Advances in anti-IgE therapy

Predictive biomarkers for response to omalizumab in patients with severe allergic asthma: a meta-analysis

BACKGROUND

Predicting omalizumab treatment response has been a challenge and significant aspect for selecting suitable severe allergic asthma patients for omalizumab use.

OBJECTIVE

To determine which domains of pretreatment baseline characteristics predict omalizumab treatment response among asthmatic patients.

METHODS

Electronic bases were searched for eligible studies that reported potential biomarkers that could predict omalizumab responsiveness and efficacy. Patients who accepted omalizumab treatment were stratified into responders and non-responders. WMD, OR, and their 95%CI were used to access the differences between those omalizumab receivers. Sensitivity analysis and subgroup analysis were conducted for potential heterogeneity.

RESULTS

A total of 41 studies evaluating efficacy predictors of omalizumab were included in this meta-analysis. The pooled results showed that omalizumab responders had significantly younger age in the adult subgroup, higher pretreatment total serum IgE level, percent predicted FEV₁ and FeNO than that non-responder. We further confirmed that higher blood eosinophil counts and total serum IgE levels are useful markers for selecting asthma patients who may benefit more from omalizumab.

CONCLUSIONS

Pre-treatment blood eosinophil counts and total serum IgE level can be a useful efficacy predictor in selecting allergic asthma patients for omalizumab treatment.

Successful treatment of refractory status asthmaticus with omalizumab: a case report

Refractory status asthmaticus is the cause of rare cases of in-hospital death due to acute bronchial asthma. The most severe cases unresponsive to first, second and next line treatment may be fatal despite aggressive organ support with invasive ventilation and extracorporeal membrane oxygenation. Omalizumab, a humanized recombinant monoclonal anti-IgE antibody, is an approved add-on biological treatment for severe asthma. However, it is not indicated in an acute setting. Here, we report the case of a young patient with status asthmaticus fully dependent on extracorporeal membrane oxygenation refractory to any therapy for six days, who was successfully treated with omalizumab.

Anti-IgE for the Treatment of Chronic Urticaria

Urticaria and angioedema are very common. Management of chronic urticaria subtypes, which usually persist for many years, is challenging. Recent years have demonstrated that targeting IgE with antibodies provides a safe and efficient treatment approach. Whilst several anti-IgE antibodies have been developed, omalizumab is currently the only one approved for use. International and national guidelines recommend its use after failure of antihistamines at standard and increased dose. Whilst not yet approved, many new anti-IgE approaches are currently being investigated in pre-clinical studies or clinical trials. This non-systematic focused review summarizes current knowledge of omalizumab and other anti-IgE biologics in chronic urticaria using data extracted from PubMed, Google Scholar and clinical trial databases, clinicaltrials.gov and clinicaltrials.eu. For adults, there is good evidence from randomized clinical trials and real-world data that symptomatic treatment with omalizumab is efficacious and safe in chronic spontaneous urticaria (CSU), whereas evidence in chronic inducible urticaria (CINDU) and special populations is limited. Easy-to-use tools to identify non-responders and predict the required duration of treatment have not been established yet. Phase 2 b results of ligelizumab have not only demonstrated efficacy and safety but also superiority to omalizumab. Indeed, there is preliminary evidence that omalizumab non- or partial responders benefit from ligelizumab. Whereas further development of quilizumab was discontinued, other approaches, eg UB-221 or DARPins are under investigation. Anti-IgE treatment with omalizumab represents a landmark in the treatment of chronic urticaria, with and without angioedema, and there is light on the horizon suggesting success may come with various next-generation anti-IgE approaches.

Future perspective: biologic agents in patients with severe COVID-19

The SARS-CoV-2 is a β-CoV, which is enveloped by non-segmented positive-stranded RNA virüs. When β-CoV infects the respiratory tract, it can cause mild and/or severe acute respiratory syndrome (SARS) with consequent release of cytokines/mediators, including interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8 (CXCL8), IL-10, IP10, IL-12, IL-13, IL-17, IL-33, IL-25, IL-37, IL-38, GCSF, GM-CSF, HGF, IP-10, MCP-1, MIP-1α (also known as CCL3), IFN-γ, IFN-α, TRAIL, MCSF, and TNF-α. Our hypothesis of writing this article can be summarized as; if the monoclonal antibody (mAb) administered by us does not inhibit the immune response for the β-CoV and inhibits uncontrolled-adaptive/hyperimmune responses (also called cytokine storm) on endothelium level, then it may cause severe coronavirus disease 2019 (COVID-19). Anakinra is a human IL-1 receptor antagonist. By inhibiting IL-1α/IL-1β competitively from binding to the IL-1 type-I receptor, anakinra, neutralizes the activity that pertains to these key mediators of autoinflammatory and/or immune processes. Tocilizumab is a blocker of IL-6R that can effectively block IL-6 signal transduction pathway. Omalizumab that binds to the CH3 domain is near to the binding site for the high-affinity IgE Fc receptors type-I of human IgE. Myocardial, lung and hepatorenal injury in patients with COVID-19 could be due to cytokine storm, hypoxic injury, or/and direct endothelial/vascular injury. We propose combination of mAbs with remdesivir and/or favipiravir in severe COVID-19 cases, such as septic shock, acute respiratory deficiency syndrome, and/or multiple organ failure. Finally, we highlight the therapeutic mAbs that target patients with severe COVID-19.

Human(ized) monoclonal antibodies in atopic patients - state of the art

Asthma is an important chronic disease affecting a lot of people worldwide. Treatment options for asthma like biological agents are being developed more frequently nowadays. Despite a lot of treatment options, some patients still remain symptomatic. As more and more practitioners choose treatment with biologic agents as a convenient way of therapy, biologic agents and other valuable methods must be discovered in order to cope with a growing number of treatment agents. This manuscript emphasizes on new generation monoclonal human(ized) antibodies in asthmatics and off-label use . The first developed biologic agent is the anti-immunoglobulin E monoclonal antibody called omalizumab. Currently it is an approved treatment option for asthma.

Anti-IgE Significantly Changes Circulating Interleukin-25, Vitamin-D and Interleukin-33 Levels in Patients with Allergic Asthma

BACKGROUND

Multi-center, randomized-controlled trials and observational studies have demonstrated that, in severe asthmatic patients receiving omalizumab treatment, the frequency of exacerbations, the number of urgent adverse events, and the need for oral steroids tend to decrease.

MATERIALS AND METHODS

This study included a total of 32 patients. The patients were divided into two groups as Group IA (pre-omalizumab) and Group IB (post-omalizumab). Serum IL-25 and IL-33 levels were measured and the number of emergency admissions, length of hospitalization (day), Asthma Control Test (ACT) scores, eosinophil cationic protein (ECP), and fractional exhaled nitric oxide (FeNO) value were analyzed.

RESULTS

ACT and FeNO values increased after omalizumab treatment, while IL-33, IL-25 levels decreased after the completion of omalizumab treatment. Furthermore, there was a weak, positive, and significant relationship between the changes in the ECP levels and IL-33 levels (r=0.38, p=0.03).

CONCLUSION

To the best of our knowledge, this is the first study to compare circulating IL-25 and IL-33 levels with specific IgE synthesis in the literature. Multivariate correlation analysis showed that the changes in serum IL-33 levels were significantly correlated with the changes in the mite sIgE levels and length of hospital stay (Fmodel=11.2, p=0.01, r2=0.45). On the other hand, there was no significant relationship between the other variables and changes in the IL-25 levels.

Targeting histone-acetyltransferase Tat-interactive protein 60 inhibits intestinal allergy

BACKGROUND

The overproduction of IgE plays a critical role in the pathogenesis of allergy; the mechanism is unclear. Histone-acetyltransferase (HAT) activities are required in gene transcription of a large number of molecules in the immune system of the body.

OBJECTIVES

This study tests a hypothesis that HAT Tat-interactive protein 60 (Tip60) plays an important role in the initiation of IgE-mediated allergy.

METHODS

The effects of Tip60 on regulating IgE expression were assessed with B cells. An intestinal allergy mouse model was developed to assess the role of Tip60 in the induction of IgE-mediated allergic inflammation.

RESULTS

High levels of Tip60 were observed in the peripheral B cells of patients with FA. Tat-interactive protein 60 (Tip60) was required in the expression of IgE and IgG1 in B cells by inducing the chromatin remolding at the gene locus, in which histone acetylation, signal transducer and activator of transcription 6 (STAT6), and nuclear factor-κB at the locus of Iε promoter were markedly increased. Blocking Tip60 significantly attenuated the allergic inflammation in the mouse intestinal mucosa.

CONCLUSIONS

Tat-interactive protein 60 (Tip60) plays an important role in the induction of IgE in B cells. Blocking Tip60 inhibits the allergic inflammation in the intestine, suggesting Tip60 inhibitor may be a potential anti-allergy drug.

Possible therapeutic role of IgE blockade in irritable bowel syndrome

Omalizumab is a humanized monoclonal antibody that binds to the high-affinity type-I IgE Fc receptors on mast cells (MCs) and basophils, inhibiting the IgE immune pathway. Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder, and dysregulation of the immune system likely contributes to its etiology and/or symptomatology. Colonic biopsies from patients with IBS demonstrate considerable increase in the number of degranulating MCs releasing histamine in proximity to nerves, and this event may underlie the common IBS symptom of abdominal pain. Pharmacologic control of MC activation and mediator release is a current area of active interest in the field of IBS research. Recently, we and Pearson et al described 2 cases of patients with IBS with diarrhea (IBS-D) showing positive clinical response to omalizumab. In both cases, the female patients had severe, long-lasting IBS-D and achieved an almost complete resolution of IBS symptoms. Both patients were also able to discontinue all IBS medications after commencing the anti-IgE therapy. For both patients, the omalizumab treatment showed a relatively rapid onset of action, resembling the efficacy observed in and previously reported for patients with chronic spontaneous urticaria. In this Editorial, we discuss the possible biological mechanisms that may underlie the clinical efficacy of omalizumab in IBS. We suggest that there is a need for a well-designed prospective study to investigate the therapeutic effects of anti-IgE in IBS.

Levofloxacin Induced Toxic Epidermal Necrolysis: Successful Therapy with Omalizumab (Anti-IgE) and Pulse Prednisolone

BACKGROUND Toxic epidermal necrolysis (TEN) is characterized by widespread erythematous and bullous lesions on the skin. Nowadays, considerable progress has been made in the understanding of its pathogenesis. Immunologically it is similar to graft-versus-host disease. Therefore, we may propose that TEN is a disorder of cell-mediated immunity. CASE REPORT Our patient was a 74-year-old white female who had pneumonia and was positive for hepatitis C virus (HCV), and who had been on levofloxacin therapy. After the first levofloxacin dose, erythematous dusky red macules occurred on her extremities and trunk, and on the following day, confluent purpuric lesions tended to run together over 85% of her body. Her biopsy results indicated TEN. Laboratory testing for serum ECP (eosinophil cationic peptide) and serum immunoglobulin (Ig) levels were performed, and blister fluid was investigated. The patient responded positively to omalizumab treatment and after treatment laboratory tests revealed decreased high sensitive CRP, ECP, IgG1, IgG2, IgG3, IgG4, IgA, and IgM levels. CONCLUSIONS To the best of our knowledge, this is the first case of a patient with HCV who developed cutaneous adverse drug reaction on levofloxacin medication and recovered with omalizumab treatment. This is the first documentation of omalizumab treatment of a TEN patient.

Flagellin modulates IgE expression in B cells to initiate food allergy in mice

The initiation mechanism of IgE expression has not been fully understood. Flagellin (FGN) is an important microbial factor in the regulation of immune responses in the intestine. This study tests a hypothesis that FGN plays a crucial role in the isotype switching of IgE in B cells and the initiation of food allergy. In this study, the expression of IgE in B cells was analyzed by real time RT-PCR, Western blotting and chromatin immunoprecipitation. A mouse model was developed to assess the role of Toll like receptor-5 in the development of IgE-mediated allergic reaction in the intestinal mucosa. The results showed that exposure to FGN suppressed the expression of Bcl6 in B cells via increasing the levels of histone deacetylase (HDAC) 7; the latter up regulated the levels of methylated H3K9 and H3K27, down regulated RNA polymerase II and STAT3 (signal transducer and activator of transcription 3) at the Bcl6 promoter locus. Exposure to FGN and IL-4 markedly increased the expression of IgE in B cells via activating p300, H3K4, Pol II and STAT6 at the IgE promoter locus. As compared with the sensitized wild mice, the sensitized TLR5-deficient mice showed no detectable OVA-specific IgE in the serum; mast cells in the intestinal mucosa were not activated, no apparent allergic symptoms were evoked after the specific antigen challenge. In conclusion, FGN facilitates the initiation of food allergy in mice by triggering IgE transcription in B cells in a Th2 polarization environment via activating HDAC7 and suppressing Bcl6 expression.

Humoral immune factors and asthma among American Indian children: a case-control study

Background

Asthma is recognized as intimately related to immunologic factors and inflammation, although there are likely multiple phenotypes and pathophysiologic pathways. Biomarkers of inflammation may shed light on causal factors and have potential clinical utility. Individual and population genetic factors are correlated with risk for asthma and improved understanding of these contributions could improve treatment and prevention of this serious condition.

Methods

A population-based sample of 108 children with clinically defined asthma and 216 control children were recruited from a small community in the northern plains of the United States. A complete blood count, high sensitivity C-reactive protein, total IgE and specific antibodies to 5 common airborne antigens (CAA), in addition to basic demographic and anthropomorphic data were obtained. Logistic regression was primarily used to determine the association between these humoral factors and risk of asthma.

Results

The body mass index (BMI) of those with asthma and their total leukocyte counts, percentage of eosinophils, and levels of total IgE were all greater than corresponding control values in univariate analysis. The presence of detectable, specific IgE antibodies to five common airborne antigens was more likely among cases compared with controls. In multivariate analysis, total IgE was independently associated with asthma; but not after inclusion of a cumulative measure of specific IgE sensitization.

Conclusion

Many previously reported associations between anthropomorphic and immune factors and increased risk of asthma appear to be also present in this American Indian population. In this community, asthma is strongly associated with sensitization to CAA.

A case of netherton syndrome: successful treatment with omalizumab and pulse prednisolone and its effects on cytokines and immunoglobulin levels

CONTEXT

Netherton syndrome (NS) is associated with the mutation in the SPINK5 gene, which codes LEKTI (lymphoepithelial Kazaltype related inhibitor), a serine protease inhibitor. As a result of aging coupled with immune deficiency, clinical symptoms may vary.

METHODS

The patient was presented to our clinic with sparse and brittle hair along with pruritic, erythematous and scaling cutaneous lesions. The patient underwent a clinical examination and laboratory analyzes. Based on the clinical and laboratory findings, the patient was diagnosed with NS. Moreover, CRP, Complement-3 (C3), C4 IL-4, IL-5, IL-1β and IL-17A levels of serum were investigated as an apoptotic marker and a negative marker for inflammation.

RESULTS

Having undergone omalizumab treatment and a short-term (4 months) later, he had a decreased IgE, Ig G, prolactin, CRP, IL-4, IL-5, IL-1β and IL-17A levels. The IgA, IgM and C3, C4 levels were insignificant between before and after Omalizumab treatment.

CONCLUSION

To the best of our knowledge, this is the first time that an association between omalizumab and NS was documented. In conclusion allergic skin symptoms (pruritus, erythema and desquamation) and mucosal symptoms decreased in the patient.

Urticaria as initial finding of a patient with carcinoid tumor

BACKGROUND

Typical carcinoid syndrome is characterized by flushing, abdominal pain and diarrhea and occurs in <10 % of carcinoid tumor patients. Very rarely, initial signs include skin manifestations. Our purpose is to highlight cutaneous manifestations in the diagnosis and assessment of a patient with atypical manifestation of type I gastric carcinoid tumor.

CASE PRESENTATION

A 50-year-old woman presented with anemia, chronic urticaria and angioedema. Urticaria was triggered principally by seafood and appeared in the first hour after. Urticaria Activity Score 7 was 24, and quality of life (CU-Q2oL) was 3.61. P. Laboratory findings showed anemia, diminished iron, ferritin, and vitamin B12, with increased gastrin and anti-parietal cell antibody levels. 15 gastric carcinoids 5 mm in diameter were observed in the greater curvature of the stomach during gastric endoscopy and confirmed by biopsy, suggesting that this patient had type I gastric carcinoids. Four additional tumors were found in the small intestine upon examination via video capsule. Endoscopic argon plasma therapy was performed. The patient experienced definitive improvement in quality of life and urticaria activity score.

CONCLUSION

This patient, whose principal symptoms were anemia, urticaria and angioedema, was found to have atypical carcinoid syndrome, with tumors located in the stomach. Allergists, immunologists, internists and primary care physicians should consider the possibility of neuroendocrine malignancies, specifically type I carcinoid tumors, when evaluating patients with urticaria, and consider screening patients with chronic urticaria for elevated anti-parietal cell antibody levels.