New life in a sleeper: thalidomide and Crohn's disease

Thalidomide and thalidomide analogues for induction of remission in Crohn's disease

BACKGROUND

Crohn's disease is a chronic relapsing condition of the alimentary tract with a high morbidity secondary to bowel inflammation. High levels of tumour necrosis factor-alpha (TNF-alpha) have been associated with the development of intestinal inflammation in Crohn's disease.Thalidomide, has been demonstrated to have anti TNF-alpha properties in experimental and clinical studies.

OBJECTIVES

To evaluate the efficacy and safety of thalidomide and its analogue lenalidomide for induction of remission in Crohn's disease.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL) Issue 3, 2008, PUBMED (1966 to August 2008), EMBASE (1984 to August 2008) and the Cochrane IBD/FBD Specialised Trial Register were searched. Manufacturers of thalidomide and leaders in the field were also contacted to identify any unpublished trials. Study references were also searched for additional trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared thalidomide or lenalidomide against placebo or any other intervention for induction of remission in Crohn's disease were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of methodological quality of included studies were independently performed by two authors. The main outcome measure was clinical remission. Odds ratios and 95% confidence intervals were calculated for dichotomous outcomes.

MAIN RESULTS

No published RCTs on thalidomide for induction of remission in Crohn's disease were found. One RCT in paediatric patients is in progress. One RCT using lenalidomide (n = 89) met the inclusion criteria and was included in the review. Three parallel groups of patients on 25 mg of lenalidomide daily (n = 23) , 5 mg of lenalidomide daily (n = 33) or placebo (n = 28) were studied. The clinical remission rate in both treatment groups was not significantly different from that in the placebo group; 25 mg lenalidomide versus placebo (OR 0.29; 95% CI 0.05 to 1.54), 5 mg lenalidomide versus placebo (OR 1.30; 95% CI 0.42 to 4.05). There were no statistically significant differences in clinical response.

AUTHORS' CONCLUSIONS

The results of one well designed study using lenalidomide did not show any statistically significant benefit over placebo. The use of thalidomide or lenalidomide for induction of remission in Crohn's disease is not recommended until data from a definitive study are available.

Thalidomide and thalidomide analogues for maintenance of remission in Crohn's disease

BACKGROUND

Maintenance of remission is a major issue in the management of Crohn's disease. Thalidomide, a tumour necrosis factor-alpha (TNF-alpha) inhibitor and its analogue, lenalidomide, may have a role in the management of Crohn's disease, but it is not clear whether it is an effective maintenance therapy.

OBJECTIVES

To conduct a systematic review to evaluate the efficacy and safety of thalidomide and lenalidomide for the maintenance of remission in Crohn's disease.

SEARCH STRATEGY

MEDLINE (1966 to September 2008), EMBASE (1984 to September 2008), the Cochrane Central Register of Controlled Trials from the Cochrane Library (Issue 3, 2008) and the IBD/FBD Review Group Specialized Trials Register were searched to identify relevant studies.

SELECTION CRITERIA

Randomised controlled trials which compared thalidomide with either placebo or an active comparator were considered for inclusion.

DATA COLLECTION AND ANALYSIS

No trials met the inclusion criteria.

MAIN RESULTS

No studies that satisfied the inclusion criteria were found. In the absence of any suitable randomised controlled trial in this area, no analysis was performed.

AUTHORS' CONCLUSIONS

There is no evidence to support or refute the use of thalidomide or its analogue, lenalidomide, as maintenance therapy for patients with Crohn's disease. Given the teratogenic nature of thalidomide its use for maintenance therapy is difficult to justify. Well designed clinical trials are needed to evaluate the efficacy and safety of lenalidomide in Crohn's disease and its use is not recommended until these data are available.

Allyl isothiocyanate (AITC) and phenyl isothiocyanate (PITC) inhibit tumour-specific angiogenesis by downregulating nitric oxide (NO) and tumour necrosis factor-alpha (TNF-alpha) production

Angiogenesis, a crucial step in the growth and metastasis of cancers, is initiated with vasodilation mediated by nitric oxide (NO). The pro-inflammatory cytokine, tumour necrosis factor-alpha (TNF-alpha), is a mediator of nitric oxide synthesis. We analyzed the effect of allyl isothiocyanate (AITC) and phenyl isothiocyanate (PITC) on serum NO as well as TNF-alpha level during angiogenesis. In vivo antiangiogenic activity was studied using B16F-10 melanoma cell-induced capillary formation in C57BL/6 mice. Intraperitoneal administration of AITC and PITC at a concentration of 25 microg/dose/animal significantly inhibited tumour-directed capillary formation. Treatment of AITC and PITC significantly downregulated serum NO as well as TNF-alpha level in angiogenesis-induced animals compared to untreated control animals. The in vitro antiangiogenic study, using rat aortic ring assay, showed that both AITC and PITC at non-toxic concentrations inhibited the production of proangiogenic factors from B16F-10 melanoma cells which was evident with the inhibition of microvessel outgrowth from aortic rings. Both AITC and PITC significantly inhibited sodium nitroprusside as well as TNF-alpha-induced microvessel outgrowth from rat aortic ring. Administration of AITC and PITC also significantly reduced NO and TNF-alpha production by LPS-stimulated macrophages both in vivo as well as in vitro. Bio-assay using serum of angiogenesis-induced animals and supernatant from LPS-stimulated macrophages clearly confirmed the downregulatory action of AITC and PITC on TNF-alpha production. These results clearly demonstrated that AITC and PITC inhibited tumour-specific angiogenesis by downregulating NO and TNF-alpha production.

Recent developments in the pharmacological treatment of Crohn’s disease

Therapy for Crohn's disease (CD) is rapidly evolving with the emergence of new discoveries in disease pathogenesis. Since the approval of the first biological agent, infliximab, there have been several others that have been studied and are available for use within the context of clinical trials, in CD patients who do not respond to conventional medications or whose disease cannot be maintained in remission with the use of infliximab. The number of available drugs that have focused on the inhibition of TNF is growing. To avoid the injectable route of administering biologicals, several oral agents, such as thalidomide analogues, nonabsorbable antibiotics, such as rifaximin, and specific antibiotics, such as ornidazole, are being studied and considered for patients with CD. Hormonal therapies, such as growth hormone, coherin, medroxyprogesterone acetate and dehydroepiandrosterone, are other novel therapies for CD. Immunomodulators in use in other fields of medicine, including tacrolimus, 6-thioguanine and leflunomide, are being evaluated for the treatment of patients with CD and are also discussed. Several other promising therapies, such as cyclophosphamide, extracorporeal photochemotherapy, stem cell transplantation and the use of porcine whipworm, add to the available therapeutic armamentarium of this life-long remitting and relapsing disease. The future for CD patients is promising with the ever-expanding repertoire of drugs that are being studied.

Thalidomide for the treatment of recalcitrant oral Crohn's disease and orofacial granulomatosis

It has been suggested that thalidomide may be effective in the management of Crohn's disease, including the associated oral lesions. We detail the clinical response to low-dose thalidomide of 5 patients with clinical features of orofacial granulomatosis or oral Crohn's disease recalcitrant to recognized immunosuppressant therapy. All patients had clinical resolution of their symptoms and signs. Transient somnolence was the only reported adverse effect. Remission was maintained by extending the period between thalidomide doses. Thalidomide should be considered an effective therapy for the short-term treatment of severe orofacial granulomatosis in appropriately counseled patients.

Generating hypotheses by discovering implicit associations in the literature: a case report of a search for new potential therapeutic uses for thalidomide

The availability of scientific bibliographies through online databases provides a rich source of information for scientists to support their research. However, the risk of this pervasive availability is that an individual researcher may fail to find relevant information that is outside the direct scope of interest. Following Swanson's ABC model of disjoint but complementary structures in the biomedical literature, we have developed a discovery support tool to systematically analyze the scientific literature in order to generate novel and plausible hypotheses. In this case report, we employ the system to find potentially new target diseases for the drug thalidomide. We find solid bibliographic evidence suggesting that thalidomide might be useful for treating acute pancreatitis, chronic hepatitis C, Helicobacter pylori-induced gastritis, and myasthenia gravis. However, experimental and clinical evaluation is needed to validate these hypotheses and to assess the trade-off between therapeutic benefits and toxicities.

Recent developments in inflammatory bowel disease

The evolving medical armamentarium holds promise for more precise and effective therapies for IBD. The experience with anti-TNF therapy, particularly infliximab, illustrates the potential efficacy of therapies targeted at specific mediators or pathways involved in the pathogenesis. Advances in molecular technology have enabled the development of novel and potentially effective targeted therapies. Equally important is the increasing scientific understanding of the pathogenesis of IBD, which will likely improve the ability to stratify disease and to select therapies based on genotypic, immunologic, and phenotypic profiles in the future.

New developments in the treatment of inflammatory bowel disease

Therapy of inflammatory bowel disease (IBD) is rapidly changing with the advent of new discoveries in disease pathogenesis. The need for targeted therapies against the uncontrolled immuno-inflammatory reaction in IBD together with a prerequisite for minimal side effects is driving improvement in old medicines and is leading to the development of new drugs. This review introduces emerging changes in IBD treatment, such as improvements in conventional IBD medications or their use. Balsalazide, budesonide and changes in the use of 5-aminosalicylate (5-ASA) products and purine analogues, such as azathioprine, are discussed. Additionally, studies examining the role of drugs newly introduced into IBD therapy, such as mycophenolate mofetil (MMF), thalidomide and heparin, are stated. Emerging biological therapies, such as therapies against TNF, therapies to enhance anti-inflammatory cytokines, therapeutic manoeuvres to disrupt immune cell trafficking, anti-oxidant therapies, as well as non-conventional treatments, such as diet therapies, prebiotics and probiotics, and helminth therapies are discussed.

Theoretical basis for the activity of thalidomide

The revival of thalidomide began shortly after the drug was withdrawn from the market because of its teratogenic properties. Therapeutic effects of thalidomide were found accidentally in leprosy patients with erythema nodosum leprosum (ENL). Subsequent research widened the understanding of the activity of thalidomide, and with improved methodology and the augmented background knowledge of immunology it was possible to interpret the properties of thalidomide more coherently. Effects on tumour necrosis factor-alpha (TNFalpha) release play an important role in the ability of thalidomide to affect the immune system. Alteration of synthesis and release of cytokines such as interleukin (IL)-1, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12 and interferon-gamma is involved in the complex mechanisms of thalidomide. Thalidomide targets leucocytes, endothelial cells and keratinocytes, affecting them in a different manner and at different cellular levels. Changes in the density of adhesion molecules alter leucocyte extravasation and the inflammatory response in the tissue involved. Several mechanisms for the teratogenic action of thalidomide are currently under review, but this mode of action of the drug still remains unclear and we review evidence-based hypotheses for the teratogenicity of thalidomide. Thalidomide shows significant clinical impact in several diseases such as ENL in lepromatous leprosy, chronic graft-versus-host disease, systemic lupus erythematosus, sarcoidosis, aphthous lesions in HIV infection, wasting syndrome in chronic illness, inflammatory bowel disease, multiple myeloma and some solid tumours. In 1998 the US Food and Drug Administration approved thalidomide exclusively for the treatment of ENL, and strict conditions were stipulated for its use in order to prevent teratogenic adverse effects. However, despite the promising findings of thalidomide at the molecular level, namely its anti-TNFalpha properties and its intercalation with DNA, and activity in clinical trials, there is still a great need for more intensive research.

Thalidomide treatment for refractory Crohn's disease: a review of the history, pharmacological mechanisms and clinical literature

Several recent case reports and clinical trials have demonstrated that thalidomide is emerging as an efficacious alternative in the treatment of selected patients with refractory Crohn's disease. The effects of thalidomide are at least partly mediated by down-regulation of tumour necrosis factor (TNF)-alpha, a potent proinflammatory cytokine. However, thalidomide is also known to inhibit angiogenesis, and it has several other well-described immunomodulatory properties. Clinical studies have confirmed that previously refractory Crohn's disease patients respond to thalidomide, and many enter clinical remission. Efficacy usually occurs within 4 weeks. Thalidomide also has steroid-sparing properties, and it is particularly useful in treating oral and fistulous complications of Crohn's disease. Although it is usually tolerable, careful monitoring is recommended to prevent toxicities, such as birth defects and peripheral neuropathy. This review provides a detailed summary of the literature to date on the use of thalidomide treatment for Crohn's disease. Special attention is directed towards its history, mechanisms, and proposed role. The recent development of thalidomide analogues is also discussed briefly.

The treatment of advanced renal cell cancer with high-dose oral thalidomide

Thalidomide is reported to suppress levels of several cytokines, angiogenic and growth factors including TNF-alpha, basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6). The resulting anti-angiogenic, immunomodulatory and growth suppressive effects form the rationale for investigating thalidomide in the treatment of malignancies. We have evaluated the use of high-dose oral thalidomide (600 mg daily) in patients with renal carcinoma. 25 patients (all men; median age, 51 years; range 34-76 years) with advanced measurable renal carcinoma, who had either progressed on or were not suitable for immunotherapy, received thalidomide in an escalating schedule up to a maximum dose of 600 mg daily. Treatment continued until disease progression or unacceptable toxicity were encountered. 22 patients were assessable for response. 2 patients showed partial responses (9%; 95% CI: 1-29), 7 (32%; 95% CI: 14-55) had stable disease for more than 6 months and a further 5 (23%; 95% CI: 8-45) had stable disease for between 3 and 6 months. We also measured levels of TNF-alpha, bFGF, VEGF, IL-6 and IL-12 before and during treatment. In patients with SD > or = 3 months or an objective response, a statistically significant decrease in serum TNF-alpha levels was demonstrated (P = 0.05). The commonest toxicities were lethargy (> or = grade II, 10 patients), constipation (> or = grade II, 11 patients) and neuropathy (> or = grade II, 5 patients). Toxicities were of sufficient clinical significance for use of a lower and well tolerated dose of 400 mg in currently accruing studies.

Integrating anti-tumor necrosis factor therapy in inflammatory bowel disease: current and future perspectives

Crohn's disease and ulcerative colitis are two idiopathic inflammatory disorders of the GI tract. Manifestations of disease can be severe and lead to long term therapy with a variety of medications and/or surgery. Standard medical therapy consists of agents that either treat suppurative complications or modulate the inflammatory cascade in a nonspecific manner. Many specific chemokine and cytokine effectors that promote intestinal inflammation have been identified. Such work has led to experimental clinical trials with a variety of cytokine antagonists. Compounds directed against one such cytokine, tumor necrosis factor alpha (TNF), have demonstrated the greatest clinical efficacy to date. This is consistent with scientific observations that suggest a central role for TNF in the inflammatory cascade. Infliximab is a chimeric monoclonal antibody against TNF that has been demonstrated to be effective for the treatment of Crohn's disease. Infliximab is Food and Drug Administration approved for the treatment of Crohn's disease. There exist several other TNF antagonists in various phases of investigation, including the monoclonal antibody CDP 571, the fusion peptide etanercept, the phosphodiesterase inhibitor oxpentifylline, and thalidomide. The clinical efficacy of these agents and the role of TNF in the pathogenesis of inflammatory bowel disease is reviewed.

Evolving treatment strategies for inflammatory bowel disease

Crohn's disease and ulcerative colitis are idiopathic inflammatory bowel diseases characterized by dysregulated intestinal immune responses in genetically susceptible hosts. Conventional approaches to the medical therapy of ulcerative colitis and Crohn's disease can now be directed at either induction or maintenance of remission to improve therapeutic efficacy while minimizing complications. Newer approaches have expanded the utility of conventional therapies by improving both safety and efficacy and highlight the importance of specific targets along the immunoinflammatory pathways. The combination of conventional and novel approaches now offers the potential of modifying the natural history of these diseases.

Manipulation of cytokines in the management of patients with inflammatory bowel disease

In recent years, new concepts have been formulated for the therapeutic management of the intractable forms of Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease. These advances are based largely on new insights into the immune-inflammatory events occurring in the gut of these patients. Analysis of the types of immune response ongoing in the inflamed intestine has revealed that in Crohn's disease there is predominantly a T-helper cell type 1 response, with exaggerated production of interleukin (IL)-12 and interferon (IFN)-gamma, whereas in ulcerative colitis the lesion seems more of an antibody-mediated hypersensitivity reaction. Despite these differences, downstream inflammatory events are the same in both conditions. In both Crohn's disease and ulcerative colitis mucosa, IL-1gamma, IL-6, IL-8 and tumour necrosis factor (TNF)-alpha are produced in excess, and the production of free radicals accompanying the influx of nonspecific inflammatory cells into the mucosa is above the normal range. Strategies aimed at inhibiting T-cell responses are therefore more relevant in Crohn's disease, whereas, in theory at least, inhibition of downstream inflammatory processes should be therapeutic in both Crohn's disease and ulcerative colitis. This review seeks to summarize studies in which anticytokine antibodies, cytokines or cytokine-modifying agents have been used in the treatment of either Crohn's disease or ulcerative colitis.

Advances in inflammatory bowel disease

Optimal management of patients with IBD requires a multidisciplinary approach involving primary care physicians, gastroenterologists, surgeons, radiologists, and nutritionists. The rapidly evolving medical armamentarium promises better quality of life for patients afflicted with these complex, chronic diseases. It is expected that future development of biologic agents will add to the therapeutic options, although it may complicate treatment algorithms. Surgical advancements, particularly in ileoanal anastomosis and bowel preservation by strictureplasty, have improved outcome dramatically. The focus on development of new therapies and refinement of older ones demands a constant attention to the latest peer-reviewed literature and that the clinician keep abreast of the various advancements that have been summarized here.