Oral immunoglobulin treatment in Crohn's disease

Disease modifying drugs for rheumatological diseases: a brief history of everything

The rheumatological diseases are a group of chronic, painful, degenerative and debilitating conditions with an increasing prevalence across the globe. The pathogenesis of these disorders is complex, overlapping and not fully understood. As such, it is difficult and time consuming to achieve correct diagnosis and complete remission for an individual patient. In this review we describe the most common forms of inflammatory arthritis and discuss how the management and treatment options for these rheumatic diseases have developed over time. We outline the successes and the limitations of current treatment regimens and discuss the economic burden of the current options. With advancements in understanding of disease mechanisms, we discuss the importance of the biologics revolution in the context of rheumatological disease and how the development of biosimilars and small molecule inhibitors will impact current treatment options in order to alleviate some of the cost burden of biological therapies. The ideal treatment strategy for the future would involve personalized and predictive medicine where by treatments can be tailored to an individual patient's needs in order to achieve fast and successful remission with no adverse events.

Inflammatory bowel disease and targeted oral anti-TNFα therapy

Antibodies have provided invaluable treatment options for many diseases, with immunotherapy revolutionising the treatment of several inflammatory disorders including inflammatory bowel disease (IBD). Accumulating evidence suggests that IBD results from an inappropriate response to intestinal microbes and environmental factors in genetically susceptible individuals, with overactivity of the pro-inflammatory pathways. On a pathophysiological level, IBD is a complex disease with intestinal fibrosis, stenosis and an increased incidence of cancer observed in those whose disease is inadequately controlled over time. Regulating the actions of the pro-inflammatory cytokine human tumor necrosis factor-alpha (hTNFα) through the use of anti-TNFα monoclonal antibodies (e.g. infliximab, certolizumab, adalimumab and golimumab) has proven an effective intervention for IBD with their increased use a testament of their effectiveness. These agents are administered systemically thereby causing their distribution throughout the body in a condition that is localised to the gastrointestinal (GI) tract. Immunogenicity, the induction of anti-drug antibodies (ADAs), serum sickness and other undesirable side effects limit their use, whilst up to 50% of patients do not respond to initial therapy. Diseases confined to the GI tract are ideal for targeting by oral therapy which mitigates side effects and allows for lower doses to be administered. Several oral anti-TNFα agents have been investigated with success but are not yet in general clinical use. This partially reflects the fact that the oral administration of antibodies has many barriers including the harsh environment of the GI tract and the presence of enzymes including pepsin, trypsin and chymotrypsin in the intestine which provide significant challenges to targeted oral therapy.

Oral immunoglobulin treatment improved intestinal permeability in children with active Crohn's disease

AIM

Crohn's disease (CD) is a chronic mucosal inflammation that affects the intestinal barrier function, for example, by altering the intestinal permeability. This pilot clinical study investigated the impact of oral human immunoglobulin (OHIG) treatment on permeability characteristics in children with active luminal Crohn's disease.

METHODS

The study was performed at the Department of Paediatrics, Norrköping Hospital, Sweden. Intestinal permeability was studied in three boys aged 13, 15 and 18 years with active CD, before and after a six-week treatment programme with OHIG, using different-sized polyethylene glycols as the test molecules. Three age- and sex-matched children with active CD treated with exclusive enteral nutrition (EEN) were also studied.

RESULTS

OHIG and EEN resulted in virtually similar reductions in the signs and symptoms of mucosal inflammation. However, OHIG, unlike EEN, appeared to normalise mucosal transfer leading to a normalisation of the maximum permeation of the small PEG molecules, as well as less restrictions of the larger PEG molecules.

CONCLUSION

Our study found that OHIG appeared to normalise the mucosal barrier. This suggests that it could offer a new additional and versatile treatment for paediatric CD patients, with a minimal risk of adverse effects.

Targeted localized use of therapeutic antibodies: a review of non-systemic, topical and oral applications

Therapeutic antibodies provide important tools in the "medicine chest" of today's clinician for the treatment of a range of disorders. Typically monoclonal or polyclonal antibodies are administered in large doses, either directly or indirectly into the circulation, via a systemic route which is well suited for disseminated ailments. Diseases confined within a specific localized tissue, however, may be treated more effectively and at reduced cost by a delivery system which targets directly the affected area. To explore the advantages of the local administration of antibodies, we reviewed current alternative, non-systemic delivery approaches which are in clinical use, being trialed or developed. These less conventional approaches comprise: (a) local injections, (b) topical and (c) peroral administration routes. Local delivery includes intra-ocular injections into the vitreal humor (i.e. Ranibizumab for age-related macular degeneration), subconjunctival injections (e.g. Bevacizumab for corneal neovascularization), intra-articular joint injections (i.e. anti-TNF alpha antibody for persistent inflammatory monoarthritis) and intratumoral or peritumoral injections (e.g. Ipilimumab for cancer). A range of other strategies, such as the local use of antibacterial antibodies, are also presented. Local injections of antibodies utilize doses which range from 1/10th to 1/100th of the required systemic dose therefore reducing both side-effects and treatment costs. In addition, any therapeutic antibody escaping from the local site of disease into the systemic circulation is immediately diluted within the large blood volume, further lowering the potential for unwanted effects. Needle-free topical application routes become an option when the condition is restricted locally to an external surface. The topical route may potentially be utilized in the form of eye drops for infections or corneal neovascularization or be applied to diseased skin for psoriasis, dermatitis, pyoderma gangrenosum, antibiotic resistant bacterial infections or ulcerated wounds. Diseases confined to the gastrointestinal tract can be targeted directly by applying antibody via the injection-free peroral route. The gastrointestinal tract is unusual in that its natural immuno-tolerant nature ensures the long-term safety of repeatedly ingesting heterologous antiserum or antibody materials. Without the stringent regulatory, purity and clean room requirements of manufacturing parenteral (injectable) antibodies, production costs are minimal, with the potential for more direct low-cost targeting of gastrointestinal diseases, especially with those caused by problematic antibiotic resistant or toxigenic bacteria (e.g. Clostridium difficile, Helicobacter pylori), viruses (e.g. rotavirus, norovirus) or inflammatory bowel disease (e.g. ulcerative colitis, Crohn's disease). Use of the oral route has previously been hindered by excessive antibody digestion within the gastrointestinal tract; however, this limitation may be overcome by intelligently applying one or more strategies (i.e. decoy proteins, masking therapeutic antibody cleavage sites, pH modulation, enzyme inhibition or encapsulation). These aspects are additionally discussed in this review and novel insights also provided. With the development of new applications via local injections, topical and peroral routes, it is envisaged that an extended range of ailments will increasingly fall within the clinical scope of therapeutic antibodies further expanding this market.

Intravenous immunoglobulin for the treatment of Crohn's disease

Crohn's disease (CD) is a debilitating condition which still requires improvement in its management. There is a need for alternatives to anti-tumour necrosis factor drugs which are costly and beneficial in less than 50% of patients. Intravenous immunoglobulin (IVIG) has been used in the management of aminosalicylate- and steroid-resistant CD for more than 20 years, although the published literature available is limited. A literature search identified 17 relevant publications since 1969, including five case reports of single patients, two abstracts, three conference papers, one review paper and six book or journal articles. No randomised controlled trials of IVIG in CD have been published. A review of the evidence identified indicates that IVIG can induce a rapid and significant improvement in aminosalicylate- and steroid-resistant CD, often within days of the initial administration. Data from longer-term studies show that maintenance of remission over the medium term is also possible. These encouraging findings provide a rationale for the initiation of larger randomised controlled trials of IVIG in CD with the aim of providing further treatment options for this difficult-to-manage condition.

A double-blind, placebo-controlled trial of oral human immunoglobulin for gastrointestinal dysfunction in children with autistic disorder

Controversy exists regarding the extent and possible causal relationship between gastrointestinal symptoms and autism. A randomized, double-blind, placebo-controlled, parallel groups, dose-ranging study of oral, human immunoglobulin (IGOH 140, 420, or 840 mg/day) was utilized with 125 children (ages 2-17 years) with autism and persistent GI symptoms. Endpoint analysis revealed no significant differences across treatment groups on a modified global improvement scale (validated in irritable bowel syndrome studies), number of daily bowel movements, days of constipation, or severity of problem behaviors. IGOH was well-tolerated; there were no serious adverse events. This study demonstrates the importance of conducting rigorous trials in children with autism and casts doubt on one GI mechanism presumed to exert etiological and/or symptomatic effects in this population.

Intestinal barrier: an interface between health and disease

The intestine constitutes the largest interface between a person and his or her environment, and an intact intestinal barrier is thus essential in maintaining health and preventing tissue injury and several diseases. The intestinal barrier has various immunological and non-immunological components. The epithelial barrier is one of the most important non-immunological components. Hyperpermeability of this barrier is believed to contribute to the pathogenesis of several gastrointestinal disorders including inflammatory bowel disease, celiac disease and food allergy. Hence, assessing barrier integrity is of the utmost importance. One of the more quantitative gauges for this assessment is transepithelial permeability of various molecular probes, among which sugars are commonly used. Measures of intestinal permeability might also be useful as markers for assessment of prognosis and follow up in various gastrointestinal disorders. The present article is a review of the normal and abnormal functioning of the intestinal barrier, the diseases that can result from loss of barrier integrity, and some promising agents and strategies for restoring barrier normality and integrity.

Passive immunity against rotavirus in infants

Passive immunity against a variety of gastrointestinal infections, using orally administered human antibodies, has been tried in a number of clinical trials. Recently, antibodies from other species such as cows and chickens, which have shown efficacy in experimental animal systems, have also been tried in humans. This review summarizes published data on the use of immunoglobulin-containing preparations for prophylaxis and therapy against rotavirus infections in infants and children, and directions for their future use are suggested.