Peripheral blood T-cell modulation by omalizumab in chronic urticaria patients.

Background: Chronic spontaneous urticaria (CSU) is a highly prevalent and difficult to manage cutaneous disease characterized by the presence of recurrent urticaria, angioedema, or both, for a period of 6 weeks or longer. One of the biological treatments used for patients with CSU with an autoimmune background and bad control of the disease is omalizumab, an anti-IgE monoclonal antibody. The understanding of the mechanism of action of this biological drug in CSU along with the identification of potential biomarkers of clinical response can be helpful in the personalized management of the disease. Objective: The purpose of this study was to analyze the effect of omalizumab on peripheral blood lymphocyte subpopulations in patients with CSU in order to identify potential biomarkers of treatment response. Methods: We analyzed 71 patients with CSU [33 under omalizumab and 38 under non-immunomodulatory drugs (treated with antihistamines; NID)] and 50 healthy controls. An exhaustive immunophenotyping of whole blood T-cell subpopulations, including naïve, central memory, effector memory, effector cells, Th1, Th2, and Th17 was performed by multiparametric flow cytometry. Moreover, in CSU patients, we analyzed markers of inflammation (ESR, DD, CRP), atopy (prick test, IgE quantification), and autoimmunity (anti-thyroid antibodies and indirect basophil activation test).To evaluate the clinical activity, the Urticaria Activity Score 7 (UAS 7) test was used. Results: In patients with CSU under treatment with omalizumab, there was a significant decrease in the percentage of naïve and an increase in the percentage of central memory CD4 T cells as well as a decrease in the percentage of naïve and increase in the percentage of effector CD8 T-cell subsets. Moreover, patients under treatment with omalizumab had higher percentages of Th1 and Th2 cells than patients under treatment with NID. Conclusion: The immune monitoring of T-cell subpopulations in patients with CSU starting omalizumab, may be a useful strategy to analyze treatment response in the clinical practice.

Clinical characteristics of complete responders versus non-complete responders to omalizumab, benralizumab and mepolizumab in patients with severe asthma: a long-term retrospective analysis.

BACKGROUND: Some patients with severe asthma may benefit from treatment with biologics, but evidence has been mostly collected from randomized controlled trials (RCTs), in which patients' characteristics are different from those encountered in asthma patients in the real-world setting. The aim of this study was to describe the clinical features of complete responders versus non-complete responders to long-term treatment with biologics in patients with severe asthma attended in routine daily practice. METHODS: Data of a cohort of 90 patients with severe asthma who were treated with biologics (omalizumab, benralizumab, and mepolizumab) for at least 12 months and were followed up to March 2022. Data recorded included clinical characteristics and effectiveness of treatment (exacerbation, Asthma Control Test [ACT] score, lung function, use of maintenance oral corticosteroids [mOCS]), FeNO, and blood eosinophils at baseline, at 12 months, and at the end of follow-up. Complete response is considered if, in addition to not presenting exacerbations or the use of mOCS, the ACT score was >20 and, the FEV1 >80% predicted. RESULTS: An improvement in all asthma control parameters was observed after 12 months of treatment and a mean follow-up of 55 months. After 12 months of treatment 27.2% of patients met the criteria of complete response and this percentage even increased to 35.3% at the end of follow-up. Long-term complete response was associated to better lung function with mepolizumab and omalizumab treatment and to less previous exacerbations in the benralizumab group. The main cause of not achieving a complete response was the persistence of an airflow obstructive pattern. CONCLUSIONS: This study shows that omalizumab, benralizumab, and mepolizumab improved the clinical outcomes of patients with severe asthma in a clinic environment with similar effect sizes to RCTs in the long term follow-up. Airflow obstruction, however, was a predictor of a non-complete response to biologics.

Treatment with anti-IgE and anti-IL-5 biologics significantly improved clinical outcomes in severe asthma patients.The rate of complete responders of 27.2% at 12 months even increased to 35.3% at the end of a mean follow-up of 55 months.The persistence of an airflow obstructive pattern was the main cause of the failure to achieve complete response.

Effectiveness and safety of a microcrystalline tyrosine-adjuvanted Dermatophagoides pteronyssinus allergoid immunotherapy in adult patients with allergic asthma and rhinitis: A real-life prospective observational study.

INTRODUCTION: Although clinical trials have shown the efficacy and safety of allergen-specific immunotherapy (AIT) in the treatment of allergic asthma, there is a need for real-life studies. We aimed to assess the effectiveness and safety of a microcrystalline tyrosine-adjuvanted Dermatophagoides pteronyssinus allergoid (Acarovac Plus®) in patients with house dust mite (HDM)-induced allergic asthma in a real-life study. METHODS: A subanalysis of a multicenter, prospective, observational, real-life study. Patients with rhinitis and allergic asthma caused by HDMs were assessed before AIT with Acarovac Plus® and at 6 and 12 months after this treatment. Assessment parameters were percentage of days with asthma symptoms, percentage of days on asthma medication, classification of asthma according to Spanish guidelines for the management of asthma, asthma-related quality of life (quality of life in adults with asthma questionnaire [QLAAQ]), perception of symptoms (visual analog scale [VAS]), and treatment satisfaction (treatment satisfaction questionnaire for medication [TSQM]). Safety was assessed by the number and severity of adverse reactions. RESULTS: This subanalysis included 55 patients. Treatment with Acarovac Plus® showed significant differences in the analyzed variables when the baseline visit was compared with the 12-month visit: reduction of the mean (SD) percentage of days with asthma symptoms (23.9 [9.2] vs. 5.1 [12.8]; p = .002), of the mean [SD] percentage of days on asthma medication (67.6 [42.9] vs. 45.1 [46.8]; p = .002), and of the percentage of patients with persistent asthma (78.2% vs. 38.9%; p = .009). Acarovac Plus® significantly improved asthma-related quality of life, as shown by a decrease of 1.39 points in QLAAQ score at 12 months (p < .001), and in the subjective perception of symptoms on the VAS (-3.50, p < .0001). Patients showed high treatment satisfaction according to the TSQM, and it was well tolerated. No serious adverse events were reported. CONCLUSIONS: Acarovac Plus® was effective and safe for the treatment of patients with HDM-induced allergic asthma in a real-life study.

Immunological parameters as biomarkers of response to MicroCrystalline Tyrosine-adjuvanted mite immunotherapy.

BACKGROUND: Despite the effectiveness of allergen immunotherapy (AIT), some patients are unresponsive for reasons still unknown; yet validated response biomarkers remain unavailable. OBJECTIVE: To analyze immunological parameters as biomarkers to monitor and predict clinical response to a MicroCrystalline Tyrosine-adjuvanted house dust mite (HDM) AIT in patients with allergic rhinitis (AR). METHODS: Observational, prospective, multicenter study including adult patients (aged 18-65 years) with AR, with and without asthma, sensitized to the HDM Dermatophagoides pteronyssinus (DP) and prescribed Acarovac Plus® DP 100% in the routine practice. Serum concentrations of total IgE, specific IgE, specific IgG4, IL-4, IL-5, IL-10, IL-13, and IFN-γ were compared between baseline and 12 months after AIT. The relationship between patients' baseline immunological profiles and classification as low, high, and non-responders and between their sensitization profile to DP allergens and effectiveness were analyzed. RESULTS: Of 141 patients recruited, 118 (mean [SD] age of 33.6 [9.5] years) were evaluable. One year after treatment, Der p 1-specific IgE, DP-specific IgG4, and IL-10 increased by a mean (SD) of 3.4 (13.6) kU/L (p = 0.016), 0.43 (0.55) mg/L (p < 0.0001), and 1.35 (7.56) pg/mL (p = 0.033), respectively. Non-responders showed increased baseline levels of IL-13 compared to high responders (p = 0.037). Changes in effectiveness variables between baseline and after AIT were similar regardless of the sensitization profile. CONCLUSION: Non-responsive patients to AIT showed increased baseline IL-13 concentrations, suggesting its value as prognostic biomarker. DP-specific AIT increased Der p 1-specific IgE, DP-specific IgG4, and IL-10 concentrations in patients with AR. All patients benefited from treatment regardless of their sensitization profile to major DP allergens.

Immunotheraphy in Allergic Diseases.

The prevalence of allergic diseases is increasing worldwide. It is estimated that more than 30% of the world population is now affected by one or more allergic conditions and a high proportion of this increase is in young people. The diagnosis of allergy is dependent on a history of symptoms on exposure to an allergen together with the detection of allergen-specific IgE. Accurate diagnosis of allergies opens up therapeutic options. Allergen specific immunotherapy is the only successful disease-modifying therapy for IgE-mediated allergic diseases. New therapeutic strategies have been developed or are currently under clinical trials. Besides new routes of administration, new types of allergens are being developed. The use of adjuvants may amplify the immune response towards tolerance to the antigens. In this review, we analyze different antigen-specific immunotherapies according to administration route, type of antigens and adjuvants, and we address the special case of food allergy.