Role of tumor necrosis factor-alpha inhibition with inflixiMAB in cancer therapy and hematopoietic stem cell transplantation

Fundamental concepts of protein therapeutics and spacing in oncology: an updated comprehensive review

Current treatment regimens in cancer cases cause significant side effects and cannot effectively eradicate the advanced disease. Hence, much effort has been expended over the past years to understand how cancer grows and responds to therapies. Meanwhile, proteins as a type of biopolymers have been under commercial development for over three decades and have been proven to improve the healthcare system as effective medicines for treating many types of progressive disease, such as cancer. Following approving the first recombinant protein therapeutics by FDA (Humulin), there have been a revolution for drawing attention toward protein-based therapeutics (PTs). Since then, the ability to tailor proteins with ideal pharmacokinetics has provided the pharmaceutical industry with an important noble path to discuss the clinical potential of proteins in oncology research. Unlike traditional chemotherapy molecules, PTs actively target cancerous cells by binding to their surface receptors and the other biomarkers particularly associated with tumorous or healthy tissue. This review analyzes the potential and limitations of protein therapeutics (PTs) in the treatment of cancer as well as highlighting the evolving strategies by addressing all possible factors, including pharmacology profile and targeted therapy approaches. This review provides a comprehensive overview of the current state of PTs in oncology, including their pharmacology profile, targeted therapy approaches, and prospects. The reviewed data show that several current and future challenges remain to make PTs a promising and effective anticancer drug, such as safety, immunogenicity, protein stability/degradation, and protein-adjuvant interactions.

Use of Infliximab, an Anti-Tumor Necrosis Alpha Antibody, for Inflammatory Dermatoses

Background:

Infliximab is a monoclonal antibody against tumor necrosis factor alpha currently approved by the U.S. FDA for the treatment of Crohn's disease and rheumatoid arthritis. Recently, a controlled trial reported its effectiveness for psoriasis.

Objective:

The object of our study was to evaluate the efficacy and safety of infliximab for inflammatory or autoimmune cutaneous disorders.

Methods:

A retrospective chart review was performed for patients who received infliximab at the University of Miami, Cedars Medical Center.

Results:

Patients with various disease, including panniculitis, pityriasis rubra pilaris, eosinophilic fasciitis, discoid lupus erythematosus, and necrobiosis lipoidica diabeticorum, received infliximab infusion at a dose of 5 mg/kg. All patients had refractory disease or adverse effects to previous therapy, which included cyclosporine, systemic steroids, azathioprin, clofazimine, mycophenolate mofetil, acitretin, UVB, and thalidomide. Six out of the seven patients improved after treatment.

Conclusions:

Infliximab was well tolerated in most patients and the majority benefited from the use of infliximab.

Evaluation of the physicochemical and functional stability of diluted REMSIMA® upon extended storage--A study compliant with NHS (UK) guidance

A newly licensed biosimilar product containing infliximab as the active pharmaceutical ingredient has recently been marketed under the brand name Remsima^®. We have evaluated the stability of Remsima^® diluted in sodium chloride solution and stored in polyolefin bags at 2–8 °C using a range of techniques to assess the physico-chemical and functional integrity of the drug over time. The methods and techniques employed are fully compliant with NHS (UK) guidance for evaluating the stability of biologicals, enabling the data to be used for the application of an extended shelf-life to Remsima products in the UK, when prepared under a Section 10 exemption or a Specials Licence. The results clearly demonstrate physico-chemical and functional stability of the drug over the 7 day period of the study, when prepared as described here under aseptic conditions in accordance with the Summary of manufacturers Product Characteristics.

Theory-based analysis of the anti-inflammatory effect of TNF inhibitors on rheumatoid arthritis

TNF inhibitors are used as therapeutic agents for rheumatoid arthritis (RA). Each has a different dosage regimen and it is thought that the differences among them have implications on efficacy. However, those differences have not been analyzed in a theoretical manner. In the present study, we tried to explain theoretically the differences. We theoretically analyzed the anti-inflammatory effect of infliximab (IFX), etanercept (ETN), and adalimumab (ADA) for RA by using a pharmacokinetic and pharmacodynamic model. Then, we simulated values for sequential changes of tender joint count (TJC) after repeated administrations of TNF inhibitors by using the model. The sequential changes of TJC obtained with our model were in good agreement with observed TJC ratio data, which was considered to show the validity of our analytical method. The following results were obtained: the onset of clinical response was fastest with IFX, the fluctuation of IFX was greater than that of the others, and the clinical response with ADA was as stable as that with ETN. The present model was useful to analyze theoretically the anti-rheumatic effect of TNF inhibitors. Our results showed that different dosage regimens have implications on the onset and fluctuation of clinical response.

Infliximab for the Treatment of Severe Steroid Refractory Acute Graft-versus-host Disease in Three Patients after Allogeneic Hematopoietic Transplantation

Acute graft-versus-host disease (aGVHD) is a serious complication of allogeneic peripheral blood stem cell transplantation (PBSCT). Patients with severe aGVHD not responding to treatment with steroids have a poor prognosis. We treated three patients with severe aGVHD refractory to steroids with infliximab. Patients (MDS 1, NHL 1, ALL 1) developed grade II-IV GVHD at a median of 13 days (range 9-17) after non-myeloablative PBSCT (HLA mismatched). All patients had received treatment with high-dose steroids for a median of 7 days (range 7-10) in addition to mycophenolate mofetil (MMF) (one). Infliximab was given in 3 weekly doses of 5 mg/kg. In one of three patients a partial resolution of diarrhea and minor improvement of skin were observed. One patient died with refractory GVHD. Infliximab is apparently an effective drug for the treatment of aGVHD, but can be more effective at doses of 5 mg/kg or higher and/or by administering it repeatedly every week.

The spectrum of noninfectious pulmonary complications following hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) is an established treatment for a variety of malignant and nonmalignant conditions. Pulmonary complications, infectious and noninfectious, are a major cause of morbidity and mortality in these patients. The recent advances in prophylaxis and treatment of infectious complications increased the significance of noninfectious pulmonary conditions. Acute lung injury due to diffuse alveolar hemorrhage or idiopathic pneumonia syndrome are the main acute complications, while bronchiolitis obliterans remains the most challenging pulmonary complications facing clinicians who are taking care of HSCT recipients. There are other noninfectious pulmonary complications following HSCT that are less frequent. This report provides a clinical update of the incidence, risk factors, pathogenesis, clinical characteristics and management of the main noninfectious pulmonary complications following HSCT.

Theory-based analysis of anti-inflammatory effect of infliximab on Crohn's disease and rheumatoid arthritis

In Japan, the recommended dosage regimens of infliximab (IFX) for treatment of rheumatoid arthritis (RA) and Crohn's disease (CD) are different. However, the differences have not been analyzed theoretically. In a previous study, we constructed a pharmacokinetic-pharmacodynamic model to investigate the effects of IFX for CD and found it useful to establish a rational dosage regimen of IFX for individual patients with CD. In the present study, we investigated whether the theory-based model could be used for cases of RA and also used it to evaluate the validity of the dosage regimen. The results obtained with our model were in good agreement with observed tender joint count (TJC) ratio data, which was considered to show the validity of our analysis. Thus, we concluded that the model could be used for patients with RA. Furthermore, a second administration of IFX given 2 weeks after the first infusion was important to achieve remission in the early stage of RA. We also compared the estimated pharmacodynamic parameters of RA with those of CD. The elimination rate constant of inflammation in RA was greater than that in CD, suggesting that the recovery from inflammation in RA is faster than that in CD, and indicating a reason for the difference in dosage between RA and CD. In conclusion, use of our model in light of the individual quantitative factor of tumor necrosis factor (TNF)-α allows establishment of IFX dosage regimens for individual patients.

Graft-vs-host disease after small bowel transplantation in children

PURPOSE

Graft-vs-host disease (GVHD) is a rare complication of transplantation of organs rich in immunocompetent cells. The goal of this study was to report the features of GVHD after small bowel transplantation (SBTx) in children.

METHODS

The study involved a retrospective review of patients undergoing SBTx between 1999 and 2009 who had GVHD.

RESULTS

Of 46 children receiving 52 intestinal grafts (2 liver-intestine and 3 multivisceral), 5 (10%) developed GVHD. Median age at transplant was 42 (19-204) months. Baseline immunosupression consisted of tacrolimus and steroids supplemented with thymoglobulin (n = 2) or basiliximab (n = 3) for induction. Median time between transplantation and GVHD was 47 (16-333) days. All patients had generalized rash, 2 had diarrhea, and 2 had respiratory symptoms. Other symptoms were glomerulonephritis (n = 1) and conjunctivitis (n = 1). Four developed severe hematologic disorders. The diagnosis was confirmed by skin biopsy in 4 patients and supported by chimerism studies in two. Colonoscopy and opthalmoscopic findings were also suggestive in one. Treatment consisted of steroids and decrease of tacrolimus, with partial response in four. Other immunosuppressants were used in refractory or recurrent cases. Three patients died within 4 months after diagnosis.

CONCLUSION

Graft-vs-host disease is a devastating complication of SBTx, with high mortality probably associated with severe immunologic dysregulation.

Infliximab for managing steroid-refractory acute graft-versus-host disease

Infliximab has demonstrated activity in the treatment of steroid-refractory acute graft-versus-host disease (aGVHD). We aimed to confirm the effectiveness of infliximab as a salvage therapy for steroid-refractory aGVHD. In a series of 52 patients, 71% of whom had grade III-IV aGVHD, only 15% achieved complete remission (CR) with the use of infliximab alone as salvage therapy. CR of aGVHD differed according to overall aGVHD grade at salvage (grade II, 5/15; grade III, 2/17; grade IV, 1/20; P=.03). Median overall survival (OS) was only 1.7 months (95% confidence interval [CI]=0.99 to 2.3 months). CR of aGVHD was significantly associated with OS, with a hazard ratio of 8.4 for death in those without CR (95% CI=3.6 to 19.6; P < .0001). This series demonstrates the limited activity of infliximab in patients with high-grade aGVHD. Further work is needed to identify effective therapy for aGVHD.

Separating graft-versus-leukemia from graft-versus-host disease in allogeneic hematopoietic stem cell transplantation

Routine methods to maximize the graft-versus-leukemia (GvL) activity of allogeneic hematopoietic stem cell transplantation (HSCT) without the detrimental effects of graft-versus-host disease (GvHD) are lacking. Depletion or inhibition of alloreactive T cells is partially effective in preventing GvHD, but usually leads to decreased GvL activity. The current model for the pathophysiology of acute GvHD describes a series of immune pathways that lead to activation of donor T cells and inflammatory cytokines responsible for tissue damage in acute GvHD. This model does not account for how allotransplant can lead to GvL effects without GvHD, or how the initial activation of donor immune cells may lead to counter-regulatory effects that limit GvHD. In this review, we will summarize new findings that support a more complex model for the initiation of GvHD and GvL activities in allogeneic HSCT, and discuss the potential of novel strategies to enhance GvL activity of the transplant.

Fatigue in patients with advanced cancer: a pilot study of an intervention with infliximab

GOALS OF WORK

The objective of this study was to determine the effect of infliximab, an antitumor necrosis factor alpha (TNFalpha) antibody, on fatigue in patients with advanced cancer.

MATERIALS AND METHODS

This was a pilot study undertaken in a specialist palliative care unit. Seventeen eligible outpatients were enrolled in this study. Infliximab 5 mg/kg was administered intravenously at baseline and if there was observable clinical benefit, every 4 weeks thereafter until clinical benefit was lost. The primary outcome measure assessing subjective functional improvement was the change in fatigue severity scale (FSS) score at 4 weeks following an infliximab infusion. Secondary outcome measures of subjective functional improvement that were assessed 4 weeks after each infliximab infusion included changes in Karnofsky performance status (KPS), hospital anxiety and depression scale (HADS) score, anxiety and depression subscores, and appetite visual analogue scale. Clinical laboratory assessments were C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), TNFalpha, interleukin-6, and leptin concentrations.

MAIN RESULTS

At week 4, 9 of 14 patients improved in FSS, 3 of 15 improved in KPS, 7 of 15 improved in total HADS and the majority had modest improvements in serum CRP, ESR, or leptin concentrations. Case studies of six patients with overall improvement are described in detail. Five serious adverse events occurred; two were serious infections possibly related to treatment.

CONCLUSIONS

A subgroup of patients in this small pilot study demonstrated uniform subjective/clinical benefit. We were not able to identify any predictors of this response; a larger, controlled study may reveal more information.

Anti-tumor necrosis factor-a for the treatment of steroid-refractory acute graft-versus-host disease

Allogeneic stem cell transplantation has been increasingly performed for a variety of hematologic diseases. Clinically significant acute graft-versus-host disease (GVHD) occurs in 9 to 50% of patients who receive allogeneic grafts, resulting in high morbidity and mortality. There is no standard therapy for patients with acute GVHD who do not respond to steroids. Studies have shown a possible benefit of anti-TNF-a (infliximab)for the treatment of acute GVHD. We report here on the outcomes of 10 recipients of related or unrelated stem cell transplants who received 10 mg/kg infliximab, iv, once weekly for a median of 3.5 doses (range: 1-6) for the treatment of severe acute GVHD and who were not responsive to standard therapy. All patients had acute GVHD grades II to IV (II = 2, III = 3, IV = 5). Overall, 9 patients responded and 1 patient had progressive disease. Among the responders, 3 had complete responses and 6 partial responses. All patients with cutaneous or gastrointestinal involvement responded, while only 2 of 6 patients with liver disease showed any response. None of the 10 patients had any kind of immediate toxicity. Four patients died, all of them with sepsis. Six patients are still alive after a median follow-up time of 544 days (92-600) after transplantation. Considering the severity of the cases and the bad prognosis associated with advanced acute GVHD, we find our results encouraging. Anti-TNF-a seems to be a useful agent for the treatment of acute GVHD.

How I treat refractory acute GVHD

Graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT) is associated with considerable morbidity and mortality, particularly in patients who do not respond to primary therapy, which usually consists of glucocorticoids (steroids). Approaches to therapy of acute GVHD refractory to "standard" doses of steroids have ranged from increasing the dose of steroids to the addition of polyclonal or monoclonal antibodies, the use of immunotoxins, additional immunosuppressive/chemotherapeutic interventions, phototherapy, and other means. While many pilot studies have yielded encouraging response rates, in most of these studies long-term survival was not improved in comparison with that seen with the use of steroids alone. A major reason for failure has been the high rate of infections, including invasive fungal, bacterial, and viral infections. It is difficult to conduct controlled prospective trials in the setting of steroid-refractory GVHD, and a custom-tailored therapy dependent upon the time after HCT, specific organ manifestations of GVHD, and severity is appropriate. All patients being treated for GVHD should also receive intensive prophylaxis against infectious complications.

Off-label uses of biologics in dermatology: Rituximab, omalizumab, infliximab, etanercept, adalimumab, efalizumab, and alefacept (Part 2 of 2)

Recently, dermatologists have witnessed a revolution in our therapeutic armamentarium with the development of several novel biologic immunomodulators. Although psoriasis remains the only condition in dermatology for which the use of biologic immunomodulators has been approved by the Food and Drug Administration, these drugs have the potential to significantly impact the treatment of several inflammatory conditions in dermatology. This article includes a review of the mechanism of action, dosing, and side-effect profile, as well as a review of the current literature on off-label uses of the CD20-positive B-cell antagonist rituximab, the IgE antagonist omalizumab, the tumor necrosis factor-alpha antagonists infliximab, etanercept, and adalimumab, and the T-cell response modifiers efalizumab and alefacept.

Anorectal carcinoma after infliximab therapy in Crohn's disease: report of a case

Infliximab, monoclonal antibody against tumor necrosis factor alpha, is an effective agent in the therapy of Crohn's disease. Although therapy with infliximab is generally well tolerated, there is an obvious concern about the effect of this treatment on the incidence of cancer. We report a case of mucinous anorectal adenocarcinoma observed in a 39-year-old patient with long-standing Crohn's disease after therapy with two courses of infliximab. The carcinoma was discovered fortuitously after abdominoperineal resection. Despite clear margins, the tumor recurred in a few months and progressed during combination chemotherapy. Although there is currently no definitive proof of a causal link between infliximab therapy and cancer, the present observation and other reports in the literature should lead to a careful evaluation of the possibility of increased cancer risk in patients treated with this new agent.

The down-regulation of IL1alpha and IL6, in monocytes exposed to extracorporeal photopheresis (ECP)-treated lymphocytes, is not dependent on lymphocyte phosphatidylserine externalization

Extracorporeal photopheresis (ECP) has been successfully used to treat some inflammatory conditions. Following ECP, lymphocytes become apoptotic and untreated monocytes, exposed to post-ECP lymphocytes, reduce proinflammatory cytokine secretion. This study attempted to establish if this monocyte immunosuppression was linked to phosphatidylserine externalization (detected using Annexin V) on the apoptotic lymphocytes. Using density gradient and magnetic separation, lymphocytes were isolated from three cutaneous T-cell lymphoma and nine chronic graft versus host disease (cGvHD) patients pre-ECP and prior to re-infusion (post-ECP). The collected lymphocytes were cultured overnight and Annexin V levels determined. Peripheral blood was taken from the same patient 20 h later and the monocytes were isolated. The 'fresh' monocytes were introduced to each 20 h pre- and post-ECP lymphocyte culture, stimulated with lipopolysaccharide (LPS) and Brefeldin A and subsequently tested for intracellular tumour necrosis factor alpha, interleukin 1 alpha (IL1alpha), IL1beta, IL6 and IL8. For cGvHD patients, the relative levels of IL1alpha and IL6 were reduced in the untreated, LPS-stimulated monocytes exposed to post-ECP lymphocytes. However, the down-regulation of IL1alpha and IL6 did not correlate to levels of Annexin V-positive lymphocytes. ECP-treated lymphocytes can reduce the ability of LPS-stimulated monocytes to produce some proinflammatory cytokines; however, this effect is not dependent on phosphatidylserine externalization.

Therapy for severe refractory acute graft-versus-host disease with basiliximab, a selective interleukin-2 receptor antagonist

Basiliximab is a chimeric monoclonal antibody that binds to the alpha chain of IL-2R on activated cytotoxic T-cells, inhibiting lymphocyte proliferation. We report 34 patients with refractory acute GVHD (grade III-IV) who received basiliximab from December 1998 to October 2003. Adults received 40 mg weekly (2-3 doses) and children received half of this dose. Median age was 13 years. Twenty-five donors were unrelated. The stem cell source was bone marrow in 30 and cord blood in four. Complete responses were seen in 27/32 patients (84%) with skin, 12/25 (48%) with gut and 6/23 (26%) with liver GVHD. Median duration of response was 38 days (5-1103). Overall survival at 5 years was 20%. Eleven patients (32%) are alive. The main causes of death were CMV (n=4), fungus (n=6), sepsis (n=8), hemorrhage (n=2), and relapse (n=2). Graft-versus-host disease flares were observed in 14 patients (41%), half being rescued by other therapies. In conclusion, basiliximab was able to induce complete responses in patients with refractory acute GVHD. Prospective studies are necessary to evaluate the optimal treatment schedule.

Biologics in the treatment of transplant rejection and ischemia/reperfusion injury: new applications for TNFalpha inhibitors?

Tumor necrosis factor (TNF)-alpha inhibitors have proven efficacy in various autoimmune diseases such as Crohn disease, rheumatoid arthritis, psoriasis, and ankylosing spondylitis. Indeed, some TNFalpha inhibitors have already been approved for the management of the inflammatory manifestations associated with Crohn disease and rheumatoid arthritis. These agents are increasingly used for treatment of corticosteroid-resistant graft-versus-host disease after bone marrow transplantation, and case reports have documented their efficacy in treating corticosteroid- and muromonab-resistant rejection after intestinal transplantation. Thus, the potential role of TNFalpha inhibitors in transplantation of other vascularized solid organs is worthy of investigation. Experimental evidence indicates that TNFalpha plays a key role in mediating ischemia/reperfusion (IR) injury after liver, kidney, intestine, heart, lung, and pancreas transplantation. TNFalpha was also identified as a marker cytokine during organ rejection. Single-center studies evaluating the role of TNFalpha inhibitors in kidney transplantation have been initiated but the results are not yet available. TNFalpha is known to be a contributing factor in kidney allograft rejection, and may have value in predicting the onset of steroid-resistant acute rejection after liver transplantation. Experimental and preliminary clinical data have shown that circulating levels of TNFalpha are increased during cardiac graft rejection, and indicate that TNFalpha plays a role in the pathogenesis of acute cardiac allograft rejection. Anti-TNFalpha therapy was shown to prolong cardiac allograft survival when used alone or in combination with other drugs. TNFalpha genotype has been strongly associated with mortality in humans due to acute cell-mediated heart transplant rejection. In addition, there is evidence for a genetic predisposition toward acute rejection after kidney and simultaneous kidney-pancreas transplantation. TNFalpha inhibition has been used successfully as part of an induction therapy for pancreatic islet cell transplantation. Apart from IR injury and acute rejection after lung transplantation, TNFalpha was also found to be involved in the pathoimmunology of obliterative bronchiolitis. In conclusion, a substantial body of experimental evidence and preliminary clinical data suggest that TNFalpha inhibitors may play an important role in solid-organ transplantation, both in the amelioration of IR injury and in the treatment and prevention of acute rejection. Pharmacodynamic monitoring and pharmacogenetic screening may help to identify patients most likely to benefit from TNFalpha blockade. Randomized controlled trials in patients undergoing solid-organ transplantation are needed to further elucidate the clinical value of TNFalpha inhibition.

Approaches to graft-vs-host disease

Graft-vs-host disease (GVHD) is one of the most difficult problems in stem cell transplantation. It is best considered in the context of the normal immune response. The role of the immune system is to identify and eliminate foreign antigens. In the case of GVHD, the antigens are minor histocompatibility antigens (mHA) recognized in an inflammatory milieu. The immune system cannot reasonably be expected to selectively recognize microbial antigens and ignore mHA. This approach would require the generation of selective tolerance--something that clearly occurs but which we have frustratingly little control over. While we can often treat and remit even life-threatening GVHD, the consequence has been the development of fatal opportunistic infections. The challenge is to change our style of thinking about GVHD to allow a transition from a 'nuclear winter' approach that controls GVHD at the price of infection, to a more selective patient approach that recognizes the limitations of immunosuppressive therapy.

Dermatologic treatment of cutaneous graft versus host disease

Cutaneous involvement in graft versus host disease (GVHD) after allogeneic hematopoietic cell transplant can be separated into acute GVHD (aGVHD), lichenoid chronic GVHD (cGVHD) and sclerodermatous cGVHD. It seems clear that these syndromes result from different mechanisms and entail different treatment approaches. Standard treatment of cutaneous aGVHD involves the intensification of immunosuppressive therapy with adequate topical supportive management. In skin-limited disease, phototherapy has shown promising results. In cutaneous cGVHD, the combination of corticosteroids and cyclosporine (ciclosporin) is the recommended therapy, and other immunosuppressants may be added depending on whether lichenoid or sclerodermatous lesions are present. High response rates to phototherapy have been found in lichenoid disease, while sclerodermatous disease responds better to etretinate or extracorporeal photochemotherapy. Localized cutaneous cGVHD may be treated with topical corticosteroids alone. Few reports on the effect of treatments in GVHD clearly describe the cutaneous involvement and the influence of the treatment on the skin. Therefore, dermatologists should be deeply involved in the diagnosis and treatment of GVHD, and good dermatologic grading systems should be developed. Theses changes will increase our knowledge of cutaneous GVHD, and relevant data in the evaluation of the effect of therapy in the disease will be obtained.

Life-threatening graft-vs-host disease

Hematopoietic stem cell transplant (SCT) is considered standard therapy for a variety of malignant and nonmalignant diseases. Graft-versus-host disease (GVHD) still represents today a major complication of hematopoietic SCT. Two types of GVHD have traditionally been recognized on the basis of the time of onset following transplantation, distinct pathobiological pathways, and different clinical presentations. The acute form commonly breaks out 2 to 6 weeks after transplantation, affecting up to 60% of patients receiving allogeneic transplants from HLA identical donors. Transfer of immunocompetent donor T cells contained in the graft may undergo alloreactivity against recipient cells because of major or minor histocompatibility antigens disparities between the donor and the immunosuppressed host. Target specificity in acute GVHD involves preferential injury to epithelial surfaces of the skin and mucous membranes, biliary ducts of the liver, and crypts of the intestinal tract. Chronic GVHD affects approximately 30% to 80% of patients surviving 6 months or longer after stem cell transplantation and is the leading cause of nonrelapse deaths occurring more than 2 years after transplantation. Chronic GVHD is a multiorgan syndrome with clinical features suggesting some autoimmune diseases, and possibly both alloreactive and autoreactive T cell clones are involved in its pathophysiology. Although GVHD may convey beneficial graft-versus-leukemia/lymphoma effects, it also entails a significant risk of morbidity and mortality. Patients with mild GVHD need only minimal, if any, immunosuppressive treatment, whereas prognosis of patients with extensive disease or resistant to standard immunosuppressive treatment may be dismal. Early recognition of GVHD followed by prompt therapeutic intervention may prevent the progression to higher-grade disease and improve the outcome for patients receiving hematopoietic SCT.

Emerging therapies for graft-versus-host disease

Acute graft-versus-host disease (GVHD) and chronic GVHD remain the major barriers to successful haematopoietic cell transplantation. The induction of GVHD may be divided into three phases: (i) recipient conditioning, (ii) donor T cell activation, and (iii) effector cells mediating GVHD. Standard agents and agents under development to prevent and treat GVHD are discussed. The various pharmacological agents impact on different phases of the GVHD cascade. Sirolimus is a new immunophilin binding agent that appears to be synergistic with tacrolimus and cyclosporin. It also seems to promote allograft tolerance. Mycophenolate mofetil (MMF) is an antimetabolite that is currently under study for prophylaxis and treatment of acute and chronic GVHD; results are encouraging. Other agents such as the purine analogue pentostatin and the monoclonal antibodies alemtuzumab, daclizumab and infliximab are discussed at length within the GVHD context. The most effective approach to GVHD prevention will likely be a combination regimen where the three phases of the GVHD cascade are disrupted. Once GVHD has occurred, all three phases of the cascade are activated. Developments of combination therapy for the treatment of both acute and chronic GVHD will likely yield better results than monotherapy. The numerous new treatment modalities presented should improve the outlook for acute and chronic GVHD.

Translating basic science into patient therapy for ANCA-associated small vessel vasculitis

ANCA (anti-neutrophil cytoplasm antibody)-associated small vessel vasculitis is an inflammatory condition associated with the production of autoantibodies to neutrophil cytoplasmic components. The disorder results in destruction of the microvasculature, infiltration of neutrophils into tissues, which is followed later by mononuclear cells, leading to injury and the formation of granulomatous lesions. Initiators for the disease are undetermined but a pro-inflammatory environment is required. Other influencing factors may include environmental triggers, genetic propensity or infectious agents. The primary cellular event in the condition involves the neutrophils, which are likely to be responsible for the majority of tissue injury. Binding of the autoantibody to neutrophils initiates cell activation via a complex intracellular signalling cascade, culminating in the release of pro-inflammatory mediators, proteolytic enzymes and reactive oxygen species. Adhesion of neutrophils to endothelial cells is observed in vitro and more investigations in this area may explain the focussing of the disease to certain vessels/tissues. Current treatment regimens have substantial toxicity. Although newer developments are an improvement there is still a pressing need for more targeted therapies, which could be provided by extrapolating information emerging from basic scientific research.

Tumor necrosis factor-alpha blockade for the treatment of acute GVHD

Despite posttransplantation immunosuppressive therapy, acute graft-versus-host disease (GVHD) remains a major cause of sickness and death. Tumor necrosis factor-alpha (TNF-alpha) is implicated in the pathophysiology of GVHD at several steps in the process. Infliximab is a genetically constructed immunoglobulin G1 (IgG1) murine-human chimeric monoclonal antibody that binds the soluble subunit and the membrane-bound precursor of TNF-alpha, blocking its interaction with receptors and causing lysis of cells that produce TNF-alpha. In this study we retrospectively evaluated 134 patients who had steroid-refractory acute GVHD. Of these, 21 who received infliximab as a single agent were analyzed. The overall response rate was 67% (n = 14), and 13 patients (62%) experienced complete response (CR). Five patients (24%) did not respond, and 2 (10%) had progressive GVHD. None had a toxic reaction to infliximab. Ten patients (48%) had 18 fungal infections, including Aspergillus species in 7 and Candida species in 10. Seventeen patients (81%) had bacterial infections, including 32 gram-positive and 8 gram-negative infections. Viral infections, primarily cytomegalovirus reactivation, occurred in 14 patients (67%). The Kaplan-Meier estimate of overall survival was 38%. In conclusion, infliximab was well tolerated and active for the treatment of steroid-resistant acute GVHD, particularly with gastrointestinal tract involvement. Survival after steroid-resistant acute GVHD continues to be problematic. The possibility of excessive fungal and other infections must be explored further.

Clinical "cytokine storm" as revealed by monocyte intracellular flow cytometry: correlation of tumor necrosis factor alpha with severe gut graft-versus-host disease

BACKGROUND & AIMS

Gut graft-versus-host disease (GVHD) contributes significantly to lethality after allogeneic hematopoietic stem-cell transplantation (HSCT). In murine models, macrophage secretion of interleukin 1alpha (IL-1alpha) and tumor necrosis factor alpha (TNF-alpha) contributes to gut GVHD pathogenesis. To help characterize whether human gut GVHD has similar biological characteristics, monocyte IL-1alpha and TNF-alpha production were evaluated after HSCT.

METHODS

Patients with refractory hematologic malignancy (n = 17) underwent reduced-intensity conditioning, HLA-matched sibling HSCT, and cyclosporine A GVHD prophylaxis. After HSCT, monocyte IL-1alpha and TNF-alpha levels were measured using intracellular flow cytometry (IC-FCM), and results were correlated with clinical GVHD.

RESULTS

Incidences of acute GVHD were none (n = 3), grades I-II (n = 9), or grades III-IV (n = 5; each case with stage 2-3 gut GVHD). Posttransplantation monocyte IL-1alpha production (percentage of CD14(+)IL-1(+) cells) increased significantly from 8.7% +/- 3.7% (week 2) to 40.3% +/- 7.3% (week 4; P = 0.0065) and was not associated with GVHD severity (P = 1.00). Conversely, increases in monocyte TNF-alpha were quantitatively reduced and temporally delayed, from 0.6% +/- 0.2% (week 2) to 3.6% +/- 1.4% (week 6; P = 0.076). Most importantly, elevation of monocyte TNF-alpha level correlated with increased gut GVHD severity (P = 0.0041); increases in monocyte TNF-alpha levels typically preceded the onset of gut GVHD symptoms.

CONCLUSIONS

Human gut GVHD after reduced-intensity allogeneic HSCT is associated with monocyte cytokine secretion initially involving IL-1alpha, followed by TNF-alpha. Serial measurement of monocyte cytokines, in particular, TNF-alpha, by IC-FCM may represent a noninvasive method for GVHD monitoring, potentially allowing the identification of patients appropriate for early-intervention strategies.

Acute and chronic graft-versus-host disease after ablative and nonmyeloablative conditioning for allogeneic hematopoietic transplantation

In this study, we evaluated the influence of nonmyeloablative and ablative conditioning regimens on the occurrence of acute and chronic graft-versus-host disease (GVHD). One hundred thirty-seven patients undergoing matched-related sibling transplantations received the same GVHD prophylaxis. Myeloablative regimens included intravenous busulfan/cyclophosphamide (n=45) and fludarabine/melphalan (n=29). Patients in the nonmyeloablative group (n=63) received fludarabine/idarubicin/cytarabine, cisplatin/fludarabine/idarubicin, and fludarabine/cyclophosphamide. The actuarial rate of grade II to IV acute GVHD was significantly higher (hazard ratio, 3.6; 95% confidence interval, 1.5-8.8) in patients receiving ablative regimens (36%) compared with the nonmyeloablative group (12%). The cumulative incidence of chronic GVHD was higher in the ablative group (40%) compared with the nonmyeloablative group (14%). The rates were comparable within the first 200 days and were significantly higher in the ablative group beyond day 200 (hazard ratio, 5.2; 95% confidence interval, 1.2-23.2). Nonrelapse and GVHD-related mortality were relatively low in both groups. The use of the described nonmyeloablative preparative regimens was associated with a reduced incidence of grade II to IV acute GVHD and chronic GVHD compared with the busulfan/cyclophosphamide and fludarabine/melphalan transplant regimens. It is interesting to note that nonrelapse mortality with nonmyeloablative regimens in older and more debilitated patients was low (14%) and comparable to that achieved with standard high-dose regimens in younger patients.

Novel immunotherapies for psoriasis: clinical research delivers new hope for patients and scientific advances

Immunobiologics provide the hope for safe and effective long-term management of psoriasis, a life-disabling condition. The use of targeted immunotherapies as pathogenic probes has led to scientific discoveries that help uncover new information on the pathogenesis of psoriasis and on the control of cutaneous immunity. The research described in this paper employs targeted immunotherapies as pathogenic probes of T1-mediated immune disorders, using psoriasis as the primary disease model. This approach has wide applicability to other immune-mediated inflammatory isorders.

Infliximab use in patients with severe graft-versus-host disease and other emerging risk factors of non-Candida invasive fungal infections in allogeneic hematopoietic stem cell transplant recipients: a cohort study

Acute graft-versus-host disease (GVHD) is a common complication of allogeneic hematopoietic stem cell transplantation (HSCT). It has been proposed that tumor necrosis factor alpha (TNF-alpha) blockade with infliximab may be an effective treatment for severe (grades III-IV) GVHD. We determined if infliximab use in this high-risk population was associated with an additional increased risk of non-Candida invasive fungal infections (IFIs). Records of the 2000-2001 HSCT cohort at our institution were reviewed. Fifty-three (20%) of 264 evaluable patients developed severe GVHD and 11 of these 53 (21%) received infliximab for treatment. Proven or probable IFI was documented in 10 (19%) of 53 patients with severe GVHD (incidence rate of 0.99 cases/1000 GVHD patient-days). When stratified by infliximab use, 5 of 11 infliximab recipients developed an IFI (6.78 cases/1000 GVHD patient-days), compared with 5 of 42 IFI cases among nonrecipients (0.53 cases/1000 GVHD patient-days). In a time-dependent Cox regression model among patients with severe GVHD, the adjusted IFI hazard ratio of infliximab exposure was 13.6 (P =.004; 95% CI, 2.29-80.2). We conclude that infliximab administration is associated with a significantly increased risk of non-Candida IFI in HSCT recipients with severe GVHD disease. Pre-emptive systemic antifungal therapy against molds should be considered in patients who develop severe GVHD after HSCT if infliximab is used.

Infliximab for steroid-refractory acute GVHD: a case series

Acute and chronic graft-versus-host disease (GVHD) remain major barriers to successful hematopoietic stem cell transplantation (SCT). TNF-alpha has been implicated in the pathogenesis of GVHD and TNF-alpha blockade has been explored for treatment of GVHD. The development of a chimeric mouse/human monoclonal antibody (infliximab) which binds to cells producing TNF-alpha, allowing for not only the neutralization of TNF-alpha but also lysis of the cells producing the TNF-alpha, makes this an attractive drug to explore in GVHD. We report on 11 patients with acute GVHD who were treated with infliximab after failing other therapies. The survival was very poor, in keeping with previously published reports of steroid-refractory acute GVHD. Two patients with severe diarrhea from acute GI GVHD resolved their symptoms after treatment with infliximab. Only these two patients survived. It appears that of all acute GVHD manifestations, gastrointestinal GVHD may be more responsive to treatment with infliximab than others. Caution is recommended when using this agent since it may exacerbate active infections, particularly aspergillosis. Furthermore, we do not know the correct dose or schedule to use with this drug. Given these data, controlled studies assessing dose and timing of administration may be warranted to study infliximab in acute GVHD.

Signalling pathways of the TNF superfamily: a double-edged sword

Two different tumour-necrosis factors (TNFs), first isolated in 1984, were found to be cytotoxic to tumour cells and to induce tumour regression in mice. Research during the past two decades has shown the existence of a superfamily of TNF proteins consisting of 19 members that signal through 29 receptors. These ligands, while regulating normal functions such as immune responses, haematopoiesis and morphogenesis, have also been implicated in tumorigenesis, transplant rejection, septic shock, viral replication, bone resorption, rheumatoid arthritis and diabetes; so indicating their role as 'double-edged swords'. These cytokines either induce cellular proliferation, survival, differentiation or apoptosis. Blockers of TNF have been approved for human use in treating TNF-linked autoimmune diseases in the United States and other countries.

Clinical research helps elucidate the role of tumor necrosis factor-alpha in the pathogenesis of T1-mediated immune disorders: use of targeted immunotherapeutics as pathogenic probes

Psoriasis is a life-disabling disorder in which 8-10% of patients aged 18-54 actively contemplate suicide because of their disease. Owing to the toxicity and/or inconvenience of current, FDA-approved treatments far moderate-to-severe psoriasis, they are generally used intermittently so that patients experience cycles of remission-flare-remission-flare, etc. The challenge to drug development for moderate-to-severe psoriasis is to provide safe and effective long-term management. Immunobiologics offer the hope for safe, long-term control of psoriasis because they lack targeted organ toxicity. Thus the treatment paradigm may shift from one of intermittent treatment limited by toxicity with resultant flares of disease, to one similar to that seen in diabetes or hypertension in which disease is controlled continuously. Additionally, immunobiologics may alter the natural history of psoriasis. Etanercept, which targets TNF-alpha, controls signs and symptoms and halts joint destruction in patients with psoriatic arthritis. The long-lived remissions observed after cessation of alefacept or infliximab (anti-TNF-alpha monoclonal antibody) treatment lead this author to speculate that these immunobiologics may actually alter the natural history of the cutaneous manifestations of psoriasis.

Successful infliximab treatment of steroid and OKT3 refractory acute cellular rejection in two patients after intestinal transplantation

Acute rejection resistant to established immunosuppressive rescue protocols remains the most prominent risk factor after intestinal transplantation. In two patients presenting with steroid-resistant severe acute cellular rejection 9 months and 2 years after intestinal transplantation, complete resolution was not achieved despite 5 and 10 days of OKT3 treatment, respectively, and high-dose triple baseline immunosuppression with tacrolimus, rapamycin, and steroids. There was a dissociated course of rejection with persistent moderate to severe rejection in the terminal portion of the graft despite complete recovery from rejection in the proximal parts. Both patients were treated with four subsequent infusions of infliximab (3 mg/kg body weight), a chimeric anti-tumor necrosis factor-alpha antibody. There was an immediate response regarding macroscopic appearance, graft histology, and clinical symptoms. Both patients recovered. In conclusion, infliximab has proven to be an effective rescue therapy in a selected group of patients with steroid and OKT3 refractory severe acute rejection after intestinal transplantation.

Potential of p38 MAP kinase inhibitors in the treatment of cancer

The involvement of chronic inflammation in tumor development and progression is reviewed. Based on the natural history of certain diseases and epidemiology studies, a strong association has been established between particular chronic inflammatory conditions and eventual tumor appearance. Solid tumors require a stroma for their growth and recruit macrophages to synthesize essential growth and angiogenic factors that they do not have the capacity to produce. The microenvironment of the local host tissue appears to be an active participant in exchanging cytokines and enzymes with tumor cells that modify the local extracellular matrix, stimulate migration, and promote tumor angiogenesis, proliferation and survival. The role of p38 MAP kinase as a therapeutic target for treating cancer is discussed.

Steroid-refractory graft-vs.-host disease: past, present and future

Despite current standard preventive strategies that include optimizing donor selection and the combination of methorexate and a calcineurine inhibitor, acute and chronic GVHD remains a major barrier to successful hematopoietic cell transplantation for a sizeable proportion of patients. When acute and chronic GVHD become manifest a standard primary therapy approach has been the addition of glucocorticoid therapy to a background of calcineurine inhibition. When this approach fails patients with GVHD require secondary therapy. Ideally, second-line agents should promote transplantation tolerance so that the morbidity associated with prolonged use of glucocorticoids and other immunosuppressive agents can be minimized. Promising new agents or strategies which warrant further controlled clinical trials include: mycophenolate mofetil, sirolimus, humanized or chimeric monoclonal antibodies such as visilizumab, daclizumab and infliximab, and extracorporeal photopheresis. Co-operative studies are necessary to hasten the process of evaluating novel treatment strategies for acute and chronic GVHD.

New indications for treatment of chronic inflammation by TNF-alpha blockade

The impressive anti-inflammatory effects of the tumor necrosis factor (TNF)alpha blockers etanercept and infliximab have led to their use in multiple inflammatory diseases besides their original indication, rheumatoid arthritis (RA). The well-studied clinical effects of both agents in RA are the reduction of signs and symptoms of joint inflammation as well as the arrest of bone destruction. Infliximab has also been Food and Drug Administration-approved in the treatment of Crohn disease; etanercept is now FDA-approved for juvenile chronic arthritis and psoriatic arthritis. Favorable initial clinical trials have been reported in other rheumatic diseases, including ankylosing spondylitis and adult Still disease. In addition, TNF alpha blockade is being studied in the treatment of uveitis, myelodysplastic syndromes, and graft-versus-host disease. Studies in sepsis and septic shock have identified small subsets of patients that may benefit from TNF alpha blockade, but broader use in septic patients has not improved survival. The TNF alpha blockers have had relatively infrequent serious side effects, especially compared with the immunosuppressive and cytotoxic agents otherwise employed to treat these diseases. Further studies of optimal dosing, combination with other therapies, and long-term benefits and side effects will emerge from future trials.

Novel therapeutics for the treatment of graft-versus-host disease

Acute graft-versus-host disease (GVHD) and chronic GVHD remain the major barriers to successful haematopoietic cell transplantation. The induction of GVHD may be divided into three phases: recipient conditioning, donor T cell activation and effector cells mediating GVHD. This review examines GVHD prevention and treatment using this conceptual model as framework. The various pharmacological agents discussed impact on different phases of the GVHD cascade. For example, keratinocyte growth factor and IL-11 are cytokines that may be useful in disrupting Phase I of the GVHD cascade by blocking gastrointestinal tract damage and lowering serum levels of lipopolysaccharide and TNF-alpha. Cyclosporin, FK506 and sirolimus are some of the main agents that disrupt Phase II (donor T cell activation). Mycophenolate mofetil likely acts on this phase as well. Other novel drugs that affect Phase II are tolerance-induction agents such as cytotoxic T lymphocyte antigen (CTLA)-4 Ig and anti-CD40 ligand, and preliminary results using CTLA-4 Ig in GVHD prevention are encouraging. Two exciting agents that appear to affect only activated lymphocytes are ABX-CBL and visilizumab. Examples of agents that disrupt Phase III are the IL-2 receptor antagonist daclizumab and the anti-TNF-alpha monoclonal antibody infliximab. These anticytokine antibodies have shown promising results in early studies. The most effective approach to GVHD prevention will likely be a combination regimen where the three phases of the GVHD cascade are disrupted. Once GVHD has occurred, all three phases of the cascade are activated. Developments of combination therapy for treatment of both acute and chronic GVHD will likely yield better results than monotherapy. The numerous new treatment modalities presented should improve the outlook for acute and chronic GVHD.

The clinical significance of tumor necrosis factor-α plasma level in patients having chronic lymphocytic leukemia

Tumor necrosis factor-α (TNF-α), a cytokine possessing pleiotropic biological activities, is produced by leukemic lymphocytes in patients with chronic lymphocytic leukemia (CLL) and acts as an autocrine and paracrine growth factor in this disease. In this study, TNF-α levels were determined in 150 patients with CLL and correlated with disease characteristics, prognostic factors, and survival. The mean TNF-α plasma concentration in the patients with CLL was significantly higher than in the healthy control population (16.4 versus 8.7 pg/mL; P &lt; .0001). Patients having an elevated TNF-α level had more advanced Rai and Binet stage disease, higher serum β2-microglobulin (β2M) levels, a greater percentage of cells expressing CD38, and lower hemoglobin and platelet levels. Patients having chromosomal abnormalities such as 11q deletion, trisomy 12, and chromosome 17 aberrations had a higher mean TNF-α level (27.5 pg/mL) than patients having a diploid karyotype or other miscellaneous cytogenetic abnormalities (14.2 pg/mL;P &lt; .001). The TNF-α level was a predictor of survival when the Cox proportional hazards model was used with TNF-α entered as a continuous variable (P = .0001). Also, patients having a TNF-α level above the mean value of 14 pg/mL had significantly shorter survival duration (P = .00001). The TNF-α level remained predictive of survival in Cox multivariate analysis independent of Rai staging and β2M, hemoglobin, prior therapy, white cell count, and platelet level (P = .005). We conclude that the TNF-α level serves as a prognostic factor in patients with CLL and that inhibition of TNF-α in these patients could have therapeutic importance.

Novel pharmacotherapeutic approaches to prevention and treatment of GVHD

Acute and chronic graft versus host disease (GVHD) remain the major barriers to successful hematopoietic cell transplantation. The induction of GVHD may be divided into three phases: recipient conditioning;donor T-cell activation; andeffector cells mediating GVHD. This review examines GVHD prevention and treatment using this conceptual model as framework. The various pharmacological agents discussed impact on different phases of the GVHD cascade. For example, keratinocyte growth factor and interleukin (IL)-11 are cytokines that may be useful in disrupting phase I of the GVHD cascade by blocking gastrointestinal tract damage, and lowering serum levels of lipopolysaccharide and tumour necrosis factor (TNF)-alpha. Cyclosporin, tacrolimus (FK-506) and sirolimus (rapamycin) are some of the main agents that disrupt phase II (donor T-cell activation). Mycophenolate mofetil and tresperimus probably act on this phase as well. Other novel drugs that affect phase II are tolerance-induction agents such as CTLA-4 and anti-CD40-ligand monoclonal antibodies, and preliminary results using CTLA-4 monoclonal antibody in GVHD prevention are encouraging. Examples of agents that disrupt phase III are the IL-2 receptor antagonist daclizumab and the anti-TNFalpha monoclonal antibody infliximab. These anti-cytokine antibodies have shown promising results in early studies. The most effective approach to GVHD prevention will probably be a combination regimen where the three phases of the GVHD cascade are disrupted. Once GVHD has occurred, all three phases of the cascade are activated. Developments of combination therapy for treatment of both acute and chronic GVHD are likely to yield better results than monotherapy. The numerous new treatment modalities presented should improve the outlook for patients with acute and chronic GVHD.

A pilot study of the recombinant soluble human tumour necrosis factor receptor (p75)-Fc fusion protein in patients with myelodysplastic syndrome

Laboratory observations suggest that, in some myelodysplastic syndromes (MDS), immune mechanisms may contribute to the impaired blood cell production. Tumor necrosis factor alpha (TNF-alpha), a potent inhibitor of haematopoiesis, has been hypothesized to mediate suppressive effects in MDS: TNF-alpha levels are elevated and correlated with marrow apoptosis and cytopenia. Inhibition of TNF-alpha production using the soluble TNF receptor (Enbrel) has been successful in rheumatoid arthritis, and we have now applied the same principle to MDS. We determined spontaneous TNF-alpha production by marrow cells in MDS; TNF-alpha production was elevated (> mean + 2 x SD of controls) in > 1/3 of patients, but did not correlate with clinical parameters. Sixteen patients participated in a 3-month pilot study of Enbrel. The drug was well tolerated and 15 patients were evaluable. Of these, one became temporarily (14 weeks) transfusion independent. In another patient, absolute neutrophil count (ANC) rose from 0.5 x 10(9)/l to 0.84 x 10(9)/l. Serious infections were seen in two out of six neutropenic patients. Progression to refractory anaemia with excess blasts in transformation (RAEBt) or leukaemia was observed in three patients. When the effects of Enbrel on haematopoietic colony formation were studied, no significant increase was seen in MDS and there was no correlation with TNF-alpha levels. Although anti-TNF therapy with Enbrel was well tolerated at the dosages used in MDS, its efficacy as a single agent appears low.