Tuberculous tonsillitis in a patient receiving etanercept treatment

A comprehensive review and evaluation of the side effects of the tumor necrosis factor alpha blockers etanercept, infliximab and adalimumab

For more than 5 years, infliximab and etanercept have been utilized to treat rheumatoid arthritis and Crohn's disease. There is therefore much post-approval data on their side effects. A variety of Medline searches were done at the beginning of June 2004 using the terms 'etanercept', 'infliximab' and 'adalimumab' and the words 'lymphoma', 'infection', 'congestive heart failure', 'demyelinating disease', 'lupus', 'antibodies', 'injection site reaction', 'systemic', 'side effects' and 'skin'. Approximately 150 articles were so identified. In addition, FDA and manufacturers' data obtained by internet searches using Google were reviewed. The important side effects that have been most extensively related to TNFalpha blockers include: lymphoma, infections, congestive heart failure, demyelinating disease, a lupus-like syndrome, induction of auto-antibodies, injection site reactions, and systemic side effects. The risk of these side effects is very low. Nevertheless, it is important for clinicians to be aware of these side effects when prescribing therapy.

Hereditary auto-inflammatory disorders and biologics

The term auto-inflammatory disorders has been coined to describe a group of conditions characterized by spontaneously relapsing and remitting bouts of systemic inflammation without apparent involvement of antigen-specific T cells or significant production of auto-antibodies. The hereditary periodic fever syndromes are considered as the prototypic auto-inflammatory diseases, and genetic studies have yielded important new insights into innate immunity. DNA analysis has greatly enhanced the clinical characterization of these conditions, and elucidation of their molecular aetiopathogenesis has suggested that therapies may be aimed at specific targets within the immune cascade. The availability of biologic response modifiers such as inhibitors of tumour necrosis factor (TNF) and interleukin-1beta has greatly improved the outlook for some of these disorders, although effective therapies remain elusive in patients with certain conditions, including hyperimmunoglobulinaemia-D with periodic fever syndrome (HIDS) and a proportion of those with TNF-receptor associated periodic syndrome (TRAPS). Indeed, outstanding challenges and the unique potential to further elucidate molecular mechanisms in innate immunity are illustrated by the dashed early hope that TNF blockade would be a panacea for TRAPS: not only is etanercept (Enbrel) ineffective in some cases, but there are anecdotal reports of this condition being greatly exacerbated by infliximab (Remicade).

Infections associated with tumor necrosis factor-alpha antagonists

Tumor necrosis factor-alpha (TNF-alpha) is a proinflammatory cytokine involved in a wide range of important physiologic processes. This cytokine has a pathologic role in some diseases, and TNF-alpha antagonists are effective in treating inflammatory conditions. Given the putative role of TNF-alpha in host defense against tuberculosis and other infections, the risk of infection with TNF-alpha antagonists is a concern. Therefore, we searched the literature for reports of tuberculosis and other infections associated with TNF-alpha-antagonist therapy. Although tuberculosis was rarely reported in randomized clinical comparisons of these antagonists, case reports and submissions to the MedWatch program of the United States Food and Drug Administration have been numerous. Most instances were associated with infliximab, but etanercept and adalimumab may also be associated with an increased risk of tuberculosis. Histoplasmosis, listeriosis, aspergillosis, coccidioidomycosis, and candidiasis have been associated with TNF-alpha antagonists, but the causative relationship is not clear. Potential recipients of these drugs should be rigorously screened with skin testing, detailed questioning about recent travel and potential tuberculosis exposure, assessment for symptoms such as cough and weight loss, and chest radiography to minimize their risk of acquiring or reactivating tuberculosis. As with other immunosuppressant drugs, TNF-alpha antagonists should not be given to patients with active infection.

Etanercept

Etanercept (Enbrel, Wyeth Pharmaceuticals) is a fusion protein composed of a soluble TNF alpha receptor issued from bio-technology. It is a member of TNF alpha's family with two others marked infliximab (Remicade, Scheringh Plough Laboratory), chimeric monoclonal antibody (25 p. 100 mouse) and adalimumab (Humira, Abbott France Laboratory), humanized monoclonal antibody (100 p. 100 human). In United States, etanercept is approved by Food and Drug Administration, since 1998, to treat rheumatoid arthritis showing an inadequate response to prior therapy with other disease-modifying antirheumatic drugs (DMARDS). In France, the MA (Marketing Authorization) is more recent, in 2000, etanercept to treat active rheumatoid arthritis who showed an inadequate response to others DMARDS (like methotrexate for example), with opportunity, in 2002, to administer etanercept in active, severe RA, in first line treatment without previous use of methotrexate. Others MA have been obtained in ankylosing spondylitis (2004) polyarticular-course juvenile rheumatoid arthritis (2000), and in the treatment of psoriasic arthritis (2002). Request of MA have been realised to treat cutaneous mild to severe psoriasis in adult, which failed to respond, contradication or no tolerance with systemic treatment as methotrexate, cyclosporine or phototherapy. Among the others anti-TNF therapy, only infliximab can be prescribed, in dermatology, to treat psoriatic arthritis in France. Encouraging good results were the subject of cases report, but lacking clinical trial, predicting probably administration of etanercept in others indications in future. TNF alpha is a proinflammatory cytokine and plays an important role in the physiopathology of large inflammatory diseases. Logically, in future, we should increased prescription of biotherapy, particularly anti-TNF alpha. We have to mind short or mild-term adverse events, widely described in the literature, but long-term side effects remained unknown. Moreover, these biotherapic agents have a high cost and should be estimate.

Mycobacterium abscessus infection after use of tumor necrosis factor α inhibitor therapy: case report and review of infectious complications associated with tumor necrosis factor α inhibitor use

Tumor necrosis factor alpha (TNF-alpha) inhibitors, such as infliximab and etanercept, are now frequently used in the treatment of inflammatory diseases including rheumatoid arthritis (RA) and Crohn's disease. As an apparent result of their immune modulating activity, there has been an observed association between the use of these agents and the development of a wide range of infections, most notably Mycobacterium tuberculosis. We describe a case of infection with Mycobacterium abscessus in a 67-year-old woman receiving infliximab as a component of her therapy for RA. This case, along with extensive reports in the medical literature, illustrate how treatment with inhibitors of TNF-alpha has the potential to result in a wide range of infectious complications, including rapid growing Mycobacterium.

Infections associated with tumor necrosis factor-alpha antagonists

Tumor necrosis factor (TNF)-alpha antagonists are promising therapeutic agents for patients with severe autoimmune and rheumatologic conditions. Unfortunately, their use has been associated with an increased rate of tuberculosis, endemic mycoses, and intracellular bacterial infections. Infliximab, 1 of 3 available drugs in this novel class, appears to be associated with the greatest risk of infection, likely because of its long half-life and induction of monocyte apoptosis. Prospective trials are necessary to determine the exact risk associated with these agents, particularly the newer TNF-alpha antagonists. More specific TNF-alpha blockers, which reduce inflammation while maintaining adequate immunity, are needed. In the meantime, a thorough work-up is mandatory for all febrile illness occurring in TNF-alpha blocker recipients. We present 4 patients who developed severe infections during TNF-alpha antagonist therapy, review the literature, and discuss current guidelines for surveillance and prophylaxis.

Blockade of TNF does not alter oxygen burst and phagocytosis of human neutrophils in patients with rheumatoid arthritis

Clinical trials evaluating tumor necrosis factor alpha (TNF-alpha) binding agents in patients with rheumatoid arthritis (RA) have demonstrated significant efficacy in reducing symptoms of disease and slowing radiographic progression. However, infectious complications are the most severe and common adverse effects of anti-TNF therapy. The functional capacities of neutrophils (PMNs) as the first line of defense in bacterial and fungal infections are enhanced by soluble TNF as a potent neutrophil primer. The aim of this study was to assess the influence of in vivo TNF blockade on oxygen burst (OB) and phagocytosis of human neutrophils. PMNs were derived from 20 patients with RA on anti-TNF-alpha therapy and 13 patients using conventional DMARDs. By flow cytometry we measured OB upon stimulation with Escherichia coli and N-formyl-1-methionyl-1-leucyl-phenylalanine (FMLP) with and without priming with granulocyte-colony stimulating factor (G-CSF) and/or TNF-alpha using dihydrorhodamine (DHR) 123. Phagocytosis of fluorescein isothiocyanate (FITC)-labeled E. coli was also assessed by flow cytometry. Thirty-three healthy volunteers served as controls. Upon stimulation with E. coli and FMLP, there was no significant difference in OB between the two patient groups and healthy controls. Priming was effective in all groups. Phagocytosis of E. coli by PMNs was equally effective in controls and patients independent from the treatment regimen. These data show that OB, phagocytosis and responsiveness to priming with TNF and G-CSF of PMNs are not impaired in patients with RA treated with anti-TNF agents in comparison with patients on conventional DMARDs or healthy controls. Thus, the infectious complications observed in patients with TNF blockade cannot be explained by functional impairment of PMNs; however, the neutralization of TNF as a potent primer of neutrophil response may increase the susceptibility for infections in these patients.

Serious infections associated with anticytokine therapies in the rheumatic diseases

The ability to target and neutralize macrophage-derived inflammatory cytokines, particularly tumor necrosis factor-alpha (TNF-alpha), has emerged in recent years as one of the most important advances in the treatment of rheumatoid arthritis, Crohn's disease, and several other systemic inflammatory diseases. In rheumatoid arthritis, for example, these biological agents rapidly reduce signs and symptoms of joint inflammation and profoundly slow the progression of joint damage. However, data that have emerged following Food and Drug Administration approval of these agents have alerted clinicians to an increased likelihood of opportunistic infections in patients treated with these agents, particularly tuberculosis. The effect of TNF inhibition on the frequency of infection with more common bacterial pathogens is less clear. Animal models of tuberculosis and other opportunistic infections have demonstrated the importance of TNF-alpha in controlling and containing intracellular pathogens. The spectrum of infections reported to date in the setting of anti-TNF-alpha treatment is reviewed here. In addition, relevant animal data illustrating potential mechanistic roles for TNF-alpha in host responses to infection are also reviewed.

Anti-tumour necrosis factor alpha therapy in rheumatoid arthritis: an update on safety

Anti-TNFalpha therapy may have associated risks of serious infection, congestive heart failure, malignancy, and multiple sclerosis. The magnitude of these risks is difficult to assess. This article reviews publications on the current knowledge about the safety of these agents.