Background: Primary sclerosing cholangitis (PSC) is an immune-mediated, chronic cholestatic liver disease. Currently, liver transplantation is the only established life-saving treatment. Several studies have evaluated the effect of different biologic therapies on PSC with inconclusive findings. We conducted a systematic review and meta-analysis to assess the effects of biologics in PSC and associated inflammatory bowel disease (IBD). Methods: MEDLINE, Scopus, and Embase were searched up to July 31, 2023, for studies reporting the effects of biologics in patients with PSC-IBD. Effects of biologic therapy on alkaline phosphatase, total bilirubin, ulcerative colitis response score, and adverse events were calculated and expressed as standardized difference of means (SMD), proportions, and 95% CI using a random-effects model. Results: Six studies, including 411 PSC-IBD patients who received biologics, were included. Biologic treatment was associated with no change in alkaline phosphatase (SMD: 0.1, 95% CI: −0.07 −0.17, p=0.43), but a small and statistically significant increase in total bilirubin (SMD: 0.2, 95% CI: 0.05–0.35, p<0.01). 31.2% (95% CI: 23.8–39.7) of patients with IBD achieved endoscopic response, and there was a significant improvement in ulcerative colitis response score (SMD: −0.6,95% CI: −0.88 to 0.36, p<0.01). Furthermore, 17.6% (95% CI: 13.0–23.5) of patients experienced adverse events severe enough to discontinue therapy, and 29.9% (95% CI: 25.2–34.8) had a loss of response to biologics. Conclusions: Treatment of patients with PSC-IBD with biologics (vedolizumab, infliximab, and adalimumab) was not associated with improvement of biochemical markers of cholestasis. Biologics are effective in treating the colitis associated with PSC. Vedolizumab was associated with worsening liver enzymes in contrast to other biologics, a finding that warrants further study.
P860 The Costs of Inflammatory Bowel Diseases in High-Income Settings
Abstract Background Crohn’s disease (CD) and ulcerative colitis (UC), together known as inflammatory bowel diseases (IBD), affect approximately seven million people globally. The continuous rise in IBD prevalence and the aging of populations will inevitably lead to an increasing use of health care resources. In parallel with these trends, continuing innovations in IBD therapeutics, diagnostics, and preventatives are creating more options for IBD patients seeking to reduce their disease burden. These trends pose an imminent burden on health care systems and require that we identify modifiable cost drivers in IBD care and develop strategies for delivering equitable and affordable care for all patients. Methods This Lancet Gastroenterology & Hepatology Commission, consisting of a diverse faculty of health care professionals with expertise in the field of IBD and health economists, was formed to deliver an extensive summary of the literature and discuss key topics on the costs and cost-effectiveness of treating IBD in the present, and how this is likely to look in the future. Furthermore, it offers suggestions for how to deliver affordable IBD care in the coming years. The report’s focus was on high-income countries in Europe, North America, Australia and New Zealand, and Asia. Results The Commission drew together a wide range of expertise to discuss the current costs of IBD care, the drivers of increasing costs, as well as how to deliver affordable care for IBD in the future. The key conclusions are that (i) increases in health care costs must be evaluated against improved disease control and reductions in indirect costs, and (ii) that overarching systems for data interoperability, registries, and big data approaches must be established for continuous assessment of effectiveness, costs, and cost-effectiveness of care. International collaborations should be sought in order to evaluate novel models of care (such as value-based health care, including integrated health care and participatory health care models), as well as to improve the education and training of clinicians, patients, and policymakers. Measures to reduce the costs of IBD care are summarised in Table 1. Conclusion Increases in health care costs must be evaluated against improved disease control and reductions in indirect costs. Evaluations should be systematically aligned between countries and regions. Detailed analysis of the current epidemiology and the likely effects of changing IBD management on disease course and socioeconomic outcomes is essential; and will become even more imperative in the era of precision medicine, where complex biotechnologies will require expensive analyses, highly skilled personnel, and drug development for what may sometimes be relatively small patient groups.
The Mutational Landscape of Diffuse Large B Cell Lymphoma
Abstract Abstract 259 Despite recent progress, our understanding of the genomic basis of diffuse large B cell lymphoma (DLBCL) is incomplete. We have performed massively parallel whole exome sequencing with deep coverage of 57 primary tumor samples from patients with DLBCL and compared them to matched normal tissue to gain insight into the genetic defects leading to DLBCL. We define genes that are significantly enriched for somatic mutations, and thus, may be drivers of the disease. In addition to identifying genes that are well established to be functionally relevant in DLBCL, such as MyD88, CARD11, EZH2, and BCL2, we also discovered new genes that are significantly mutated that have not been described to play a role in DLBCL previously, such as MLL2, 3 and4 genes and PCLO. One of the challenges for the understanding of DLBCL biology is to determine the relative contribution of different genes with somatic mutations to the pathogenesis of the disease in an individual patient. Identification of functionally relevant mutated genes that only occur in a small number of patients based on prevalence alone may require thousands of patient samples. We therefore devise several strategies to discover genes with a high likelihood of functionally relevant mutations independent of their prevalence. Genes that do not co-occur with other mutated genes in the same patients, i.e. are mutually exclusive, are more likely to represent strong drivers, and to occur early in the development of DLBCL. We determined that TP53, BCL2, PIM1, and CD79B fall into this group. We apply pathway-focused analysis to identify mutated genes with low prevalence that are highly likely to have a functional impact. For instance, we identified G13D mutations in KRAS in two patients, and mutations in BRAF, NOTCH1, SOCS1, and PTEN in other patients that were previously described in other malignancies. These mutated genes are identified as part of significantly enriched gene sets, including the B cell receptor signaling/NFkB pathway, JAK/STAT, and antigen processing gene sets. In addition to these pathways that are important for physiological B cell activation, we find that many histone methyltransferases are enriched as a geneset in addition to MLL2. We identified a number of hotspots that are subject to somatic mutation. Our data imply that many of these hotspots may be targets of activation-induced cytidine deaminase (AID), which is usually involved in somatic hypermutation, suggesting a possible mechanism of how somatic mutation in DLBCL is mediated. In summary, our data define novel genetic defects in DLBCL by whole exome sequencing of 57 patients. Our data suggest that driver mutations may not be randomly distributed across the genome, but may occur in a directed fashion. We identified new genes not previously implicated in DLBCL, and have developed strategies to prioritize mutations that are most likely to be drivers of the disease. Disclosures: No relevant conflicts of interest to declare.
Discovery and prioritization of somatic mutations in diffuse large B-cell lymphoma (DLBCL) by whole-exome sequencing
To gain insight into the genomic basis of diffuse large B-cell lymphoma (DLBCL), we performed massively parallel whole-exome sequencing of 55 primary tumor samples from patients with DLBCL and matched normal tissue. We identified recurrent mutations in genes that are well known to be functionally relevant in DLBCL, including MYD88 , CARD11 , EZH2 , and CREBBP . We also identified somatic mutations in genes for which a functional role in DLBCL has not been previously suspected. These genes include MEF2B , MLL2 , BTG1 , GNA13 , ACTB , P2RY8 , PCLO , and TNFRSF14 . Further, we show that BCL2 mutations commonly occur in patients with BCL2 / IgH rearrangements as a result of somatic hypermutation normally occurring at the IgH locus. The BCL2 point mutations are primarily synonymous, and likely caused by activation-induced cytidine deaminase–mediated somatic hypermutation, as shown by comprehensive analysis of enrichment of mutations in WRCY target motifs. Those nonsynonymous mutations that are observed tend to be found outside of the functionally important BH domains of the protein, suggesting that strong negative selection against BCL2 loss-of-function mutations is at play. Last, by using an algorithm designed to identify likely functionally relevant but infrequent mutations, we identify KRAS , BRAF , and NOTCH1 as likely drivers of DLBCL pathogenesis in some patients. Our data provide an unbiased view of the landscape of mutations in DLBCL, and this in turn may point toward new therapeutic strategies for the disease.