Certolizumab pegol: a TNF-{alpha} antagonist for the treatment of moderate-to-severe Crohn's disease

Breaking through the therapeutic ceiling of inflammatory bowel disease: Dual-targeted therapies

Emerging biologics and small-molecule drugs have changed the clinical status quo of inflammatory bowel disease (IBD). However, current treatments remain at a standstill in terms of response and remission in many cases. Accumulating evidence indicates that dual-targeted therapy (DTT) could be promising in overcoming the existing ceiling of IBD treatment. However, data on the efficacy and safety of DTT on Crohn's disease and ulcerative colitis are still limited or insufficient. Moreover, there is a lack of studies delineating the mechanisms of DTT. Given that various targeted drugs have different targets among the extensive redundant inflammatory networks, DTT could result in various outcomes. In this review, we have summarized the current data on the safety, effectiveness, and clinical development status of novel targeted drugs related to refractory IBD, and have explored the mechanism of action of therapy. We have categorized therapeutic agents into "Therapeutic Agents Targeting Cellular Signaling Pathways" and "Therapeutic Agents Targeting Leukocyte Trafficking" based on the different therapeutic targets, and also by classifying therapeutic agents targeting the cellular signaling pathways into "JAK-dependent" and "JAK-independent," and placed the existing drug combinations into 3 categories based on their mechanisms, namely, overlapping, synergistic, and complementary effects. Lastly, we have proposed the possible mechanisms of DTT to conceive a theoretical framework for clinical decision-making and further drug development and research from an IBD standpoint.

Comparison of remicade to curcumin for the treatment of Crohn's disease: A systematic review

OBJECTIVE

The aim of this study was to review the literature to assess if there is evidence to support the use of Curcumin as a safe complementary therapy in treating Crohn's Disease (CD) in conjunction with Remicade.

DESIGN

Systematic searches were performed by three researchers using electronic databases (ProQuest Medical Library, CINAHL Complete, and PUBMED) to locate and identify articles to meet a predetermined set of inclusion criteria. Specifically full text, peer-reviewed articles published after 2007 were included if they studied human participants 18 years or older.

RESULTS

Tumor necrosis factor-alpha (TNF-a) and Interleukin-1 (IL-1) levels increase in CD patients. Remicade reduces TNF-a in adults with CD. The issues are eventual loss of response (LOR) once IL-1 increases, and severe risks such as malignancy. CD patients using Curcumin saw a 55 point mean reduction in the Crohn's Disease Activity Index, reducing IL-1 and Crp. Plus it reduced TNF-a and PPMTase which improved colorectal cancer outcomes.

CONCLUSIONS

LOR of Remicade occurs when IL-1 increases, and it can cause malignancy. Research shows Curcumin reduces IL-1 and improves cancer outcomes. Future research, using both Remicade and Curcumin, would have to be done, but preliminary data would suggest using both would reduce LOR. Curcumin, even by itself, was found to be a cheap and safe way to reduce CD symptoms and inflammatory markers.

Inflammatory bowel disease meta-evidence and its challenges: is it time to restructure surgical research?

AIM

The aim of this study was to compare the methodological quality and input paper characteristics of systematic reviews and meta-analyses reported in the medical and surgical literature by performing a systematic 'overview of reviews'. Ulcerative colitis (UC) and Crohn's disease (CD) were used as the framework for this comparison as they are relatively common serious conditions, with both medical and surgical options for therapy.

METHOD

Medline, Embase, CINHAL and the Cochrane Database were searched to November 2013. Eligible papers were systematic reviews or meta-analyses that considered a question of therapy in CD or UC. Two independent reviewers selected the papers, extracted the data and scored their methodology using the AMSTAR scoring system. The papers were categorized into medical therapy (M), surgical therapy (S) or medical and surgical therapy (MS) groups. Following retrieval of the sample of meta-evidence papers, the original input studies used in their creation were identified and a search of Medline, Embase, CINHAL and the Cochrane Database was performed. A team of researchers then examined the collection of papers for bibliographic and financial information.

RESULTS

Five hundred papers were identified in the meta-evidence search, of which 118 were deemed eligible. There was a difference in the AMSTAR-rated average quality of the papers between the S and M group (S 7.36 vs M 8.75, P = 0.01). On average S papers were published in journals with a lower impact factor (S 3.26, M 5.04, MS 5.30, P < 0.001). S papers also showed more heterogeneity (I(2) ; S 37%, M 24%, MS 10%, P < 0.001). Some 25% of S meta-analyses used data-sets with significant heterogeneity (I(2) > 75%), compared with 8% of M meta-analyses and 3% of the MS meta-analyses. Some 5% of S papers were done on data sets that had I(2) values > 90%. There was no difference in the average number of papers assessed in each group, the average number of patients per meta-paper, the average time covered by the reviews, the average number of papers considered within each meta-analysis, or the average number of patients considered within each meta-analysis. Considering the conclusions of each meta-analysis, S meta-evidence was 50% more likely than M meta-evidence to be unable to make recommendations for practice. A total of 1499 original input papers were identified, of which 283 were used in more than one review. Within the non-repeated papers (n = 1023) the average impact factor within the S group was lower than that of the M and the MS groups (3.720 vs 11.230 vs 7.563, respectively; ANOVAP < 0.001). M papers had higher rates of pharmaceutical sponsorship than S papers (M 56% vs S 1%) and twice the level of government support (M 16% vs S 8%). Of note, 21% of M papers had corporate sponsorship but did not list any conflict of interest.

CONCLUSION

Compared with M meta-analyses, S meta-analyses in the UC and CD domain are more likely to be of poorer methodological quality, are of a greater degree of heterogeneity and less often offer a positive conclusion. The papers used to generate meta-evidence in M papers have a greater degree of corporate and government sponsorship, and are more likely to come from journals with higher impact factors.

A comprehensive review and update on the biologic treatment of adult noninfectious uveitis: part II

INTRODUCTION

Treatment of adult, noninfectious uveitis remains a major challenge for ophthalmologists around the world, especially in regard to recalcitrant cases. It is reported to comprise approximately 10% of preventable blindness in the USA. The cause of uveitis can be idiopathic or associated with infectious and systemic disorders. The era of biologic medical therapies provides new options for patients with otherwise treatment-resistant inflammatory eye disease.

AREAS COVERED

This two-part review gives a comprehensive overview of the existing medical treatment options for patients with adult, noninfectious uveitis, as well as important advances for the treatment ocular inflammation. Part I covers classic immunomodulation and latest information on corticosteroid therapy. In part II, emerging therapies are discussed, including biologic response modifiers, experimental treatments and ongoing clinical studies for uveitis.

EXPERT OPINION

The hazard of chronic corticosteroid use in the treatment of adult, noninfectious uveitis is well documented. Corticosteroid-sparing therapies, which offer a very favorable risk-benefit profile when administered properly, should be substituted. Although nothing is currently approved for on-label use in this indication, many therapies, through either translation or novel basic science research, have the potential to fill the currently exposed gaps.

Biologic therapies in inflammatory bowel disease

Inflammatory bowel disease, including its 2 entities ulcerative colitis and Crohn's disease, is a chronic medical condition characterized by the destructive inflammation of the intestinal tract. Biologics represent a class of therapeutics with immune intervention potential. These agents block the proinflammatory cascade that triggers the activation and proliferation of T lymphocytes at the level of the intestine, therefore reestablishing the balance between the pro- and anti-inflammatory messages. All 7 biologics showing clinical benefits in inflammatory bowel disease are monoclonal antibodies. The following systematic review discusses the pharmacokinetics and efficacy of the tumor necrosis factor blockers infliximab, adalimumab, certolizumab pegol, and golimumab. In addition, we describe the α4 integrin inhibitors natalizumab and vedolizumab, which are directed against cell adhesion molecules, as well as the interleukin 12/23 blocker ustekinumab.

Efficacy and safety of certolizumab pegol for Crohn's disease: a systematic review and meta-analysis

INTRODUCTION

The authors performed a systematic review and meta-analysis of data from randomized controlled trials (RCTs) to evaluate the efficacy and safety of certolizumab pegol.

METHODS

The authors searched PubMed, MEDLINE via Medscape, BioMed Central, Google Scholar, China National Knowledge Infrastructure (CNKI), the Cochrane library, and the Directory of Open Access Journals. The outcomes of interest were response and remission rates and the treatment-related toxicity rate.

RESULTS

A total of five RCTs, involving 1,891 participants, were included. The meta-analysis revealed that certolizumab significantly increased the overall (induction + maintenance therapy) response [odds ratio (OR) 1.565, 95% CI 1.056-2.321, P = 0.026] and remission rates (OR 1.626, 95% CI 1.297-2.038, P < 0.001) compared with placebo. Certolizumab significantly increased the response and remission rates when given as maintenance therapy (OR 2.171, 95% CI 1.644-2.866, P < 0.001 and OR 1.888, 95% CI 1.390-2.565, P < 0.001), but not as induction therapy (OR 1.234, 95% CI 0.912-1.671, P = 0.173 and OR 1.361, 95% CI 0.974-1.901, P = 0.071). Certolizumab (induction + maintenance therapy) did not significantly increase the treatment-related toxicity rate compared with placebo (OR 0.985, 95% CI 0.799-1.214, P = 0.887).

CONCLUSION

Certolizumab may be an efficacious treatment for Crohn's disease as maintenance therapy and appears to have a favorable safety profile.

IgG Fab fragments forming bivalent complexes by a conformational mechanism that is reversible by osmolytes

Generated by proteolytic cleavage of immunoglobulin, Fab fragments possess great promise as blocking reagents, able to bind receptors or other targets without inducing cross-linking. However, aggregation of Fab preparations is a common occurrence, which generates intrinsic stimulatory capacity and thwarts signal blockade strategies. Using a panel of biochemical approaches, including size exclusion chromatography, SDS-PAGE, mass spectrometry, and cell stimulation followed by flow cytometry, we have measured the oligomerization and acquisition of stimulatory capacity that occurs in four monoclonal IgG Fabs specific for TCR/CD3. Unexpectedly, we observed that all Fabs spontaneously formed complexes that were precisely bivalent, and these bivalent complexes possessed most of the stimulatory activity of each Fab preparation. Fabs composing bivalent complexes were more susceptible to proteolysis than monovalent Fabs, indicating a difference in conformation between the Fabs involved in these two different states of valency. Because osmolytes represent a class of compounds that stabilize protein folding and conformation, we sought to determine the extent to which the amino acid osmolyte l-proline might impact bivalent Fab complexation. We found that l-proline (i) inhibited the adoption of the conformation associated with bivalent complexation, (ii) preserved Fab monovalency, (iii) reversed the conformation of preformed bivalent Fabs to that of monovalent Fabs, and (iv) separated a significant percentage of preformed bivalent complexes into monovalent species. Thus, Fab fragments can adopt a conformation that is compatible with folding or packing of a bivalent complex in a process that can be inhibited by osmolytes.

Road to remission: a comprehensive review of therapy in uveitis

INTRODUCTION

Although uveitis remains the third leading cause of preventable blindness in the US, the care and management of patients with uveitis and ocular inflammatory disease sit poised to make evolutionary if not revolutionary changes in the years ahead. This review serves to highlight important advances in the pharmacologic options available for the treatment of uveitis and ocular inflammation.

AREAS COVERED

Advances in steroid therapy (both topical and extended delivery), updates in the clinical safety of systemic immune modulation, and the emerging therapies for uveitis and ocular inflammatory disease are some of the areas covered in this review.

EXPERT OPINION

Corticosteroids have been the mainstay in the care of patients with ocular inflammatory disorders for many years. Indeed, some physicians still use only steroids for treating inflamed eyes. However, the mission is remission of all corticosteroids in order to prevent the complications associated with long-term corticosteroid use. The goal is to achieve quiescence through aggressive use of corticosteroids to extinguish the fire and then move along to achieve steroid-free remission through immunosuppressant agents.

Current and emerging drugs for the treatment of inflammatory bowel disease

During the last decade a large number of biological agents against tumor necrosis factor-α (TNF-α), as well as many biochemical substances and molecules specifically for the medical treatment of patients with inflammatory bowel disease (IBD), have been developed. This enormous progress was a consequence of the significant advances in biotechnology along with the increased knowledge of the underlying pathophysiological mechanisms involved in the pathogenesis of IBD. However, conventional therapies remain the cornerstone of treatment for most patients. During recent years conventional and biologic IBD therapies have been optimized. Newer mesalazine formulations with a reduced pill size and only one dose per day demonstrate similar efficacy to older formulations. New corticosteroids retain the efficacy of older corticosteroids while exhibiting a higher safety profile. The role of antibiotics and probiotics has been further clarified. Significant progress in understanding thiopurine metabolism has improved the effective dose along with adjunctive therapies. Quite a large number of substances and therapies, including biologic agents other than TNF-α inhibitors, unfractionated or low-molecular-weight heparin, omega-3 polyunsaturated fatty acids, microbes and microbial products, leukocytapheresis, and other substances under investigation, could offer important benefits to our patients. In this paper we review the established and emerging therapeutic strategies in patients with Crohn's disease and ulcerative colitis.

Structural and mechanistic insight into how antibodies inhibit serine proteases

Antibodies display great versatility in protein interactions and have become important therapeutic agents for a variety of human diseases. Their ability to discriminate between highly conserved sequences could be of great use for therapeutic approaches that target proteases, for which structural features are conserved among family members. Recent crystal structures of antibody-protease complexes provide exciting insight into the variety of ways antibodies can interfere with the catalytic machinery of serine proteases. The studies revealed the molecular details of two fundamental mechanisms by which antibodies inhibit catalysis of trypsin-like serine proteases, exemplified by hepatocyte growth factor activator and MT-SP1 (matriptase). Enzyme kinetics defines both mechanisms as competitive inhibition systems, yet, on the molecular level, they involve distinct structural elements of the active-site region. In the steric hindrance mechanism, the antibody binds to protruding surface loops and inserts one or two CDR (complementarity-determining region) loops into the enzyme's substrate-binding cleft, which results in obstruction of substrate access. In the allosteric inhibition mechanism the antibody binds outside the active site at the periphery of the substrate-binding cleft and, mediated through a conformational change of a surface loop, imposes structural changes at important substrate interaction sites resulting in impaired catalysis. At the centre of this allosteric mechanism is the 99-loop, which is sandwiched between the substrate and the antibody-binding sites and serves as a mobile conduit between these sites. These findings provide comprehensive structural and functional insight into the molecular versatility of antibodies for interfering with the catalytic machinery of proteases.