compared by in vitro experiments for their neutralisation ability of soluble tumour necrosis factor alpha [sTNFα] and membrane-bound tumour necrosis factor alpha [mTNFα], suppression of cytokine release by reverse signalling, induction of regulatory macrophages and wound healing, and antibody-dependent cell cytotoxicity [ADCC].

RESULTS

CT-P13 showed similar biological activities to infliximab as gauged by neutralisation of soluble TNFα, as well as blockade of apoptosis and suppression of pro-inflammatory cytokines in intestinal Caco-2 cells. Infliximab and CT-P13 equally induced apoptosis and outside-to-inside signals through transmembrane TNFα [tmTNFα]. Moreover, regulatory macrophage induction and ensuing wound healing were similarly exerted by CT-P13 and infliximab. However, neither CT-P13 nor infliximab exerted any significant ADCC of ex vivo-stimulated peripheral blood monocytes or lamina propria mononuclear cells from IBD patients.

CONCLUSIONS

These findings indicate that CT-P13 and infliximab exert highly similar biological activities in intestinal cells, and further support a mechanistic comparability of these two drugs in the treatment of IBD.

Addition of an immunomodulator can reverse antibody formation and loss of response in patients treated with adalimumab

BACKGROUND

Anti-adalimumab antibodies (AAA) are associated with loss of clinical response (LOR). Addition of an immunomodulator has been shown to reverse immunogenicity and regain response with infliximab monotherapy. Similar data on adalimumab are lacking.

AIM

To study the impact of immunomodulator addition on the emergence of AAA and LOR among adalimumab therapy patients.

METHODS

The databases of three tertiary medical centres were reviewed to identify patients who developed AAA during adalimumab monotherapy with resultant LOR, and received an immunomodulator as a salvage combination therapy. All sera were prospectively analysed using previously described ELISA assays. Clinical response was determined using appropriate clinical scores. Elimination of AAA, designated as 'sero-reversal', elevation of drug levels and regained clinical response were the sought outcomes.

RESULTS

Twenty-three patients (21 Crohn's disease, and 2 ulcerative colitis) developed AAA with subsequent LOR and were thereafter prescribed an immunomodulator as salvage therapy (thiopurine n = 14, methotrexate n = 9). Eleven patients (48%) underwent sero-reversal with gradual elimination of AAA, increase in drug trough levels and restoration of clinical response (median time to sero-reversal 5 months). In 12 patients (52%), immunogenicity and loss of response could not be reversed. There was no difference between responders and nonresponders in the type of immunomodulators used or baseline clinical characteristics.

CONCLUSIONS

In almost half of inflammatory bowel disease patients developing anti-adalimumab antibodies and loss of response, established immunogenicity of adalimumab can be gradually reversed by the addition of immunomodulator therapy with restoration of a clinico-biological response. However, these observations need to be confirmed with larger studies.

Addition of an immunomodulator can reverse antibody formation and loss of response in patients treated with adalimumab

BACKGROUND

Anti-adalimumab antibodies (AAA) are associated with loss of clinical response (LOR). Addition of an immunomodulator has been shown to reverse immunogenicity and regain response with infliximab monotherapy. Similar data on adalimumab are lacking.

AIM

To study the impact of immunomodulator addition on the emergence of AAA and LOR among adalimumab therapy patients.

METHODS

The databases of three tertiary medical centres were reviewed to identify patients who developed AAA during adalimumab monotherapy with resultant LOR, and received an immunomodulator as a salvage combination therapy. All sera were prospectively analysed using previously described ELISA assays. Clinical response was determined using appropriate clinical scores. Elimination of AAA, designated as 'sero-reversal', elevation of drug levels and regained clinical response were the sought outcomes.

RESULTS

Twenty-three patients (21 Crohn's disease, and 2 ulcerative colitis) developed AAA with subsequent LOR and were thereafter prescribed an immunomodulator as salvage therapy (thiopurine n = 14, methotrexate n = 9). Eleven patients (48%) underwent sero-reversal with gradual elimination of AAA, increase in drug trough levels and restoration of clinical response (median time to sero-reversal 5 months). In 12 patients (52%), immunogenicity and loss of response could not be reversed. There was no difference between responders and nonresponders in the type of immunomodulators used or baseline clinical characteristics.

CONCLUSIONS

In almost half of inflammatory bowel disease patients developing anti-adalimumab antibodies and loss of response, established immunogenicity of adalimumab can be gradually reversed by the addition of immunomodulator therapy with restoration of a clinico-biological response. However, these observations need to be confirmed with larger studies.

Cross-immunogenicity: antibodies to infliximab in Remicade-treated patients with IBD similarly recognise the biosimilar Remsima

OBJECTIVE

The cross-immunogenicity of the recently approved infliximab-biosimilar Remsima (CT-P13) with the originator drug Remicade is still unknown.

DESIGN

Sera of patients with IBD with or without measurable anti-Remicade antibodies to infliximab (ATI) were tested for their cross-reactivity to two batches of Remsima. Experiments were repeated after deglycosylation of Remicade/Remsima, IgG purification, excipients' dialysis and monomer purification by size exclusion chromatography. Anti-Remicade antibodies were tested for their functional inhibition of TNF-α binding by Remsima/Remicade by competition assay. Cross-reactivity of anti-adalimumab antibodies with Remicade/Remsima was also investigated.

RESULTS

125 patients' and controls' sera were tested (median age 31 years, IQR 24.5-39.5). All 56 anti-Remicade ATI-negative controls (14 healthy individuals, 42 patients with IBD) were also negative for anti-Remsima ATI. All 69 positive anti-Remicade IBD sera were cross-reactive with Remsima. ATI titres against Remicade or Remsima were strongly correlated (r values between 0.92 and 0.99, p<0.001 for all experiments, Spearman's correlation test). The background ELISA signal for Remsima was slightly higher compared with Remicade in negative controls (1.25±0.6 µg/mL vs 0.76±0.5 µg/mL, respectively, p<0.001), and persisted after deglycosylation, dialysis or protein size filtration, but abolished by IgG purification and significantly diminished by monomer purification. Anti-Remicade ATIs of patients with IBD (n=10) exerted similar functional inhibition on Remsima or Remicade TNF-α binding capacity (p=NS for all inhibition curve points). Antibodies-to-adalimumab in adalimumab-treated patients with IBD (n=7) did not cross-react with either Remicade or Remsima.

CONCLUSIONS

Anti-Remicade antibodies in patients with IBD recognise and functionally inhibit Remsima to a similar degree, suggesting similar immunogenicity and shared immunodominant epitopes on these two infliximab agents. In contrast, anti-adalimumab antibodies do not cross-react with Remsima or Remicade.

Induction infliximab levels among patients with acute severe ulcerative colitis compared with patients with moderately severe ulcerative colitis

BACKGROUND

Infliximab is effective as salvage therapy for patients with steroid refractory acute severe ulcerative colitis (UC). Although current data suggest that the pharmacokinetics of infliximab are influenced by inflammatory burden in patients with acute severe UC, data comparing infliximab trough levels in patients with acute severe UC vs. moderately severe UC are scarce.

AIM

To compare infliximab trough and anti-infliximab antibody levels at a standard fixed time-point during induction between patients with acute severe and moderately severe UC.

METHODS

A multi-centre retrospective study comparing infliximab drug and antibody levels 14 days after the first infusion in hospitalised acute severe UC versus out-patients with moderately severe UC was performed.

RESULTS

Sixteen acute severe UC patients, hospitalised between 2010-2015 and refractory to intravenous corticosteroids, were treated with infliximab 5 mg/kg salvage therapy. They were compared to 16 moderately severe UC out-patient controls. Mean infliximab trough levels at day 14 were significantly lower in patients with acute severe UC compared to moderately severe UC (7.15 ± 5.3 vs. 14.4 ± 11.2 μg/mL, P = 0.007). Seven patients (three acute severe and four moderate severe UC) were primary nonresponders to infliximab induction therapy. Infliximab level at day 14 did not differ between responders and nonresponders (9.8 ± 9 vs. 12.1 ± 10.6 μg/mL, respectively, P = N.S.). However, week 2 median antibody-to-infliximab levels were numerically higher among primary nonresponders (3.4 ± 5.7 vs. 1.2 ± 4 μg/mL-eq, respectively, P = 0.06).

CONCLUSIONS

Infliximab trough levels at day 14 were lower in patients with acute severe UC compared to moderately severe UC, possibly due to a higher inflammatory burden and/or increased drug clearance. However, drug levels at day 14 were not lower among nonresponders compared with responders. Controlled trials are warranted to examine whether an a-priori-intensified infliximab induction protocol will lead to an improved outcome in acute severe UC.

Optimizing Anti-TNF-α Therapy: Serum Levels of Infliximab and Adalimumab Are Associated With Mucosal Healing in Patients With Inflammatory Bowel Diseases

BACKGROUND & AIMS

It is not clear what serum levels of anti-tumor necrosis factor are associated with reduced intestinal inflammation in patients with inflammatory bowel disease (IBD). We aimed to identify serum levels of infliximab and adalimumab associated with mucosal healing in patients with IBD and to evaluate the putative gain in control of inflammation by incremental increases in drug levels.

METHODS

We performed a retrospective cross-sectional study of 145 patients with IBD treated with infliximab (n = 78) or adalimumab (n = 67) at a medical center in Israel from 2009 through 2014. We collected data from colonoscopy examinations; mucosal healing was defined as simple endoscopic score of <3 or a Mayo score ≤1. These data were compared with serum levels of anti-tumor necrosis factor agents, clinical scores, and levels of C-reactive protein.

RESULTS

Median serum levels of infliximab and adalimumab were significantly higher in patients with mucosal healing than patients with active disease (based on endoscopy) (for infliximab, 4.3 vs 1.7 μg/mL, P = .0002; for adalimumab, 6.2 vs 3.1 μg/mL, P = .01). Levels of infliximab above 5 μg/mL (area under the curve = 0.75; P < .0001) and levels of adalimumab above 7.1 μg/mL (area under the curve = 0.7; P = .004) identified patients with mucosal healing with 85% specificity. Increasing levels of infliximab beyond 8 μg/mL produced only minimal increases in the rate of mucosal healing, whereas the association between higher level of adalimumab and increased rate of mucosal healing reached a plateau at 12 μg/mL. In patients with measurable levels of infliximab >3 μg/mL, the presence of antibodies to infliximab was associated with a lower rate of mucosal healing compared with patients with similar drug level without antibodies (16% vs 50%, respectively; P = .003).

CONCLUSIONS

In a retrospective study, we found significant association between serum levels of anti-tumor necrosis factor agents and level of mucosal healing. We propose that serum levels of 6-10 μg/mL for infliximab and 8-12 μg/mL for adalimumab are required to achieve mucosal healing in 80%-90% of patients with IBD, and that this could be considered as a "therapeutic window." Exceeding these levels produces only a negligible gain in proportion of patients with mucosal healing.

Ashkenazi Jewish origin protects against formation of antibodies to infliximab and therapy failure

Infliximab is an anti-tumor necrosis factor (TNF) used for treatment of inflammatory bowel disease (IBD) as well as rheumatoid arthritis, psoriasis, and other inflammatory conditions. Antibodies to infliximab (ATI) develop in approximately 45% of infliximab-treated IBD patients and are correlated with loss of clinical response. Scarce data exist as to factors which predict infliximab immunogenicity.To investigate factors that may predict formation of antibodies to infliximab (ATI) and infliximab therapy failure an observational study of consecutive IBD patients treated with infliximab between 2009 and 2013 was performed. Trough levels of ATI were measured. Patients were monitored for disease activity using clinical activity indexes and were classified according to ATI formation and clinical response. All clinical and demographic parameters were analyzed for association with the designated outcomes.One hundred fifty-nine patients were included and 1505 sera were tested. On multivariate analysis, Jewish Ashkenazi ethnicity was protective against both development of ATI (odds ratio [OR] 0.35, 95% confidence interval [CI] 0.17-0.7, P = 0.005) and treatment failure (OR 0.29, 95% CI 0.13-0.66, P = 0.003). Concomitant immunomodulator therapy was also negatively associated with immunogenicity and infliximab therapy failure (OR 0.31, 95% CI 0.15-0.65, P = 0.002; OR 0.42 95% CI 0.18-0.99, p = 0.04, respectively), whereas episodic therapy was positively associated with both outcomes (OR 4.2 95% CI 1.07-16.1, p = 0.04, OR 4.45 95% CI 1.2-16.6, p = 0.026 respectively). All other variables, including IBD type, gender, weight, age, smoking status and disease duration, were not predictive of ATI formation or clinical failure. However, among Crohn's disease patients, a non-stricturing non-penetrating phenotype was protective against ATI formation (OR 0.4, 95% CI 0.14-0.96, p = 0.04). P = 0.04, respectively), whereas episodic/interrupted therapy was positively associated with both outcomes (OR 4.2, 95% CI 1.07-16.1, P = 0.04; OR 4.45, 95% CI 1.2-16.6, P = 0.026, respectively). All other variables, including IBD type, sex, weight, age, smoking status, and disease duration, were not predictive of ATI formation or clinical failure. However, among Crohn disease patients, a nonstricturing nonpenetrating phenotype was protective against ATI formation (OR 0.4, 95% CI 0.14-0.96, P = 0.04).Jewish Ashkenazi ethnicity is protective of ATI formation and infliximab therapy failure. These findings suggest a role for ethnicity, and implicitly for genetic predisposition, in modulating the risk of anti-TNF immunogenicity and treatment unresponsiveness.

Significance of low level infliximab in the absence of anti-infliximab antibodies

AIM: To evaluate the prevalence of double negative (DN) sera and the mechanisms responsible for DN status.

METHODS: Sera of inflammatory bowel disease patients treated with infliximab (IFX) were tested for drug/antibodies to infliximab (ATI) trough levels and the proportion of DN results was compared between a commercially available double antigen ELISA (with labeled IFX as the detection antibody) and an anti-lambda ELISA (with anti-human lambda chain detection antibody). Repeat testing with lower than customary serum dilution (1:10) was performed. Patients with DN status were matched with IFX+/ATI- controls and were followed-up for subsequent development of non-transient ATI to investigate if DN status precedes ATI.

RESULTS: Of 67 sera obtained at time of loss of response, only 6/67 (9%) were DN by anti-lambda ELISA compared to 27/67 (40%) with double antigen ELISA (P < 0.001, Fisher’s Exact test). Of the latter 27 sera, 22% were also DN by anti-lambda ELISA, whereas 44% were actually IFX positive (IFX+ATI-), 30% were ATI positive (IFX-ATI+) and 4% were double positive (IFX+ATI+). Re-testing using a 1:10 dilution converted most DN results into IFX+ and /or ATI+ status. Patients with DN status had shorter survival free of non-transient ATI compared with matched controls (log rank test, P < 0.001). In 9/30 (30%) of these patients, non transient ATI occurred before and after the event at which the DN serum was obtained, supporting the view that a DN result may represent a particular time-point along the two curves of ATI titer rise and infliximab drug level decline.

CONCLUSION: DN status may result from false negative detection of IFX or ATI by double antigen ELISA, suggesting a transitional state of low-level immunogenicity, rather than non-immunological clearance.

Expression of IL-2, IL-17 and TNF-alpha in patients with Crohn's disease treated with anti-TNF antibodies

BACKGROUND

The T cell cytokine IL-17 and the Th-17 pathway appear to have a role in the pathogenesis of inflammatory bowel diseases. IL-2 is a potent stimulator of lymphocyte proliferation and IL2/IL21 receptor polymorphisms have recently been associated with susceptibility to IBD.

AIMS

To evaluate the expression of IL-17, IL-2 and TNFα in Crohn's disease (CD) patients with and without anti-TNFs.

METHODS

Cytokine expression was evaluated by ELISA and intracellular staining of CD4(+) T-cells from the peripheral blood and lamina propria of CD patients and of non-IBD controls. The results were stratified by disease activity and anti-TNF treatment.

RESULTS

IL2 expression was significantly elevated in CD patients not treated with anti-TNFs in comparison to healthy controls (19.6% vs. 33.3%, P=0.03) and CD patients treated with anti-TNFs (20.4% vs. 33.3%, P=0.02), and similar in infliximab-treated patients and controls. IL17 expression was similar in CD patients and controls, and was not affected by anti-TNF therapy. TNFα expression in patients with active CD was increased compared to controls (35.5% vs 25.7%, P<0.005), and was significantly decreased in anti-TNF treated patients in comparison to CD patients without anti-TNFs (39.6% vs 26.2%, P=0.01).

CONCLUSIONS

Expression of IL2 was significantly decreased in anti-TNF-treated CD patients in comparison to non-treated CD patients and controls. This novel finding may indicate a further mechanism of anti-TNF therapy in CD. Expression of IL17 was not influenced by presence of CD or anti-TNF therapy, which may partly explain the failure of recent clinical trials investigating anti-IL17 therapy in CD.

The temporal evolution of antidrug antibodies in patients with inflammatory bowel disease treated with infliximab

OBJECTIVE

To characterise the temporal evolution of antibodies to infliximab (ATI).

DESIGN

Prospective observational study of infliximab-treated patients with inflammatory bowel disease between 2009 and 2012.

INTERVENTIONS

Trough levels of infliximab and ATI were measured before each infusion by anti-λ ELISA. Patients were monitored for disease activity by clinical activity indexes and for dose-intensification or infliximab cessation. The occurrence of transient ATI disappearing spontaneously without intervention was recorded separately.

RESULTS

125 patients were included (98 Crohn's disease, 27 ulcerative colitis, median follow-up 11.5±22 months) and 1119 sera were analysed for infliximab and ATI levels. Kaplan-Meier analysis showed that 42% of patients remained ATI-free by 4 years of treatment. Most (90%) of the patients who developed ATI did so within the first 12 months of therapy, whereas transient ATI were detected throughout the duration of infliximab therapy (p<0.001). ATI incidence was similar between patients who received infliximab previously (episodic/interrupted therapy patients, n=14) and scheduled-therapy patients (n=111). In the scheduled group, combination immunomodulator+infliximab resulted in longer ATI-free survival compared with monotherapy (p=0.003, logrank test). Survival free of clinical loss of response was enjoyed by 51% of patients, and serial measurements showed that ATI development often preceded the onset of clinical flare.

CONCLUSIONS

When followed prospectively, most patients who develop ATI do so within the first 12 months of therapy. This incidence is reduced by concomitant immunomodulator even in scheduled-therapy patients. In contrast, transient ATI, which are of little clinical significance, can appear haphazardly at any time during treatment. The onset of clinical loss of response may lag behind the appearance of anti-infliximab antibodies.

Addition of an immunomodulator to infliximab therapy eliminates antidrug antibodies in serum and restores clinical response of patients with inflammatory bowel disease

There are few therapeutic options for patients with inflammatory bowel disease who lose response to infliximab because they produced antibodies against the drug. We performed a retrospective analysis to investigate whether administration of immune modulators to 5 patients who developed antibodies to infliximab (ATI) restored response to this drug; 3 patients were given azathioprine/6-mercaptopurine and 2 patients were given methotrexate. Concentrations of infliximab and ATIs, and antitumor necrosis factor (TNF) activity, were analyzed using enzyme-linked immunosorbent assay-based competition assays of serum samples collected before and after patients were given the immunomodulator. In all patients, levels of ATIs gradually decreased and trough levels of infliximab increased; clinical responses were restored to all patients. In competition assays, immunomodulator-induced elimination of ATIs was associated with increased anti-TNF activity in serum. The addition of immunomodulators to therapy might be helpful to patients who have lost response to anti-TNF agents owing to formation of antidrug antibodies.

Clinical utility of antihuman lambda chain-based enzyme-linked immunosorbent assay (ELISA) versus double antigen ELISA for the detection of anti-infliximab antibodies

BACKGROUND

Anti-infliximab antibodies (ATIs) are associated with lower serum infliximab (IFX) trough levels and diminished clinical response. The current most prevalent method for detection of ATI is a double-antigen (DA) enzyme-linked immunosorbent assay (ELISA) utilizing IFX for ligand and detection antibody. Serum IFX interferes with ATI measurement in this method. An alternative ELISA using antihuman lambda chain (AHLC) antibody for ATI detection may be less amenable to this interference. The aim of our study was to compare the performance of AHLC-ATI versus DA-ATI for prediction of clinical response and evaluate the clinical significance of positive ATI in the presence of detectable IFX levels in IFX-treated inflammatory bowel disease (IBD) patients.

METHODS

In all, 63 patients' sera were analyzed for IFX levels and antibody levels by AHLC and DA. The results were compared with the clinical response to IFX. Percentage of patients with IFX+ATI+ status among IFX-treated patients and the clinical outcome of IFX+ATI+ patients were assessed.

RESULTS

ATIs were demonstrated in 22/63 (34.9%) and 18/63 (28.5%) sera of patients by AHLC and DA assay, respectively (P = 0.6). Detectable ATI and in IFX was detected in four patients (6.3%) by AHLC but not by DA assay. IFX+ATI+ status was documented in 8.7% of available sera and was associated with a trend for loss of response.

CONCLUSIONS

AHLC and DA ELISA are equally effective for ATI detection in patients with undetectable serum IFX. AHLC ELISA detects ATI in some patients with detectable serum IFX. This IFX+ATI+ status may be a harbinger of evolving loss of response to the drug.

The decline of anti-drug antibody titres after discontinuation of anti-TNFs: implications for predicting re-induction outcome in IBD

BACKGROUND

Anti-drug antibodies can be elicited by infliximab and adalimumab, but the rate of their decay after therapy is stopped is unknown.

AIM

To investigate the decline of anti-drug antibody titre after anti-TNF cessation, and to evaluate the clinical utility of anti-drug antibody measurement before anti-TNF re-induction.

METHODS

Inflammatory bowel disease (IBD) patients who stopped anti-TNF therapy and had measurable anti-drug antibodies were prospectively followed up by serial blood measurements of antibodies levels. The clinical outcome of a second cohort of patients who received re-induction by infliximab or adalimumab after a drug holiday >4 months was determined vis-à-vis their anti-drug antibodies status before re-induction.

RESULTS

The first cohort included 22 patients with anti-drug antibodies who were prospectively followed up after cessation of anti-TNF. Sixteen had antibodies-to-infliximab (ATI) and six had antibodies-to-adalimumab (ATA). ATI titres declined within 12 months to below detection levels in 13/16 infliximab-treated patients, whereas ATA titres became undetectable in only 2/6 adalimumab-treated patients (P = 0.04). The second cohort comprised 27 patients who resumed anti-TNFs (24 infliximab, 3 adalimumab). Of these, 3/5 patients with measurable anti-drug antibodies before re-induction experienced severe hypersensitivity reaction and/or nonresponse mandating drug-discontinuation, compared to 11/22 patients who were re-induced without measurable anti-drug antibodies (OR = 1.5, 95% CI 0.2-11, P = 0.7).

CONCLUSIONS

Antibodies to infliximab titres decline to undetectable levels within one year of cessation of infliximab in the majority of patients, whereas antibodies to adalimumab seem to persist longer after adalimumab discontinuation. Measuring antibodies to infliximab prior to infliximab re-induction is probably of little clinical utility, especially if more than a 12-month drug-holiday has elapsed.

Detection of infliximab in breast milk of nursing mothers with inflammatory bowel disease

INTRODUCTION

Limited data suggest the absence of infliximab in breast milk, thereby implying the safety of this drug during breast-feeding. We aimed to re-evaluate the presence of infliximab in breast milk of nursing IBD patients.

METHODS

Serum and breast milk were obtained post-partum from 3 breast-feeding patients with Crohn's disease before and after re-initiation of infliximab. ELISA assay was employed to measure infliximab level in maternal serum and in breast milk. The level of infliximab was also measured in breast milk of a control group of 8 nursing healthy mothers.

RESULTS

Infliximab was undetectable in breast milk prior to the first infusion and was also not measurable in 8 lactating women not exposed to infliximab. Infliximab levels in breast milk rose up to 101ng/ml within 2-3days of the infusion. These levels of infliximab in breast milk were roughly 1/200th of the level in blood.

CONCLUSIONS

In contrast with prior reports, infliximab can be detected in the breast milk of nursing mothers. The miniscule amounts of infliximab transferred in breast milk are unlikely to result in systemic immune-suppression of the infant. Nonetheless, local effects of this exposure on the neonates' intestine and potential immune sensitization or tolerization towards the drug can not be excluded and merit further investigations.

The immunogenic part of infliximab is the F(ab')2, but measuring antibodies to the intact infliximab molecule is more clinically useful

OBJECTIVES

To localise the immunogenic part of infliximab and evaluate the clinical usefulness of measuring antibodies against infliximab fragments.

DESIGN

Observational study.

SETTINGS

A specialised inflammatory bowel disease (IBD) centre in a tertiary hospital.

INTERVENTIONS

Serum was collected from patients with IBD and controls. Antibodies against whole infliximab (ATI) and against the digested Fc, F(ab')(2) and F(ab') fragments were measured by a specifically developed ELISA and by western blotting. A separate ELISA was used to determine infliximab levels in serum.

RESULTS

109 serum samples from 62 infliximab-treated patients were tested along with 64 control samples. Anti-F(ab')(2) antibodies were found in 28/42 (67%) samples with positive ATI, all from infliximab-exposed patients. Anti-F(ab')(2) antibodies were also present in 26 of the remaining 67 (39%) samples from exposed patients despite absent ATI. No specific anti-Fc antibodies were detected. Low trough infliximab level and high ATI level was found in 10/12 patients (83%) with complete loss of response to infliximab, but in only 5/14 patients (36%, p=0.02) who regained response to intensified infliximab regimen and in 2/24 patients (8%, p<0.001) in maintained remission while on 5 mg/kg/8 week infliximab treatment. Although Anti-F(ab')(2) antibodies showed similar test characteristics to ATI in patients losing response to infliximab, they were also detected in 61% of patients in maintained remission, thereby limiting their clinical usefulness. No cross reactivity to adalimumab was noted.

CONCLUSIONS

F(ab')(2) is the immunogenic fragment of infliximab. However, ATI level in serum--combined with measurement of trough infliximab level--is better correlated with the clinical response to infliximab or with its loss.

Early preservation of effector functions followed by eventual T cell memory depletion: a model for the delayed onset of the effect of thiopurines

OBJECTIVE

The onset of the effect of thiopurines is delayed for several months. The aim of this study was to investigate immune mechanisms for this delay.

METHODS

The effects of thiopurines on human peripheral blood T cells and on lamina propria lymphocytes were investigated for apoptosis induction by Annexin V/propidium iodide (PI) and for cytokine secretion by intracellular staining and ELISA assays. To investigate the mechanism of the effect of thiopurines in vivo, Balb/C mice were co-immunised with HEL/OVA (hen egg lysozyme/ovalbumin) antigens, and then repeatedly challenged by HEL only, while being treated by mercaptopurine or vehicle alone for either 4 or 20 weeks. The memory response of CD4+ splenocytes towards HEL/OVA was then determined by CFSE (carboxyfluorescein succinimidyl ester) dilution.

RESULTS

Thiopurines arrested the proliferation of stimulated T cells but did not enhance the apoptosis of either resting T cells or activated T cells until day 5 poststimulation. Despite the proliferation arrest, stimulated T cells successfully differentiated into effector cells, as evidenced by their capacity for proinflammatory cytokine secretion, potent adhesion and cytotoxicity. Prolonged mercaptopurine treatment of mice for 20 weeks selectively reduced the CD4+ memory response to a repeatedly encountered HEL antigen, but did not affect the T cell memory pool to the previously presented OVA antigen. A shorter, 4 weeks, treatment with mercaptopurine did not inhibit the memory response to either antigen.

CONCLUSIONS

T cells arrested from cycling by thiopurines can still differentiate into potent effector cells capable of propagating the inflammatory process. Thiopurine treatment results in depletion of antigen-specific memory T cells, but this effect is dependent upon repeated encounters with the antigen over a prolonged time course.

Functional voltage-gated sodium channels are expressed in human intestinal epithelial cells

BACKGROUND AND AIM

Local anesthetics which preferentially interact with voltage-gated sodium channels (VGSCs) were shown to have a clinical beneficial effect in ulcerative colitis and to regulate the secretion of inflammatory mediators from intestinal epithelial cells. However, expression of VGSCs in epithelial cells was not demonstrated. Herein we assessed whether intestinal epithelial cells express VGSCs.

METHODS

The expression of VGSCs in normal human colonic tissue and in the TNFalpha-treated or untreated intestinal epithelial cell line HT-29 was studied by immunofluorescence staining and FACS analysis, Western blot, immunohistochemistry, and RT-PCR using primers specific for several VGSC alpha subunits. The function of VGSCs was assessed by measuring changes in the membrane potential of the intestinal epithelial cells following incubation with lidocaine, veratridine, or both.

RESULTS

HT-29 cells were shown to express the VGSC alpha protein. mRNA analysis revealed the expression of nine of ten VGSC alpha isoforms. Immunohistochemical staining of normal colonic tissue confirmed the expression of VGSCs in colonic epithelial cells, smooth muscle cells, and nerves. Lidocaine induced membrane depolarization of HT-29 cells and its effect was blocked by veratridine.

CONCLUSION

Malignant and normal intestinal epithelial cells express functional VGSCs. These molecules may play a role in the regulation of inflammation in gut physiology and pathology.

Lidocaine down-regulates nuclear factor-kappaB signalling and inhibits cytokine production and T cell proliferation

Lidocaine is a commonly used local anaesthetic agent which has also been found to possess anti-inflammatory activity in several disorders. However, the mechanism of this effect has been little explored. The aim of this study was to investigate the effect of lidocaine on stimulated human T cells. The effect of lidocaine on Jurkat T cells was examined by enzyme-linked immunosorbent assay (ELISA) to determine secretion of interleukin (IL)-2, and by the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] viability assay. Tumour necrosis factor (TNF)-alpha and IL-2 mRNA expression was determined by reverse transcription-polymerase chain reaction. In addition, the effect of lidocaine on the proliferation of freshly isolated peripheral blood (PB) CD3(+) T cells was examined by carboxyfluorescein succinimidyl ester dilution. Apoptosis induction and cytokine production and secretion were determined by annexin V/PI assay, intracellular immunostaining and ELISA respectively. The results showed that lidocaine exerts a dose-dependent inhibition of IL-2 and TNF-alpha secretion by Jurkat T cells at the protein and mRNA levels. Moreover, lidocaine reduced nuclear factor-kappaB (NF-kappaB) signalling in clinically relevant concentrations. Similarly, proliferation of anti-CD3 stimulated PB T cells was abrogated significantly by lidocaine, and the percentage of interferon-gamma- and TNF-alpha-producing T cells was diminished after culture with this agent. In both experimental systems, lidocaine's effect was not mediated by cytotoxic mechanism, as no significant apoptosis or necrosis was demonstrated following co-culture of T cells with this drug. In conclusion, lidocaine's anti-inflammatory effect may be mediated by a drug-induced abrogation of T cell proliferation and cytokine secretion independent of cell death. These effects are mediated at least partly by inhibition of NF-kappaB signalling.

Qualité de vie et syndrome lipodystrophique chez les patients infectés par le VIH

AIM OF THE STUDY

The aim of this work is to show to what extent a psychosocial evaluation can lead bring to comprehension of the subjectivity of Quality of Life (QoL) among HIV-infected patients. Evaluation of QoL makes it possible to understand the link between the therapeutic effectiveness and the subjective evaluation of the treatment, but also to estimate more precisely how people live and take their treatment in the context of HIV infection.

METHOD

This work confronts the variation of QoL with the variation of several social and psychosocial parameters identified as of the components of the system, which is the subjective evaluation, and more precisely to a specific side effect of Highly Active AntiRetroviral Therapies (HAART): lipodystrophy syndrome that consists in body fat redistribution. This side effect could consist in an accumulation of body fat, or a loss of body fat or a combination of both symptoms. The analysis was made on the data from APROCO-COPILOTE cohort composed of HIV-infected patients initiating HAART.

RESULTS

Among a sample of 706 patients follow-up for three years and with available QoL data, we identified the variations of QoL according to the variation of this specific side effect and according to gender. Results show that lipodystrophy syndrome has a determinant impact on QoL different among male and female patients. Adjusted on clinical and socio-demographic characteristics, impaired women's QoL is associated with accumulation of body fat and impaired men's QoL is associated with loss of body fat.

CONCLUSION

These results underline the role of body image on subjective evaluation of QoL. The analysis of empirical data made it possible to highlight the social implication of the evaluation of QoL from the role of the social support, patient-provider relationship and the social context.

Impact of Newly Available Drugs on Clinical Progression in Patients with Virological Failure after Exposure to Three Classes of Antiretrovirals

Objective

To study the prognosis of HIV-infected patients with virological failure after exposure to three classes of antiretroviral drugs (ARVs).

Design

Cohort study. Setting: French Hospital Database on HIV.

Patients

Patients previously exposed to at least two nucleoside reverse transcriptase inhibitors (NRTIs), two protease inhibitors and one non-NRTI, with viral load (VL) values of >5000 copies/ml after the exposure criteria were met and a new treatment initiated between 1998 and 2001 with VL >5000 copies/ml.

Main outcome measures

Risk of new AIDS-defining-events (ADEs) or death from first introduction of a drug never used before occurring between 1998 and 2001 defined as baseline.

Results

The main baseline characteristics of the 1092 patients were: previous ADE in 49% of cases, median CD4 cell count 181 μl, median VL 4.9 log10 copies/ml, median duration of ARV therapy 5.0 years and previous exposure to a median of nine ARVs. The crude progression rates were 20.1/100 patient-years among patients included in 1998, 15.1 in 1999, 11.1 in 2000 and 8.6 in 2001. After adjustment for baseline characteristics, the calendar year of inclusion was associated with the risk of clinical progression ( P<0.001). When the types of newly available drugs used at baseline or during follow-up were introduced into the model, year of inclusion was no longer associated with the risk of clinical progression ( P=0.42), while exposure to amprenavir/r, lopinavir/r, abacavir or tenofovir was associated with a lower risk.

Conclusions

The clinical prognosis of heavily pretreated patients experiencing virological failure improved between 1998 and 2001, mainly thanks to the use of newly available drugs with more favourable resistance profiles.