Tumor Necrosis Factor Receptor Fusion Research Articles

Magnetic resonance imaging examinations of the spine in patients with ankylosing spondylitis before and after therapy with the tumor necrosis factor α receptor fusion protein etanercept

To assess spinal inflammation by magnetic resonance imaging (MRI) before and after treatment with the tumor necrosis factor receptor fusion protein etanercept compared with placebo. As part of a recently published randomized, controlled trial, 40 patients with ankylosing spondylitis (AS) underwent MRI of the lower thoracic and lumbar spine at 4 different time points: baseline, 12 weeks, 24 weeks, and 48 weeks. Nineteen patients received subcutaneous etanercept twice weekly (25 mg twice daily) for 1 year, and 21 patients received placebo for 6 months before being switched to etanercept. The mean age of the patients was 39.7 years, 75% were male, 89% were HLA-B27 positive, and the mean disease duration was 13 years. MRI examinations included T1-weighted sequences before and after application of gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) and T2-weighted fat-saturated sequences. MRI sequences were scored with an adjusted AS spinal MRI score, using predefined vertebral units (VUs) as a basis. After 12 weeks, spinal inflammation (as assessed by T2-weighted MRI with fat saturation) regressed by 54% in the etanercept group (mean score 1.33 per VU at baseline and 0.61 per VU at 12 weeks; P = 0.002) but worsened by 13% in the placebo group (0.94 at baseline and 1.06 at 12 weeks) (P < 0.001 between groups). After switching to etanercept, placebo patients improved similarly. T1-weighted Gd-DTPA MRI sequences performed equally well in detecting spinal changes. At baseline, >50% of all active lesions were detected in the thoracic spine. Deterioration of chronic changes was significant only in patients treated with placebo. Etanercept treatment of patients with active AS results in regression of spinal inflammation as assessed by spinal MRI. Inclusion of the thoracic spine in MRI examinations of patients with AS may be of particular importance.

Gene transfer of tumor necrosis factor inhibitor improves the function of lung allografts

Background Tumor necrosis factor is an important mediator of lung transplant acute rejection. Soluble type I tumor necrosis factor receptor binds to tumor necrosis factor-α and -β and inhibits their function. The objectives of this study were to demonstrate efficient in vivo gene transfer of a soluble type I tumor necrosis factor receptor fusion protein (sTNF-RI-Ig) and determine its effects on lung allograft acute rejection. Methods Three groups of Fischer rats (n = 6 per group) underwent recipient intramuscular transfection 24 hours before transplantation with saline, 1 × 10 10 plaque-forming units of control adenovirus encoding β-galactosidase, or 1 × 10 10 plaque-forming units of adenovirus encoding human sTNF-RI-Ig (Ad.sTNF-RI-Ig). One group (n = 6) received recipient intramuscular transfection with 1 × 10 10 Ad.sTNF-RI-Ig at the time of transplantation. Brown Norway donor lung grafts were stored for 5 hours before orthotopic lung transplantation. Graft function and rejection scores were assessed 5 days after transplantation. Time-dependent transgene expression in muscle, serum, and lung grafts were evaluated by using enzyme-linked immunosorbent assay of human soluble type I tumor necrosis factor receptor. Results Recipient intramuscular transfection with 1 × 10 10 plaque-forming units of Ad.sTNF-RI-Ig significantly improved arterial oxygenation when delivered 24 hours before transplantation compared with saline, β-galactosidase, and Ad.sTNF-RI-Ig transfection at the time of transplantation (435.8 ± 106.6 mm Hg vs 142.3 ± 146.3 mm Hg, 177.4 ± 153.7 mm Hg, and 237.3 ± 185.2 mm Hg; P = .002, .005, and .046, respectively). Transgene expression was time dependent, and there was a trend toward lower vascular rejection scores ( P = .066) in the Ad.sTNF-RI-Ig group transfected 24 hours before transplantation. Conclusions Recipient intramuscular Ad.sTNF-RI-Ig gene transfer improves allograft function in a well-established model of acute rejection. Maximum benefit was observed when transfection occurred 24 hours before transplantation.

Absence of a pharmacokinetic interaction between etanercept and warfarin.

Etanercept, a soluble recombinant human tumor necrosis factor receptor (TNFr) fusion protein, is effective and well tolerated in the treatment of rheumatoid arthritis (RA), juvenile rheumatoid arthritis (JRA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS). The primary objective of this study was to investigate the potential pharmacokinetic and pharmacodynamic interaction between a single dose of R- and S-enantiomers of warfarin and multiple doses of etanercept after administration of warfarin and etanercept alone and together. In a nonrandomized, three-period study, 12 healthy male subjects received a single oral 25-mg dose of warfarin after an overnight fast, followed by twice-weekly 25-mg subcutaneous doses of etanercept for seven doses. The last dose of etanercept was administered concurrently with a second dose of warfarin. Serial blood samples for plasma warfarin concentration measurement and international normalized ratio (INR) assessment were collected before and up to 144 hours after dose administration. Serial blood samples for serum etanercept concentration measurement were collected before and up to 60 hours after the sixth dose and 264 hours after the seventh dose. Etanercept did not affect the pharmacokinetics and pharmacodynamics of warfarin. All ratios of maximum serum concentration (C(max)) and area under the serum concentration versus time curve (AUC) for pharmacokinetics (R- and S-enantiomers of warfarin) and INR fell within the confidence interval of 0.8 to 1.25. Warfarin also did not cause a clinically significant alteration in the pharmacokinetics of etanercept. In conclusion, coadministration of etanercept and warfarin would not be expected to change the pharmacokinetics of either medication; therefore, no dosage adjustment is needed in cases in which warfarin and etanercept are coadministered.

Pilot study of recombinant human soluble tumor necrosis factor (TNF) receptor (p75) fusion protein (TNFR:Fc; Enbrel) in patients with refractory multiple myeloma: increase in plasma TNFα levels during treatment

Elevated tumor necrosis factor (TNF)-α levels are associated with poor prognosis in patients with multiple myeloma (MM). Enbrel is a TNF antagonist fusion protein consisting of the extracellular, ligand-binding domain of the human p75 TNF receptor linked to the Fc portion of human IgG1. Ten patients with refractory MM were treated with Enbrel 25 mg s.c twice weekly for a minimum of eight median age was 63 years (range, 43–76). The total number of Enbrel doses was 191 (median 16; range, 3–55). TNFα plasma levels increased significantly during treatment with Enbrel. No objective response occurred. Acceleration of disease occurred in four patients. While well-tolerated, Enbrel did not have anti-myeloma activity as administered on this study.

Biologic therapy of inflammatory bowel disease

Advancing knowledge regarding the biology of chronic inflammation has led to the development of specific biologic therapies that mechanistically target individual inflammatory pathways. Many biologic therapies are being evaluated for the treatment of the chronic inflammatory bowel diseases, Crohn's disease and ulcerative colitis. Biologic compounds proven to be effective for Crohn's disease include monoclonal antibodies to tumor necrosis factor (infliximab and CDP571) and to the leukocyte adhesion molecule alpha4 integrin (natalizumab). Other biologic compounds for which there is insufficient evidence to judge efficacy for inflammatory bowel disease include: p55 tumor necrosis factor binding protein (onercept); interferon alpha; interferon beta-1a; anti-interferon gamma antibody; anti-interleukin 12 antibody; p65 anti-sense oligonucleotide (blocks NF-kappaB); granulocyte colony stimulating factor, and granulocyte macrophage colony stimulating factor; anti-interleukin 2 receptor antibody; epidermal growth factor; keratinocyte growth factor 2 (repifermin); human growth hormone; anti-CD4 antibody; and anti-alpha4beta7 antibody. Biologic therapies that have been proven ineffective for inflammatory bowel disease include: interleukin 10; interleukin 11; anti-sense intercellular adhesion molecule-1; and the tumor necrosis factor receptor fusion protein etanercept. Based on the early successes of infliximab, CDP571 and natalizumab, it seems certain that biologic therapy will play an important role in the future treatment of inflammatory bowel disease.

Exacerbation of mycobacterium tuberculosis enteritis masquerading as crohn’s disease after treatment with a tumor necrosis factor-α inhibitor

Infliximab (Remicade; Centocor, Inc, Malvern, Pennsylvania), a chimeric monoclonal antibody to tumor necrosis factor-α (TNF-α), and etanercept (Enbrel; Immunex Corporation, Seattle, Washington), a recombinant tumor necrosis factor receptor fusion protein, are new immunomodulating agents used in the treatment of patients with rheumatoid arthritis. Infliximab has also been approved for the management of moderate-to-severe Crohn’s disease. Both agents block the action of TNF-α, a cytokine that has proinflammatory effects and modulates the cellular immune response. Thus, TNF-α inhibition may increase the risk of infection. Postmarketing reports of adverse effects associated with infliximab and etanercept have prompted the Food and Drug Administration (FDA) to announce the risk of serious infections and sepsis associated with the use of these agents. We describe a patient who was treated with infliximab for what was thought to be Crohn’s disease, who became systemically ill with Mycobacterium tuberculosis enteritis.

Etanercept in the treatment of active refractory Crohn’s disease: a single-center pilot trial

OBJECTIVES: Etanercept, an injectable tumor necrosis factor (TNF) receptor fusion protein, binds and inactivates human TNF and is used in active rheumatoid arthritis. Blocking TNF with monoclonal antibodies has also been beneficial in Crohn’s disease. We attempted to determine the efficacy and safety of etanercept for induction of clinical, endoscopic, and histological improvement in patients with moderate to severe Crohn’s disease despite standard treatment. METHODS: Ten patients with active Crohn’s disease were treated with etanercept (25 mg s.c.) twice per week for 12 wk. Background therapy was kept stable during the trial. Crohn’s disease activity index (CDAI), Inflammatory Bowel Disease Questionnaire, and C-reactive protein levels were measured at weeks 0, 2, 4, 8, and 12. Colonoscopies were performed before and after therapy in responders; endoscopic biopsies were scored for inflammation. RESULTS: At week 2 after the start, a clinical response (ΔCDAI ≥ 70) was observed in 6/10 patients (median = 305 [294–418] to 166 [107–392]), with reduction in serum C-reactive protein levels (median = 17.2 [6.8–67.2] to 9.1 [0.9–17.2] mg/dl). Colonoscopies showed a reduction in inflammatory lesions in the four patients who attained remission (CDAI < 150), whereas the inflammatory score of the biopsies did not decrease significantly. No moderate or severe adverse events were observed. CONCLUSIONS: Etanercept may be effective in Crohn’s disease refractory to standard therapy.

Early diagnosis and treatment of rheumatoid arthritis for improved outcomes: Focus on etanercept, a new biologic response modifier

Early diagnosis and prompt treatment can improve outcomes in rheumatoid arthritis (RA). Significant joint damage occurs early in the course of the disease, when RA is most aggressive. Many rheumatologists now advocate an inverted pyramid approach to therapy, in which treatment with disease-modifying antirheumatic drugs is initiated on diagnosis. The goals of this approach are to preserve patient function and to slow disease progression. Current therapies exhibit varying degrees of efficacy and cumulative toxicity that frequently limit their usefulness, particularly with long-term use. New biologic response modifiers (BRMs) that target specific cells or cytokines involved in the inflammatory response hold great promise for RA therapy because of their improved efficacy and limited toxicity. The first BRM to be approved by the US Food and Drug Administration for use in RA is etanercept, a soluble tumor necrosis factor-receptor fusion protein. Etanercept is highly effective in relieving RA symptoms and has a good safety profile. The availability of welltolerated therapies may encourage clinicians to diagnose and treat RA more promptly, thereby ensuring patients the best possible outcomes.

SOLUBLE TUMOR NECROSIS FACTOR RECEPTOR (p75) FUSION PROTEIN (ENBREL) AS A THERAPY FOR RHEUMATOID ARTHRITIS

Soluble tumor necrosis factor (TNF) receptor fusion protein (p75) (Enbrel) is a reversible inhibitor of the biologic effects of TNF. Enbrel has been shown in placebo-controlled trials to significantly improve the signs and symptoms of rheumatoid arthritis. Clinical trials are now in progress to assess the safety and efficacy of Enbrel in combination with methotrexate in refractory rheumatoid arthritis along with trials to compare Enbrel to methotrexate in patients with early rheumatoid arthritis.

P55 Tumor Necrosis Factor Receptor Fusion Protein in the Treatment of Patients With Severe Sepsis and Septic Shock

To evaluate the safety and efficacy of p55 tumor necrosis factor receptor fusion protein, a recombinant chimeric protein of human p55 (type I) tumor necrosis factor receptor (CD120a) extracellular domain and IgG1 sequences (referred to as p55-IgG), in the treatment of patients with severe sepsis or septic shock.Randomized, prospective, multicenter, double-blind, placebo-controlled clinical trial.Forty-four community and university-affiliated hospitals in the United States and Europe.There were 498 patients enrolled in this clinical trial.Patients prospectively stratified within each site into refractory shock or severe sepsis groups were randomized to receive a single infusion of p55-IgG, 0.083 mg/kg, 0.042 mg/kg, or 0.008 mg/kg, or placebo. Patients received standard aggressive medical/surgical care during the 28-day postinfusion period.Twenty-eight-day all-cause mortality.The distribution of variables describing demographics, organ system dysfunction or failure, infecting microorganisms, predicted mortality, plasma interleukin 6 levels, and plasma tumor necrosis factor alpha (TNF-alpha) levels were similar among patients in the p55-IgG and placebo treatment arms. A planned interim analysis was performed after 201 patients were enrolled. Because a statistically nonsignificant trend toward increased mortality was present in patients who had received 0.008 mg/kg, this treatment arm was discontinued, and the study continued with 3 arms. Among all infused patients, there was a statistically nonsignificant trend toward reduced 28-day all-cause mortality in those who received p55-IgG compared with placebo-treated patients (5% reduction, 0.042 mg/kg vs placebo; 15% reduction, 0.083 mg/kg vs placebo; P=.30). However, in patients with severe sepsis and early septic shock (n=247), therapy with p55-IgG, 0.083 mg/kg, was associated with a 36% reduction in 28-day all-cause mortality compared with placebo (P=.07): 20 (23%) of 87 patients died among those treated with p55-IgG, 0.083 mg/kg; 30 (37%) of 82 among those treated with p55-IgG, 0.042 mg/kg; and 28 (36%) of 78 in the placebo group. A prospectively planned logistic regression analysis to assess treatment effect on 28-day all-cause mortality by means of predicted mortality and serum interleukin 6 levels as continuous covariates demonstrated a significant improvement in outcome for the patients with severe sepsis treated with p55-IgG, 0.083 mg/kg, compared with placebo (P=.01). Serious adverse events, including death and the development of new organ system dysfunction, were reported in 65% of patients infused with placebo, with no increased frequency (56%) present in the 2 p55-IgG treatment arms. There were no reports of immediate hypersensitivity reactions caused by p55-IgG.In this dose-finding study, there was no decrease in mortality between placebo and p55-IgG in all infused patients. In the prospectively defined population of patients with severe sepsis who received p55-IgG, 0.083 mg/kg, there was a trend toward reduced mortality at day 28 that became significant when predicted mortality and plasma interleukin 6 levels were included in a logistic regression analysis.

P55 Tumor necrosis factor receptor fusion protein in the treatment of patients with severe sepsis and septic shock. A randomized controlled multicenter trial. Ro 45-2081 Study Group

To evaluate the safety and efficacy of p55 tumor necrosis factor receptor fusion protein, a recombinant chimeric protein of human p55 (type I) tumor necrosis factor receptor (CD120a) extracellular domain and IgG1 sequences (referred to as p55-IgG), in the treatment of patients with severe sepsis or septic shock. Randomized, prospective, multicenter, double-blind, placebo-controlled clinical trial. Forty-four community and university-affiliated hospitals in the United States and Europe. There were 498 patients enrolled in this clinical trial. Patients prospectively stratified within each site into refractory shock or severe sepsis groups were randomized to receive a single infusion of p55-IgG, 0.083 mg/kg, 0.042 mg/kg, or 0.008 mg/kg, or placebo. Patients received standard aggressive medical/surgical care during the 28-day postinfusion period. Twenty-eight-day all-cause mortality. The distribution of variables describing demographics, organ system dysfunction or failure, infecting microorganisms, predicted mortality, plasma interleukin 6 levels, and plasma tumor necrosis factor alpha (TNF-alpha) levels were similar among patients in the p55-IgG and placebo treatment arms. A planned interim analysis was performed after 201 patients were enrolled. Because a statistically nonsignificant trend toward increased mortality was present in patients who had received 0.008 mg/kg, this treatment arm was discontinued, and the study continued with 3 arms. Among all infused patients, there was a statistically nonsignificant trend toward reduced 28-day all-cause mortality in those who received p55-IgG compared with placebo-treated patients (5% reduction, 0.042 mg/kg vs placebo; 15% reduction, 0.083 mg/kg vs placebo; P=.30). However, in patients with severe sepsis and early septic shock (n=247), therapy with p55-IgG, 0.083 mg/kg, was associated with a 36% reduction in 28-day all-cause mortality compared with placebo (P=.07): 20 (23%) of 87 patients died among those treated with p55-IgG, 0.083 mg/kg; 30 (37%) of 82 among those treated with p55-IgG, 0.042 mg/kg; and 28 (36%) of 78 in the placebo group. A prospectively planned logistic regression analysis to assess treatment effect on 28-day all-cause mortality by means of predicted mortality and serum interleukin 6 levels as continuous covariates demonstrated a significant improvement in outcome for the patients with severe sepsis treated with p55-IgG, 0.083 mg/kg, compared with placebo (P=.01). Serious adverse events, including death and the development of new organ system dysfunction, were reported in 65% of patients infused with placebo, with no increased frequency (56%) present in the 2 p55-IgG treatment arms. There were no reports of immediate hypersensitivity reactions caused by p55-IgG. In this dose-finding study, there was no decrease in mortality between placebo and p55-IgG in all infused patients. In the prospectively defined population of patients with severe sepsis who received p55-IgG, 0.083 mg/kg, there was a trend toward reduced mortality at day 28 that became significant when predicted mortality and plasma interleukin 6 levels were included in a logistic regression analysis.

Inhibition of Sephadex-induced lung injury in the rat by Ro 45-2081, a tumor necrosis factor receptor fusion protein.

Tumor necrosis factor (TNF) is an inflammatory cytokine produced by many cell types which may contribute to the pathophysiology of a variety of lung diseases. In this study we have used Ro 45-2081 (a soluble receptor composed of the human p55 TNF receptor and human heavy-chain immunoglobulin G) to explore the role of TNF in the acute inflammatory response in the rat lung to intravenous injection of Sephadex beads. The effects of Ro 45-2081 have also been compared with those of dexamethasone. At 24 and 72 h after Sephadex, there was a significant increase in the total number of leukocytes in bronchoalveolar lavage fluid (BALF). At 24 h, the number of neutrophils comprised around 50% of the total leukocyte number, decreasing to around 10% of total by 72 h. The eosinophil count was maintained at around 10% of the total leukocyte number. Pretreatment with either Ro 45-2081 [1 and 3 mg kg-1, intraperitoneally (i.p.)] or dexamethasone (0.1 and 0.3 mg kg-1, i.p.) inhibited the neutrophilia at 24 h after Sephadex, although Ro 45-2081 had no significant effect on total cell number. At 72 h after Sephadex, Ro 45-2081 (1 and 3 mg kg-1, i.p., daily) significantly reduced the neutrophil influx into BALF but had no inhibitory effect on eosinophil number. In contrast, dexamethasone (0.1 and 0.3 mg kg-1, i.p., daily) virtually abolished the infiltration of neutrophils and eosinophils into BALF. The lack of effect of Ro 45-2081 on eosinophil infiltration into the rat lung and the inhibition caused by dexamethasone suggest that factors other than TNF are involved in this part of the inflammatory response induced by Sephadex. However, the inhibitory effects of Ro 45-2081 show that TNF may play an important role in the recruitment of neutrophils into the lungs of Sephadex-treated rats.