The document discusses biologic therapies for rheumatological conditions. It provides information on TNF antagonists that are approved for treating diseases like rheumatoid arthritis, spondyloarthropathies, and psoriasis. It discusses the mechanisms of action, pharmacokinetics, administration, and safety monitoring of TNF inhibitors like infliximab, etanercept, and adalimumab. The document also summarizes clinical trial data on the effectiveness of TNF inhibitors for conditions like Crohn's disease and ankylosing spondylitis.
8. Baeten et al Arthritis Rheum 2001 the effect of 3 infusions infliximab on the synovium evaluated between baseline on the left and at 12 weeks on the right
12. Infliximab in Crohn’s Disease Influence of Immunogenicity on Duration of Clinical Response (N=125) Baert F, et al. N Engl J Med. 2003;348:601-608. 65 38.5 0 10 20 30 40 50 60 70 Days of Clinical Response Patients With Infusion Reactions* Patients Without Infusion Reactions *Infliximab antibodies detected (61%); cumulative incidence of infusion rxs (27%). P <0.001
13. The incidence of lymphomas is increased in RA, but. The apparent increase in lymphomas in patients treated with TNF inhibitors may be due to confounding by indication — that is, that patients with severe disease who are (historically) most likely to develop lymphomas are also the ones most likely to receive TNF inhibitors. TNF-alpha plays an important role in tumor surveillance, particularly lymphoma. Because of this, Using TNF-alpha blocking agents in the treatment of rheumatoid arthritis (RA) may increase the risk of developing malignancies. Clinical trials of TNF inhibitors have not identified an increase in tumor (including lymphoma) risk, but are limited by short observation intervals and small cohorts. Here, Geborek et al Bladstrom, Jacobsson 2003 Lymphoma With TNF Antagonists
14. Lymphoma With TNF Antagonists 5.4 (2.6 – 10.0) 6.4 (1.7 – 16.3) 2.31 3.47 (1.59 – 6.59) SIR Lymphoma (95% conf interval) 18 mo (2.0 – 42.0) 10-19 mo (6.4) 21 mo (0.1 – 4.6) Mean Time to Onset (range) 1/9 1/3 3/6 Hodgkin's/ Non-Hodgkin's † 10 4 6 9 Total No. 2468 (4870) 1298 (2458) 3389 (8336) Treated/Exposure Pt-No. Pt-Yr Adalimumab Infliximab Etanercept † Majority diffuse large B cell SIR=standardized incidence ratio
15. Spondyloarthropathy family of disorders Inflammatory condition primarily affecting the spine which have in common the presence of sacroilitis, the presence of the HLA B27 gene and characteristic extra-articular manifestation. example: Ankylosing spondylitis Psoriatic arthritis Reactive arthritis Reiter syndrome Enteropathic arthritis (IBD associated arthritis) Undifferentiated Spondyloarthropathy
22. Modified new York criteria 1984 (Van der Linden) Radiological criterion sacroilitis, Grade=/>2 bilat / Grade3/4 unilat Clinical criterion (2 out of the following 3) 1-Low back pain and stiffness for >3months improve with exercise but not rest 2-Limitation of motion of lumber spine in both the sagital and frontal planes 3-Limitation of chest expansion relative to normal value for age and sex
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24. 2- BASDAI= Bath Ankylosing Spondylitis Disease Activity Index
27. life impact of AS Suffer pain and disability Socio-economic impact because onset at early age Unemployment (>50%) and high insurance 50% develop hip arthritis at early age and require Hip replacement which more often require reoperation due to heterotopic ossification of the hip prosthesis Mortality higher 1.5 than general population due to Cardiac valvular disease Amyloidosis Osteoporosis occurs early in disease increase fracture Annual health cost of one patient=6720$
28. Conventional therapy for AS Aim: relieve pain and stiffness Regular physiotherapy Hydrotherapy NSAIDs (improvement within 24 hours if there is failure to response Probability of suffering from AS is as low as 3%) long term use do not alters structural progression of the disease (use mainly as symptomatic relieve of pain and stiffness) Risk of GI upset use Naprxone / Use COX2 inhibitor ?celebrex support in the NASS and OPD rheumatology clinic NOTES:Treatment of peripheral and axial disease are different May be spontaneous remission later in life
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30. Sacroiliac Biopsy In Ankylosing Spondylitis Bollow M, Braun J. Ann Rheum Dis. 2000.
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36. Biologic Audit Rheumatology Department Watford G Hospital Dr R MUSA Dr A Hayee Margaret Brown
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38. Age & sex distribution On therapy - 13 female all Rheumatoid arthritis patients 9 male six Rheumatoid arthritis and three AS All the six suspended patients are female Age range RhA(35 - 80) and AS(22 - 69)
TNF Antagonists: Other Indications and Clinical Investigations There are a wide range of proven and potential clinical applications for TNF antagonists. Clinical trial results have confirmed the effectiveness of these preparations in Crohn's disease, psoriatic arthritis, psoriasis, ankylosing spondylitis, reactive arthritis, juvenile RA, and adult Still’s disease. TNF antagonists are currently being evaluated as treatment for vasculitis (eg, Wegener's disease, giant cell arteritis [GCA]), scleroderma, graft-versus-host disease, inflammatory myositis, interstitial lung disease, Sjogren’s syndrome, inflammatory eye and ear disease, asthma, hepatitis, sarcoidosis, Behcet's disease, and pyoderma gangrenosum.
Cytokine Signaling Pathways Involved in RA CD4+ T cells might initiate the disease process in RA. Activated by antigens, these cells stimulate monocytes, synovial fibroblasts, and macrophages to produce the key proinflammatory cytokines TNF- , IL-1, and IL-6 as well as to release matrix metalloproteinases (MMPs), enzymes that degrade connective tissue matrix. 1 TNF- and IL-1 also inhibit synovial fibroblasts from producing tissue inhibitors of MMPs. 2 These two actions by TNF- and IL-1, among others, are believed to result in the joint damage that occurs in RA. 1 Activated CD4+ T cells also contribute to joint damage by stimulating the development of osteoclasts by expressing osteoprotegerin ligands (OPGLs) and by stimulating B cells to produce immunoglobulins such as rheumatoid factor. 1 Activated macrophages, lymphocytes, and fibroblasts and their products can stimulate angiogenesis, a fact that may account for the increased vascularity of the synovium in rheumatoid joints. 1 Other cytokines involved in the complex cellular interactions that occur as part of the inflammatory process include IL-4, IL-10, IL-12, and IFN- . In addition, CD11 and CD69 cells are involved in the cell-surface signaling that leads to the production of cytokines. 1 Choy EHS, Panayi GS. Cytokine pathways and joint inflammation in rheumatoid arthritis. N Engl J Med . 2001;344:907-916. Shingu M, Nagai Y, Isayama T, Naono T, Nobunaga M, Nagai Y. The effects of cytokines on metalloproteinase inhibitors (TIMP) and collagenase production by human chondrocytes and TIMP production by synovial cells and endothelial cells. Clin Exp Immunol . 1993;94:145-149.
Biologic DMARDs There are substantial differences in pharmacokinetic properties among the biologic DMARDs being developed for the treatment of patients with RA. Etanercept is a soluble receptor formed from the fusion of two p75 TNF receptors to human immunoglobulin (IgG). Etanercept binds to TNF- and lymphotoxin (LT)- with an affinity of 10 10 M -1 . Because it has a half-life of 4.3 days, it is administered subcutaneously twice weekly (at a dose of 25 mg). 1 Infliximab is a chimeric TNF- monoclonal antibody (mAb) comprising about 75% human and 25% mouse protein. Infliximab binds to TNF- with an affinity of 1.8 x 10 9 M -1 . It has a half-life of 8 to 10 days and is administered intravenously in combination with MTX every 4 to 8 weeks (at a dose of 3 to 10 mg/kg). 2 Anakinra is a recombinant IL-1 receptor antagonist construct that binds to type I IL-1R with an affinity of 7.5 x 10 11 M -1 . Anakinra has a half-life of 4 to 6 hours and is administered subcutaneously once daily (at a dose of 100 mg). 3 Adalimumab is a fully human TNF- mAb that binds to TNF- with an affinity of 2.3 x 10 10 M -1 . Adalimumab has a half-life of approximately 2 weeks and is administered subcutaneously once every other week; the proposed dose is 40 mg eow. 4 Etanercept, infliximab, and adalimumab are produced in Chinese hamster ovary cells; anakinra is produced in an Escherichia coli expression system. 1. Enbrel ® (etanercept) [package insert]. Seattle, Wash: Immunex Corporation; 2002. 2. Remicade ® (infliximab) [package insert]. Malvern, Pa: Centocor, Inc; 2002. 3. Kineret ™ (anakinra) [package insert]. Thousand Oaks, Calif: Amgen Inc; 2002. 4. Salfeld J, Kaymakçalan Z, Tracey D. Generation of fully human anti-TNF antibody D2E7. Arthritis Rheum . 1998;41(suppl):S57. Abstract.
Inhibition of Cytokines Cytokines exert their damaging effects by binding to specific receptors, and there are several potential approaches that can be employed to block these effects. Cytokines can be neutralized through the use of antibodies or soluble receptors. With this approach, the cytokine never reaches the receptor on the cell of interest. This avenue for the treatment of RA has been taken with soluble TNF- receptor fusion proteins, soluble IL receptors, monoclonal antibodies against TNF- , and monoclonal antibodies against IL-6. Receptor antagonists or antibodies can bind to cytokine receptors on cells and prevent cytokines from binding. This blocks their actions on the cell in question. This approach to the treatment of RA has been taken with recombinant IL-1Ra and an antibody against the IL-6 receptor. Administration of anti-inflammatory cytokines can inhibit expression of inflammatory cytokines. This approach has been taken with IL-4 and IL-10. Choy EHS, Panayi GS. Cytokine pathways and joint inflammation in rheumatoid arthritis. N Engl J Med . 2001;344:907-916.
This slide demonstrates the effect of 3 infusions infliximab on the synovium evaluated between baseline on the left and at 12 weeks on the right Panels ab synovial lining hyperplasia cd vascularity ef neutrophil infiltration gh plasma cell infiltration
Baert F, Noman M, Vermeire S, et al. Influence of immunogenicity on the long-term efficacy of infliximab in Crohn's disease. N Engl J Med. 2003;348:601-608. Abstract: BACKGROUND: Treatment with infliximab, a chimeric monoclonal IgG1 antibody against tumor necrosis factor, can result in the formation of antibodies against infliximab. We evaluated the clinical significance of these antibodies in patients with Crohn's disease. METHODS: In a cohort of 125 consecutive patients with Crohn's disease who were treated with infliximab infusions, we evaluated the concentrations of infliximab and of antibodies against infliximab, clinical data, side effects (including infusion reactions), and the use of concomitant medications before and 4, 8, and 12 weeks after each infusion. RESULTS: A mean of 3.9 infusions (range, 1 to 17) per patient were administered over a mean period of 10 months. Antibodies against infliximab were detected in 61 percent of patients. The presence of concentrations of 8.0 microg per milliliter or greater before an infusion predicted a shorter duration of response (35 days, as compared with 71 days among patients with concentrations of less than 8.0 microg per milliliter; P<0.001) and a higher risk of infusion reactions (relative risk, 2.40; 95 percent confidence interval, 1.65 to 3.66; P<0.001). Infliximab concentrations were significantly lower at four weeks among patients who had had an infusion reaction than among patients who had never had an infusion reaction (median, 1.2 vs. 14.1 microg per milliliter; P<0.001). Patients who had infusion reactions had a median duration of clinical response of 38.5 days, as compared with 65 days among patients who did not have an infusion reaction (P<0.001). Concomitant immunosuppressive therapy was predictive of low titers of antibodies against infliximab (P<0.001) and high concentrations of infliximab four weeks after an infusion (P<0.001). CONCLUSIONS: The development of antibodies against infliximab is associated with an increased risk of infusion reactions and a reduced duration of response to treatment. Concomitant immunosuppressive therapy reduces the magnitude of the immunogenic response