Evolution of Endoscopic Lesions in Steroid-Refractory Acute Severe Ulcerative Colitis Responding to Infliximab or Cyclosporine

Factors Associated With Response to Rescue Therapy in Acute Severe Ulcerative Colitis

BACKGROUND

Acute severe ulcerative colitis (ASUC) is a medical emergency for which colectomy is required in patients who do not respond to rescue therapy. While previous studies have predominantly focused on predicting outcome to first-line corticosteroid therapy, there is a need to understand the factors associated with response to rescue therapies in order to improve clinical outcomes. We reviewed the evidence regarding factors associated with response to rescue therapy in adults with ASUC and identified future directions for research.

METHODS

A systematic search of the literature was conducted, and 2 reviewers independently assessed studies for inclusion.

RESULTS

Of 3509 records screened, 101 completed studies were eligible for inclusion. We identified 42 clinical, hematological, biochemical, endoscopic, or pharmacological factors associated with response to rescue therapy. Older age (≥50 years), thiopurine experience, and cytomegalovirus or Clostridioides difficile infection were associated with a higher risk of nonresponse to rescue therapy. Biochemical factors associated with poorer response included an elevated C-reactive protein (CRP) ≥30mg/L on admission, hypoalbuminemia and an elevated ratio of CRP to albumin. Severe endoscopic findings, including a Mayo endoscopic score of 3 or Ulcerative Colitis Endoscopic Index of Severity ≥5, portended poorer outcomes. The role of fecal calprotectin and therapeutic value of measuring infliximab drug levels in ASUC remain to be defined.

CONCLUSIONS

Response to rescue therapy can be predicted by several specific factors, which would aid clinical decision-making. Existing and emerging factors should be integrated within predictive and prognostic models to help improve clinical outcomes.

Anti-TNFα in inflammatory bowel disease: from originators to biosimilars

The introduction of anti-tumor necrosis factor α (TNFα) biologics significantly innovated inflammatory bowel disease (IBD) treatment and increased medical costs. The recent expiration of patents of some anti-TNFα biologics (such as infliximab and adalimumab) facilitated the development of biosimilars. Comparable pharmacokinetic, efficacy, safety, and immunogenicity profiles between anti-TNFα originators and biosimilars were demonstrated in different studies. Anti-TNFα biosimilars hold promise for reducing the high cost of biologics and increasing patient access to biologics. In this review, we outline the current data on the use of anti-TNFα originators and biosimilars in patients with IBD, with a focus on the efficacy, safety, and immunogenicity profiles of infliximab and adalimumab biosimilars. The potential benefits, challenges, and future directions of anti-TNFα biosimilars are also discussed in the review.

Different levels of healing in inflammatory bowel diseases: mucosal, histological, transmural, barrier and complete healing

Mucosal healing on endoscopy has emerged as a key prognostic parameter in the management of patients with IBD (Crohn's disease, ulcerative colitis/UC) and can predict sustained clinical remission and resection-free survival. The structural basis for this type of mucosal healing is a progressive resolution of intestinal inflammation with associated healing of ulcers and improved epithelial barrier function. However, in some cases with mucosal healing on endoscopy, evidence of histological activity in mucosal biopsies has been observed. Subsequently, in UC, a second, deeper type of mucosal healing, denoted histological healing, was defined which requires the absence of active inflammation in mucosal biopsies. Both levels of mucosal healing should be considered as initial events in the resolution of gut inflammation in IBD rather than as indicators of complete transmural healing. In this review, the effects of anti-inflammatory, biological or immunosuppressive agents as well as small molecules on mucosal healing in clinical studies are highlighted. In addition, we focus on the implications of mucosal healing for clinical management of patients with IBD. Moreover, emerging techniques for the analysis of mucosal healing as well as potentially deeper levels of mucosal healing such as transmural healing and functional barrier healing of the mucosa are discussed. Although none of these new levels of healing indicate a definitive cure of the diseases, they make an important contribution to the assessment of patients' prognosis. The ultimate level of healing in IBD would be a resolution of all aspects of intestinal and extraintestinal inflammation (complete healing).

"Platelet-coated bullets" biomimetic nanoparticles to ameliorate experimental colitis by targeting endothelial cells

Intestinal vascular impairment is critical to the recovery of inflammatory bowel disease (IBD), and targeting vascular endothelial cells is a promising emerging therapeutic option. Considering the natural homing properties of platelets to activated vascular endothelium, platelet membrane-mimetic nanoparticles are expected to achieve precise treatment of IBD. Patchouli alcohol (PA) has proven efficacy in experimental colitis, yet its pharmacochemical properties require improvement to enhance efficacy. The rationale for targeting vascular lesions in IBD was analyzed by network pharmacology, and PA-affecting pathways were predicted. PA-encapsulated bio-nanoparticles (PNPs) were constructed to investigate the efficacy of agents on mouse intestinal microvascular endothelial cells (MIMVEC) inflammation model and dextran sulfate sodium (DSS)-induced acute mouse colitis model. PNPs were endocytosed by MIMVEC in vitro and efficiently enriched in inflamed colon. PNPs significantly alleviated the symptoms of experimental colitis and improved neutrophil infiltration. PNPs down-regulated LPS-induced aberrant elevation of il1β, tnfα and il6 mRNAs and reduced p65 phosphorylation in MIMVEC. Intracellular calcium expression, mitochondrial respiration and reactive oxygen species expression were also downregulated by PNPs. PNPs amplified the potency of PA as a calcium antagonist, restrained intracellular Ca²⁺ perturbations to prevent endothelial activation, which may block leukocyte recruitment in vivo to improve colitis.

Shenling Baizhu San ameliorates ulcerative colitis by regulating the gut microbiota and its tryptophan metabolites: A complementary medicine to mesalamine

ETHNOPHARMACOLOGICAL RELEVANCE

Shenling Baizhu San (SBS) is commonly employed to improve gastrointestinal dysfunction in patients with ulcerative colitis (UC) in China. SBS combined with mesalamine has been demonstrated to result in improve its curative effects without increasing any adverse reactions, but the underlying mechanism remains unclarified.

AIM OF THE STUDY

Our study aimed to illuminate the potential therapeutic effects and mechanisms of SBS, which is a medicine complementary to mesalamine, in the treatment of UC.

MATERIALS AND METHODS

A prospective cohort study was conducted to evaluate the efficacy of SBS as a complementary medicine to mesalamine for patients with UC (n = 48). The patients in the control group (n = 24) were given mesalamine alone, whereas those in the experimental group were administered mesalamine combined with SBS. The therapeutic outcome was assessed at 8 weeks. The structures of the gut microbiota (GMB) were characterized by 16S rRNA sequencing, and the microbial tryptophan metabolites were analyzed by UPLC-MS/MS to investigate the mechanism through which SBS achieves its effects.

RESULTS

Our results showed that the combination of SBS and mesalamine could significantly improve the clinical signs of UC by achieving mucosal healing and relieving colon damage. Interestingly, the combination of SBS and mesalamine could alter the GMB structures and increase the microbial levels of tryptophan metabolites, including indole-3-propionic acid and indole-3-acetic acid.

CONCLUSION

SBS combined with mesalamine is effective in improving the clinical and endoscopic outcomes of patients with UC. SBS, as a complementary therapy to conventional treatment, alleviates UC via the GMB-tryptophan metabolite axis.

A Review of the Totality of Evidence for the Development and Approval of ABP 710 (AVSOLA), an Infliximab Biosimilar

ABP 710 (AVSOLA^®) is a biosimilar to infliximab reference product (RP), a monoclonal antibody targeting tumor necrosis factor alpha (TNFα). It is approved in the USA and Canada for all the same indications as infliximab RP. Approval of ABP 710 was based on the totality of evidence (TOE) generated using a stepwise approach to assess its similarity with infliximab RP with regard to analytical (structural and functional) characteristics, pharmacokinetic parameters, and clinical efficacy and safety. ABP 710 was shown to be analytically similar to infliximab RP including in amino acid sequence, primary peptide structure, and glycan mapping and purity. ABP 710 was also demonstrated to be similar to infliximab RP with regard to functional characterization including in vitro binding, effector functions, and signaling pathways important for the mechanisms of action for clinical efficacy in multiple indications of immune-mediated inflammatory disorders including inflammatory bowel disease (IBD), especially binding to both soluble and membrane-bound TNFα. Pharmacokinetic similarity of ABP 710 with infliximab RP was demonstrated in healthy volunteers following a single 5 mg/kg intravenous dose. Comparative clinical efficacy of ABP 710 with infliximab RP was demonstrated in patients with rheumatoid arthritis. Safety and immunogenicity were also demonstrated to be similar for both ABP 710 and the RP. Overall, the TOE supported the conclusion that ABP 710 is highly similar to infliximab RP and supported scientific justification for extrapolation to all approved indications of infliximab RP, including IBD.

Comparing the clinical application values of the Degree of Ulcerative Colitis Burden of Luminal Inflammation (DUBLIN) score and Ulcerative Colitis Endoscopic Index of Severity (UCEIS) in patients with ulcerative colitis

Background

The significance of endoscopic evaluation in the diagnosis and management of ulcerative colitis (UC) has been widely recognized. Over the years, scholars have established several endoscopic scores. Herein, we assessed the clinical application value of the Mayo Endoscopic Subscore (Mayo ES), the Degree of Ulcerative Colitis Burden of Luminal Inflammation (DUBLIN) score, and the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score in UC patients, by comparing their correlation with disease activity and their predictive potential for treatment response and clinical outcomes.

Methods

UC patients hospitalized from September 2015 to September 2019 were retrospectively analysed. We employed Spearman's rank correlation coefficient to assess the linear association of the assessed endoscopic scores with the clinical parameters. The receiver-operating characteristic curve was applied to evaluate the predictive capabilities of the endoscopic scores for treatment escalation and 1-year readmission.

Results

A total of 178 patients were enrolled; most of them (82%) suffered moderate or severe colitis. Among them, 48 (27%) patients received treatment escalation and 59 (33%) were readmitted within 1 year. The DUBLIN and UCEIS scores demonstrated higher correlations with clinical parameters than the Mayo ES. The DUBLIN scores significantly differed between patients with mild, moderate, and severe colitis (all P < 0.001). The UCEIS scores demonstrated the best predictabilities for treatment escalation and 1-year readmission with an area under the curve of 0.88 and 0.75, respectively. Compared to the UCEIS and DUBLIN scores, the predictive capabilities of the Mayo ES for treatment escalation (both P < 0.001) and 1-year readmission (P < 0.001 and P = 0.002, respectively) were lower. The UCEIS scores exhibited a significant difference between the steroid-responsive group and the steroid-dependent or steroid-refractory group (both P < 0.001), while no significant differences in the Mayo ES and DUBLIN scores were found among the three groups (both P > 0.05).

Conclusion

This study demonstrates that both the DUBLIN and UCEIS scores outperform the Mayo ES in assessing disease severity and predicting treatment response and clinical outcomes in UC patients.

The pediatric ulcerative colitis activity index (PUCAI) predicts steroid-failure in adults with acute severe colitis

BACKGROUND

One-third of patients with acute severe ulcerative colitis (ASC) fail to respond to intravenous corticosteroids (IVCS) and require second-line therapy or colectomy. We aimed to explore the performance of the Pediatric Ulcerative Colitis Activity Index (PUCAI), for predicting response to IVCS in adults with ASC, and to base a two-step decision-making process for guiding the introduction of second-line therapy.

METHODS

This was a retrospective multicenter cohort study of adult patients with ASC. PUCAI score, Oxford criteria, and Swedish index were determined at baseline, day three and five of hospitalization, and discharge when outcomes were ascertained.

RESULTS

153 patients were included (mean age 34.7 ± 14.6, median disease duration 7.8 years [IQR 0-17.4]), of whom 51 (33%) required second-line therapy, and 23 (15%) eventually underwent colectomy by discharge. At days three and five, the median PUCAI scores were higher in non-responders compared with responders (55 [45-69] vs. 38 [25-55] at day 3, and 55 [36-65] vs. 20 [5-30] at day 5; both p < .001). The negative and positive predictive values (NPV and PPV) of IVCS failure were 76/63% for the Oxford criteria, 83/52% for the Swedish index as determined on day 3, and 73/100% for PUCAI ≥ 65 points on day five. The corresponding figures for PUCAI ≥ 45 at day 3 were 83/54%.

CONCLUSION

The PUCAI is a highly predictive tool for IVCS failure. PUCAI ≥ 45 on day 3 has an excellent NPV for IVCS failure indicating preparation for second-line therapy, and PUCAI ≥ 65 on day 5 has a high PPV to initiate the therapy.

Optimal Management of Acute Severe Ulcerative Colitis (ASUC): Challenges and Solutions

Acute severe colitis is a severe complication of ulcerative colitis, affecting approximately 20% of patients. For physicians, it remains a challenging condition to treat. Current treatment algorithms have diminished the mortality associated with acute severe ulcerative colitis (ASUC), but colectomy rates remain high (approximately 30%) despite advances in therapy. Colectomy in ASUC is particularly associated with important postoperative complications and morbidity. In this review, reasons for the inability to improve care and avoid evolution to colectomy for ASUC are explored and solutions that might lead to a better management of the disease are investigated.

How to manage: acute severe colitis

Acute severe ulcerative colitis (ASUC) is a medical emergency which is associated with significant morbidity and a mortality rate of 1%. ASUC requires prompt recognition and treatment. Optimal management includes admission to a specialist gastrointestinal unit and joint management with colorectal surgeons. Patients need to be screened for concomitant infections and thromboprophylaxis should be administered to mitigate against the elevated risk of thromboembolism. Corticosteroids are still the preferred initial medical therapy but approximately 30%-40% of patients fail steroid therapy and require rescue medical therapy with either infliximab or cyclosporine. Emergency colectomy is required in a timely manner for patients who fail rescue medical therapy to minimise the risk of adverse post-operative outcomes. We discuss current and emerging evidence in the management of ASUC and outline management approaches for clinicians involved in managing ASUC.