Dr Vaishali Bhardwaj M.D. D.M DM Gastroenterology G B pant Hospital Delhi. 2013-2014 Assistant Professor GB Pant Hospital . 2014-Present Assistant Professor &Head Department Of Gastroenterology PGIMER RML Hospital She has various publications and has presented papers in both National and International conferences . She has been awarded Young Investigator Award twice at AOCC. Area of intrest: Heaptology &IBD.

IBD “STATE OF ART” Dr Vaishali Bhardwaj M.D.D.M(Gastroenterology) Head Department Of Gastroenterology PGIMER RML Hospital New Delhi

Introduction Chronic Inflammatory diseases of Bowel IBD Crohn’s Disease Ulcerative Colitis Microscopic Colitis Chronic Inflammatory diseases of Bowel Broad group of Disease

Remicade (Infliximab) We’ve come a long way… 1700-1900 1930 1940 1950 1960 1970 1980 1990 2000 2010 2020 Azathioprine Methotrexate IBD is recognized Prednisone Crohn’s and UC are described Mesalamine Remicade (Infliximab) Humira (Adalimumab) Giovanni Battista Morgagni in 1761 provided description of intestinal inflammation. Burrill Bernard Crohn Dr. Leon Ginzburg and Dr. Gordon Oppenheimer landmark paper describing Crohns. 1859 smuel wilkis ulcerative colitis. Nana savrtz 5 asa.,azad khan first time used in uc ,brookes introduced AZA.van deventer introduced infx to IBD. Cimzia (Certolizumab pegol) Tysabri (Natalizumab)

Idiopathic, chronic, relapsing, inflammatory conditions that are immunologically mediated Heterogeneous diseases characterized by various genetic abnormalities that lead to overly aggressive T-cell responses to a subset of commensal enteric bacteria. Environmental factors precipitate the onset or reactivation of disease.

Introduction Ulcerative Colitis Crohns Disease Affects rectum & extends proximally to variable extent of colon Affects only mucosa in continuous pattern Characterised by- Rectal bleeding, Frequent stools, Mucus discharge, Tenesmus& Lower abdominal pain. Chronic inflammation potentially involving any location of GIT . Transmural & often discontinuous. Characterised by- Fatigue Diarrhea with or without gross blood, Pain, weight loss, fever.

The famous SPM Triad Host Enviromment Agent All of us remember from our MBBs days the complex traid in pathogenesis of disease.

Triad for IBD Pathogenesis Genetics Immune Dysfunction Microbiome & Environmental

Khor B. Gardet A, et al. Nature 2011 Genetics in IBD Family History Significantly positive Particular ethnic groups with highly conserved genetic material more at risk GWAS identified- 118 genetic risk loci 28 common for UC and CD Khor B. Gardet A, et al. Nature 2011

Khor B. Gardet A, et al. Nature 2011 Role of Genetics in IBD Crohn’s Disease Ulcerative Colitis 71 risk loci 50-54% concordance in monozygotic twins 4% in dizygotic twins First degree relative-10x 47 risk loci 10-15% concordance in monozygotic twins No concordance in dizygotic First degree relative-2x Khor B. Gardet A, et al. Nature 2011

Innate immunity related NOD2 Genes Name Region CD UC Function Innate immunity related NOD2 16q12 Yes No Senses bacterial peptidoglycan to activate cell signalling ATG16L1 2q37 Component of autophagy complex IRGM 5q33 +/- Role in autophagy, required in IFN y related clearance of intracellular pathogens IL 23 – Th17 related IL23R 1p31 Unique component of heterodimeric IL23 receptor IL12B (p40) Component of IL23, common to IL12 STAT3 17q21 Major STAT downstream of various cytokines including IL-6,10,17,21,22,23 Others PTGER4 5p13 Receptor for inflammatory mediator PGE2 SLC22A4 5q31 Plasma membrane polyspecific organic anion transporter MHC 6p21 Distinct MHC class II asso. between UC and CD IL10 1q32 Immunosuppressive cytokine, central role in regulating intestinal inflammation INFG 12q15 Critical cytokine in innate and adaptive immunity against intracellular pathogens

NOD2 NOD2 : 2 CARD domains, a central NBD and a LRR domain LRR domain recognizes bacterial MDP : regulates NFkb activation and production of pro-inflammatory cytokines 3 variants in LRR domain : significant association with CD but no association with UC Nucleotide binding oligomerization domain 2./CARD 15 is caspase recuritment domain . One frameshift mutation leading to early truncation of protein,2 missense mutation

Role of NOD2 IBD Pathogenesis Exact mechanism unclear – proposed loss or gain of function Carriers of 1 NOD2 high risk variant : 2-4 fold increase risk of CD 2 NOD2 high risk variants : 20-40 fold increased risk Association with Ileal disease Younger onset Stricturing phenotype Gene product of nod2 is cytosolic protein that function as intracellular sensor of bacteria.. This protein binds to MDP component of bacterial peptidoglycan. Mutation in nod2 –momonuclear cells decreased activation of nfkbeta

Autophagy Genes Results in lysosomal degradation of organelles, unfolded proteins, or foreign extracellular material Key process required for maintaining cellular homeostasis after infection, mitochondrial damage, or ER stress Defects in autophagy shown to result in pathological inflammation Autophagy - important role in human inflammatory disorders by direct elimination of intracellular bacteria activation of PRR signaling involved in gut homeostasis and CD pathogenesis The term autophagy, or “self-eating,” results in the lysosomal degradation of organelles, unfolded proteins, or foreign extracellular material (Figure 2). It is a key process required for maintaining cellular homeostasis after infection, mitochondrial damage, or ER stress. Defects in autophagy have been shown to result in pathological inflammation and GWAS have linked two key genes in autophagy, ATG16L1 and IRGM, to CD[13,76]. An ATG16L1 hypomorphic mouse line that expresses about 1% of the normal level of ATG16L1 was shown to have Paneth cell granule abnormalities that are similar to those found in ileal resections in patients with CD that also carry the ATG16L1 gene variant[77]. While these hypomorphic ATG16L1 mice do not develop spontaneous colitis, they were found to have an increased susceptibility to DSS colitis[42]. However, when rederived virus free, these mice lost the Paneth cell pathology and ability to develop DSS induced colitis, which could be reversed by norovirus infection[42]. A recent study has reported that the ATG16L1 and NOD2 pathways may be interrelated[ 78]. In 2010, Cooney et al[78] demonstrated that NOD2 stimulation is capable of initiating autophagy in DCs and that for effective autophagy to occur, both intact NOD2 and ATG16L1 functions are required. IRGM belongs to a family of interferon-inducible immunity related GTPases (IRGs) that encodes a protein involved in multiple autophagocytic pathways including intracellular clearance of pathogens[79]. IRGM has been shown to play a role in autophagy during both Salmonella typhimurium and Mycobacterium bovis infections[79,80]. Another study in CD patients has demonstrated that autophagy is also important in the clearance of AIEC and that IRGM and ATG16L1

Autophagy Figure 2 Autophagy. A small volume of cytoplasm is enclosed by the autophagic isolation membrane, which forms the autophagosome. The outer membrane of the autophagosome then fuses with the lysosome where the cytoplasm derived materials are degraded

Microbiome Illusion for researchers Gut contains – 1014 microorganisms 500 species Lot of them still unexplored Crucial role in normal homeostasis as well as disease

Absolute numbers vary greatly, ranging from 1011 cells/g - Ascending colon ; 107–8  Distal Ileum & 102–3  Proximal Ileum & Jejunum.

Composition Bacteriodes Firmicutes 90% Proteobacteria Actinobacteria Fusobacteria

Microbiome IBD : dysregulated immune response to microbiota Theory : luminal bacteria provide stimulus for an inflammatory response Evidence CD diversion of feaces induces remission and infusion of feaces reactivates the disease D’Haens GR et al. Gastroenterology 1998 UC with active disease, antibiotics reduced mucosal inflammation Casellas F, Inflamm Bowel Dis 1998

Differences in Normal and Diseased Bowel Healthy subjects IBD subjects High biodiversity Low biodiversity Stable microbiota Dysbiosis Increased gut commensals Increased gut pathogens Higher firmicutes Lower firmicutes

Dysbiosis

IBD,s are chronic,Life-long We cannot just look at the short term induction therapy.

Goals of Therapy in the Inflammatory Bowel Diseases Symptom Improvement Improve the Future Reduce Hospitalization Reduce need for surgery Reduce social &occupational burden Mucosal Healing Targeted Therapy Against Inflammation in IBD Improve Safety and Tolerability of Medications The goal of therapy in IBD is to Induce Remission ;to maintain remission to maintain adequate nutrition ,minimize disease and treatment related complications.and improve QOL.

Rogler et al. Role of biological therapy for inflammatory bowel disease in developing countries. Gut 2012

Choice of Medical Therapy severity Mild, Moderate Severe Disease distribution E1,E2,E3 Disease Prior Therapy Side effects Complication Response

Current “Therapeutics Pyramid” Ulcerative colitis Surgery Infliximab(SEVERE) MTX AZA/6-MP Systemic Steroids (Moderate) Budenoside Antibiotics 5-ASA (MILD) Surgery Cyclosporin Systemic Steroids Infliximab Aminosaliysalates Crohn,s Disease Concept obsufactes induction maintanence stratgies.

Step Up Management Approach Remission achieved with less toxic drugs. Toxic therapy reserved for severe or refractory disease. Minimalize risk of adverse events Cost sparing?? Pateint need to “earn “most “ effective treatment. Decrease in QOL before pateint obtain optimal therapy High likelihood of surgery Disease is not modified.

Strategies & Targets of IBD Therapy Classic Anti inflammtory &Immunosupressants Immunomodulators & Inhibitors of Cascades Elimination of Antigen processing & presentation. Inhibition Of CD4 cell activation. Induction Of apoptosis Generation of regulatory T cells& effector cells. Inhibition of recruitment ,migration & Adhesion. Inhibition of GALT activation. Repair &restitution of barrier function.

When to Introduce Biologics?? The “Tipping Point “ may be Corticosteroids?

IBD Immunology 101 Mucosa Submucosa Blood Vessels

IBD Immunology 101 Mucosa Submucosa Blood Vessels

ANTI-TNF-α ANTIBODIES Best studied pro-inflammatory cytokine Produced by mononuclear cells Synthesis is induced through activation of cellular receptors, e.g., TLR4 Activation of TLR4 signaling induces activation of NF-κB and MAPK Differentiation of macrophages as well as inducing expression of pro-inflammatory cytokines, e.g., TNF-α, interleukin (IL)-6 and IL-12

Construct of Anti-TNF-α Biologic Agents Chimeric monoclonal antibody (75% human IgG1 isotype) Infliximab IgG1 Human recombinant antibody (100% human IgG1 isotype) Adalimumab IgG1 Humanized Fab’ fragment (95% human IgG1 isotype) Certolizumab Pegol PEG VH VL CH1 No Fc Mouse Human PEG, polyethylene glycol.

Infliximab Chimeric monoclonal antibody directed against tumor necrosis factor a. Active Ulcerative colitis Trials 1 & 2 (ACT 1, ACT 2) In each study, 364 patients with moderate-to-severe UC despite treatment with concurrent medications received placebo or infliximab (5 mg or 10 mg per kilogram of body weight) i.v at weeks 0, 2, and 6 and then every eight weeks through week 46 (in ACT 1) or week 22 (in ACT 2) Patients were followed for 54 weeks in ACT 1 and 30 weeks in ACT 2 Rutgeerts P et al. Infliximab for Induction and Maintenance Therapy for Ulcerative Colitis. N Engl J Med .

Patients with moderate-to-severe active ulcerative colitis treated with infliximab at weeks 0, 2, and 6 and every eight weeks thereafter were more likely to have a clinical response at weeks 8, 30, and 54 than were those receiving placebo

Adalimumab Adalimumab (ADA) is a fully humanized, , IG G1 monoclonal antibody,binds high affinity & specificity human TNF. ADA is administered subcutaneously Effective in inducing & maintaining remission moderate-to-severe Crohn’s disease& moderate-to-severe ulcerative colitis. Can be used in pt refractory to IFX No antibody formation

Certolizumab Pegol Pegylated conjugated Fab against TNF Does not contain an Fc portion Golimumab Human monoclonal antibody that targets TNF with a higher affinity than adalimumab.

Anti-TNF a Risks Immunogenecities (all biologicals) IFX specific Infusion reactions Class effects Drug induced lupus Injection site reactions (Ada ,C pegol) NHL (IFX+AZA) Serious infection -3% Oppourtunistic infection Demyelination

Anti-adhesion therapies Targets for Therapy Anti-adhesion therapies Chemokine Antagonists Anti-Integrin blockade Interleukin and Cytokine Antagonists IL-12/23 pathways Blockade of Intracellular Inflammation Control JAK-STAT Kinase Pathways

Chemokine CCR-9 Blockade of Cell Adhesion and Homing Cytokines Chemokines are selectively released to activate elements of inflammatory response Chemokine CCR9 has many function in intestinal inflammation Attracts T and B-cells to the site of inflammation CCR9 Binds to intestinal endothelium to help pull T-cells into the intestine Activates endothelial Integrins, permitting other inflammatory cells to enter the gut.

Blockade of Cell Adhesion and Homing Cytokines CCL-25 Ligand CCR9 Receptor

Compound CCX282-B Blockade of Cell Adhesion and Homing Cytokines Anti-chemokine CCR9 medication In Phase III Testing in Large Crohn’s Population Taken in pill form twice a day For Study in Crohn’s Disease

Block WBC Binding to Integrins Blockade of Adhesion Molecules: Vedolizumab Block WBC Binding to Integrins Anti-Integrin Coating

Leading Anti-Integrins In Development Blockade of Adhesion Molecules: Vedolizumab Leading Anti-Integrins In Development Vedolizumab rhuMAb Beta7 PF-00547659 (MAdCAM-1 Antagonist)

Vedolizumab Blockade of Adhesion Molecules: Vedolizumab Vedolizumab – antibody against one type of integrin Prevents binding of White Blood Cells (WBC) in the intestine Specific to the Intestine Being Studied in both Ulcerative Colitis and Crohn’s Given via IV infusion (in the vein) once a month

rhuMAb Beta7 Blockade of Adhesion Molecules: rhuMAb Beta7 Cheroutre and Madakamutil, Nat Rev Immunol 2004

Blockade of Cell-Activating Signals IL-12 Receptor IL-12/23 Ligand T-cell Interferon Dendritic cell IL-17 T-cells ACTIVATED

Blockade of Cell-Activating Signals: ustekinumab Ustekinumab – antibody blocking IL-12/23 Interleukins Blocks IL-12/23 mediated Activation of T-cells, Agents normalize IL-12/23 mediated signaling, cellular activation, and and cytokine production, thereby reducing inflammation Currently approved for treatment of Psoriasis (tradename: Stelera®) IV induction then Subcutaneous every 4 weeks.

Blockade of Cellular Inflammation Controls Interleukins Interleukins Attach to Receptors IL-12 Receptor JAK Binds to Activated Receptors JAK IL-12/23 Ligand JAK then Signals DNA Cell produces mediators of inflammation T-cell

Tofacitinib (CP-690550) Dampening Cytokine Response: JAK-Inhibitors Modulates signaling for several types of interleukins, Janus Kinases (JAK-1,2,3) mediate cellular response to many cytokines. JAK proteins are a MAJOR mechanism of directing the changes in cellular function to cause inflammation. Oral medication, Daily For Crohn’s Disease and Ulcerative Colitis

Exciting Agents Early in Development

Fecal Microbiota Transplantation FMT is introduction of fecal suspension derived from a healthy donor into GI Tract of diseased individual. FMT is no longer considered an alternative or last resort rather is gaining mainstream acceptance as valuable therapy with biological plausibility. FMT Transplant Material (TM) medically classified a human tissue is derived from healthy donor with no risk factors for transmissible disease/ any issue that may alter the cellular composition,esp antibiotic use.

Donor stool is delivered within few hours of passage undergoes - Dilution with normal saline Homogenization with a blender to achieve natural slurry Filtration to remove particulate material. Some institution use cryoprotection by freezing at -80 c till use.

Route of administration varies Naso -Duodenal Colonoscopy Enema Enteric coated capsule

Use in IBD is still in infancy . Mixed results are shown in various systemic reviews and RCT,s showing remission rates of 35%-40% in moderately active disease. Factors that could potentially determine final outcome - Host genotype Disease duration Antibiotic use associated with IBD onset Certain type of IBD associated Dysbiosis Donor characteristics

Currently FMT in IBD is restricted to investigational settings and several large clinical trials are underway.

Thank you