Standardized allergen extracts for allergen immunotherapy.

Nineteen U.S. allergen extracts were standardized by the U.S. Food and Drug Administration (FDA) between 1987 and 1998, including of two house-dust mites, short ragweed, cat hair and cat pelt, seven temperate and one southern grass, and six Hymenoptera venom preparations. Relevant literature was reviewed. For each allergen, a "representative" extract was established; the potency of each representative extract was determined by measurement of the total protein content (Hymenoptera venom), radial diffusion measurement of the dominant allergen (short ragweed and cat), or, if there was no dominant allergen, then by quantitative skin testing by using the ID50EAL (intradermal dilution for 50 mm sum of erythema determines the bioequivalent allergy units) method. In vitro tests were developed to allow the manufacturer to demonstrate that each lot of its extract was statistically identical, within defined limits, to the FDA reference extract. These tests included radial immunodiffusion, competitive enzyme-linked immunosorbent assay, and isoelectric focusing. The standardized extracts offer the advantage of consistent potency from lot to lot for each manufacturer and also from manufacturer to manufacturer, and assure the presence of recognized significant allergens within the extract. Therefore, standardized extracts offer improved safety and efficacy over their nonstandardized predecessors.

The History, Present and Future of Allergen Standardization in the United States and Europe.

The topic of standardization in relation to allergen products has been discussed by allergists, regulators, and manufacturers for a long time. In contrast to synthetic medicinal products, the natural origin of allergen products makes the necessary comparability difficult to achieve. This holds true for both aspects of standardization: Batch-to-batch consistency (or product-specific standardization) and comparability among products from different manufacturers (or cross-product comparability). In this review, we focus on how the United States and the European Union have tackled the topic of allergen product standardization in the past, covering the early joint standardization efforts in the 1970s and 1980s as well as the different paths taken by the two players thereafter until today. So far, these two paths have been based on rather classical immunological methods, including the corresponding benefits like simple feasability. New technologies such as mass spectrometry present an opportunity to redefine the field of allergen standardization in the future.

Regulatory Requirements for the Quality of Allergen Products for Allergen Immunotherapy of Food Allergy.

PURPOSE OF REVIEW: Medicinal products for allergen immunotherapy (AIT) of food allergies have gained enormous momentum in recent years. With this new class of products entering marketing authorization procedures, compliance to regulatory requirements becomes a critical element. Here, an overview is provided on specific requirements and aspects concerning the quality control and manufacturing of these products. RECENT FINDINGS: Recent developments in the field of AIT for food allergies are divers, including products for oral, epicutaneous, and subcutaneous application, most notably targeting egg, milk, and peanut allergy. As the source materials for food AIT product are typically produced for food consumption and not for medicinal purposes, unique challenges arise in the manufacturing processes and controls of these medicinal products. Individual approaches are needed to assure acceptable quality, including control of relevant quantitative and qualitative characteristics. Major characteristics for quality verification include determination of protein content, total allergenic activity, and major allergen content. The applied manufacturing processes need to be established such that relevant process parameters are kept within justified limits and consistency of produced batches is assured. Allergen products for food AIT present specific challenges with respect to quality aspects that differentiate them from other commonly available AIT products. While established regulation is available and provides clear guidance for most aspects, other issues require consideration of new and individual settings relevant here. Consequently, as experience grows, respective amendments to currently available guidance may be needed.

Hymenoptera venom allergy among children in Italy: time for pediatricians to take action.

Hymenoptera venom allergy (HVA) is one of the most frequent causes of anaphylaxis following a bee, vespid or ant sting. Real-life data regarding the management of HVA in children are lacking. To address this unmet need, we carried out a survey defining the current management of HVA in children among pediatric allergists in Italy. Educational investments on the improvement of the management of pediatric patients with HVA are urgently needed, and our analysis represents a relevant instrument in targeting a roadmap with this aim. The time for pediatric allergists to take action has come, and a task force from the Rare Allergic Diseases Commission of the Italian Society of Pediatric Allergy and Immunology is working on the topic to improve pediatricians' knowledge and optimize the care of these patients.

EAACI Allergen Immunotherapy User's Guide.

Allergen immunotherapy is a cornerstone in the treatment of allergic children. The clinical efficiency relies on a well-defined immunologic mechanism promoting regulatory T cells and downplaying the immune response induced by allergens. Clinical indications have been well documented for respiratory allergy in the presence of rhinitis and/or allergic asthma, to pollens and dust mites. Patients who have had an anaphylactic reaction to hymenoptera venom are also good candidates for allergen immunotherapy. Administration of allergen is currently mostly either by subcutaneous injections or by sublingual administration. Both methods have been extensively studied and have pros and cons. Specifically in children, the choice of the method of administration according to the patient's profile is important. Although allergen immunotherapy is widely used, there is a need for improvement. More particularly, biomarkers for prediction of the success of the treatments are needed. The strength and efficiency of the immune response may also be boosted by the use of better adjuvants. Finally, novel formulations might be more efficient and might improve the patient's adherence to the treatment. This user's guide reviews current knowledge and aims to provide clinical guidance to healthcare professionals taking care of children undergoing allergen immunotherapy.

Allergen immunotherapy for pediatric asthma: current evidence and knowledge gaps.

PURPOSE OF REVIEW: The introduction of high-quality and standardized extracts for immunotherapy has renewed the interest in the treatment of pediatric allergic asthma that represents a high-prevalence disease. RECENT FINDINGS: In addition to clinical trials, several systematic reviews and metaanalyses were published, confirming overall the clinical efficacy of allergen immunotherapy in pediatric asthma. In addition, new data on the preventive effect of the treatment on asthma onset were published. Despite this, many intriguing questions emerged, in parallel to the development of knowledge. SUMMARY: Allergen immunotherapy is overall effective for the treatment of asthma in children, but a class-effect should not be claimed, rather the efficacy of each single product. According to the recent findings, the challenge for the future research will be to clarify: when to start immunotherapy in children, which are (if they exist) the predictive biomarkers for efficacy in the single individual, the magnitude of the preventive effect and the optimal duration of the treatment.

Allergen Immunotherapy in the Era of SARS-CoV-2

No disponible

Allergy immunotherapies for allergic rhinitis: systematic review and assessment of evolving quality.

Summary: Background. Heterogeneity in the design and quality of trials evaluating allergy immunotherapies (AITs) limits their comparability, making it difficult for physicians, patients, and payers to select the best treatment option. Methods. This systematic review evaluated the quality of randomised controlled trials (RCTs) of registered grass AITs using the National Institute of Health and Care Excellence checklist. Results. 17 of 44 unique RCTs (38.6%) (sample size range: 18-1,501 subjects) were subcutaneous grass immunotherapy trials and 27 (61.4%) were sublingual grass immunotherapy trials (Allergovit, 5 trials; Alutard, 8; Grazax, 13; Oralair, 6; Staloral, 8; Pollinex, 2; Phostal and Purethal, 1 each). Three trials (6.8%; all Grazax) fulfilled every quality criterion. Quality assessments revealed inconsistencies in study quality and reporting. Study quality trended towards improvement over time, particularly after 2009. Conclusions. When as-sessing grass AIT, it is important to focus not only on endpoints but also on the quality of evidence.

Understanding differences in allergen immunotherapy products and practices in North America and Europe.

Allergen immunotherapy (AIT) is thought to be clinically effective and safe in treating allergic rhinitis, asthma, and stinging insect allergy in Europe and North America. However, there are intercontinental differences in AIT therapeutic products in terms of their application and regulation. In North America unmodified standardized and nonstandardized aqueous aeroallergen extracts are approved and used almost exclusively for subcutaneous immunotherapy, whereas more product options are available in Europe, including adsorbed allergens, chemically modified allergens, or both. Both liquid extracts and tablets are approved for sublingual immunotherapy in Europe. Nevertheless, within the European Union, there are major differences in AIT products approved and used in individual countries. There are major differences in the clinical approach to subcutaneous immunotherapy in polysensitized patients; in the United States mixed extracts containing multiple aeroallergens are used, whereas European allergists preferably administer separate injections of single allergen sources or homologous groups deemed to be clinically relevant. Moreover, the regulatory approach differs between the European Union and United States. In contrast to the United States, where common allergen standards exist based on biologic activity, no common standards exist in Europe. In terms of development of new investigational products, the United States has followed the European example for phase II and III studies; no formal US Food and Drug Administration guidance has been issued.

Fast up-dosing with a birch allergoid is safe and well tolerated in allergic rhinitis patients with or without asthma.

AIM: Subcutaneous immunotherapy is effective in treating allergic rhinoconjunctivitis and asthma, but is still inconvenient when heavy schedules are used. A faster dose escalation is desirable. MATERIALS & METHODS: In this open-label, Phase II trial, 130 adults were randomized 1:1 to receive a birch pollen allergoid subcutaneous immunotherapy. Group I with four weekly injections and Group II with seven weekly injections. Safety, tolerability and immunogenicity were assessed. RESULTS: Mild-to-moderate treatment-related adverse events were reported for 57.7% of the patients (Group I: 36, Group II: 39). Tolerability was assessed by physicians and rated as 'good' or 'very good' for 55 patients in Group I (87.3%) and for 63 patients in Group II (94.0%). Levels of IgG and IgG4 increased before and after treatment significantly (p < 0.0001) in both groups. CONCLUSION: Standard versus fast dose escalation is comparable in terms of safety and tolerability.

Quality Standards for Allergen Immunotherapy Clinics in Spain: Consensus Document.

BACKGROUND AND OBJECTIVE: Allergen immunotherapy clinics (AITCs) in Spain differ widely in terms of structure, organization, resources, and portfolio of services. Therefore, it is essential to unify treatment criteria and define quality standards for the most complex AITCs. Objective: To establish a series of recommendations that make it possible to guarantee quality and safety in the administration of immunotherapy and define quality standards for the most complex AITCs. METHODS: This project began with an online survey of 65 allergy departments/units throughout Spain in 2013. Next, a 2-phase consensus process was carried out. In the first phase, 10 experts defined and agreed on the standards using the RAND/UCLA Appropriateness method; in the second, the agreements were validated by means of a 2-round Delphi consultation with 84 experts. RESULTS: Consensus was reached on minimum safety and quality criteria in the administration of allergen immunotherapy, and 2 levels of highly complex AITCs were defined: accredited AITCs and accredited AITCs with excellence. Consensus was also reached on quality standards and accreditation criteria for both levels. CONCLUSIONS: This project is pioneering in terms of its purpose (the definition of quality standards for AITCs) and of the use of structured participation techniques (combination of the RAND/UCLA and Delphi methods). It enabled the design of minimum standards for quality and safety in administering AIT, as well as quality criteria for accreditation of AITCs supported by a broad panel of experts from the Spanish Society of Allergology and Clinical Immunology.

Quality standards for allergen immunotherapy clinics in Spain: consensus document

BACKGROUND: Allergen immunotherapy clinics (AITCs) in Spain differ widely in terms of structure, organization, resources, and portfolio of services. Therefore, it is essential to unify treatment criteria and define quality standards for the most complex AITCs. OBJECTIVE: To establish a series of recommendations that make it possible to guarantee quality and safety in the administration of immunotherapy and define quality standards for the most complex AITCs. METHODS: This project began with an online survey of 65 allergy departments/units throughout Spain in 2013. Next, a 2-phase consensus process was carried out. In the first phase, 10 experts defined and agreed on the standards using the RAND/UCLA Appropriateness method; in the second, the agreements were validated by means of a 2-round Delphi consultation with 84 experts. RESULTS: Consensus was reached on minimum safety and quality criteria in the administration of allergen immunotherapy, and 2 levels of highly complex AITCs were defined: accredited AITCs and accredited AITCs with excellence. Consensus was also reached on quality standards and accreditation criteria for both levels. CONCLUSIONS: This project is pioneering in terms of its purpose (the definition of quality standards for AITCs) and of the use of structured participation techniques (combination of the RAND/UCLA and Delphi methods). It enabled the design of minimum standards for quality and safety in administering AIT, as well as quality criteria for accreditation of AITCs supported by a broad panel of experts from the Spanish Society of Allergology and Clinical Immunology

ANTECEDENTES: Las unidades de inmunoterapia (UIT) en España son muy diferentes en cuanto a estructura, organización, recursos y cartera de servicios. Por ello, resulta esencial homogeneizar criterios de actuación y definir estándares de calidad para las UIT de mayor complejidad. OBJETIVO: Establecer recomendaciones que permitan garantizar la calidad y seguridad en la administración de la inmunoterapia y definir estándares de calidad para las UIT de mayor complejidad. MÉTODOS: Proyecto iniciado (año 2013) con una encuesta on-line a 65 servicios o unidades de alergología de toda España. Posteriormente, se desarrolló un proceso de consenso en dos fases. En la primera, diez expertos definieron y consensuaron los estándares mediante el método RAND/UCLA; en la segunda, los acuerdos se validaron mediante una consulta Delphi a dos rondas con 84 expertos. RESULTADOS: Se consensuaron criterios mínimos de seguridad y calidad en la administración de inmunoterapia con alérgenos (ITA) y se definieron dos niveles de UIT de mayor complejidad: las UIT acreditadas (UITA) y las UIT acreditadas con excelencia (UITAE), consensuándose también los estándares de calidad y criterios de acreditación para ambos niveles. CONCLUSIONES: Proyecto pionero en su objetivo - definición de estándares de calidad de UIT- y en el empleo de técnicas de participación estructuradas -combinación de los métodos RAND/UCLA y Delphi-. El resultado es la definición de unos mínimos de calidad y seguridad para administrar ITA, y un conjunto de criterios de calidad para la acreditación de las UIT que cuenta con el respaldo de un amplio panel de expertos de la SEAIC

Human IgE mAbs define variability in commercial Aspergillus extract allergen composition.

Sensitization to Aspergillus species is associated with allergic respiratory diseases. Allergen immunotherapy with nonstandardized Aspergillus extracts is commonly used as therapy in these patients. Unfortunately, no method exists to measure the relevant allergen protein content in diagnostic and therapeutic extracts. Thus, there is a critical need for Aspergillus extract standardization. We hypothesized that development of Aspergillus-specific human IgE mAbs would allow for the characterization of the relevant human allergenic epitopes among currently available commercial Aspergillus fumigatus extracts. Patients with allergic bronchopulmonary mycosis were recruited from Vanderbilt University Medical Center. IgE antibody-secreting B cells were grown and immortalized using human hybridoma techniques first described here. Twenty-six human Aspergillus-reactive IgE mAbs were used as capture and detection reagents to characterize the Aspergillus allergen content of commercial extracts. We found extreme variability in the specificity and quantity of their protein targets. Just 4 mAbs reacted with all available extracts, and only 1 of 4 extracts contained the major allergen Asp f 1. This degree of variability will almost certainly affect the efficacy of these reagents when used in diagnosis and treatment. Human IgE mAbs represent an innovative tool for the evaluation of relevant human allergenic epitopes, which may assist in future development and long-term standardization of mold extracts.

Alcohol-induced respiratory symptoms improve after aspirin desensitization in patients with aspirin-exacerbated respiratory disease.

BACKGROUND: Aspirin-exacerbated respiratory disease (AERD) is characterized by chronic eosinophilic rhinosinusitis, nasal polyps, asthma, and respiratory sensitivity to aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs). In addition to sensitivity to aspirin and NSAIDs, the majority of patients with AERD have been reported to have respiratory intolerance associated with the consumption of alcohol. METHODS: A multicenter prospective cohort study was performed. Patients with AERD confirmed by aspirin challenge were eligible to participate. Those who described themselves as able to tolerate alcohol consumption were excluded. Patients underwent aspirin desensitization following endoscopic sinus surgery. A questionnaire was distributed to patients before and after desensitization to determine pre-desensitization and post-desensitization symptoms associated with alcohol ingestion. RESULTS: Forty-five patients were enrolled and 37 patients completed the study. The most common pre-desensitization symptoms were nasal congestion (95.6%), rhinorrhea (46.7%), and wheezing (40%). Improvement in the ability to tolerate alcohol was noted in 86.5% of participants (95% confidence interval [CI], 75.5% to 97.5%) and 70.3% of participants (95% CI, 55.5% to 85.0%) described desensitization to be "very helpful" or "extremely helpful" for their ability to tolerate alcohol. CONCLUSION: The majority of patients with AERD who experience respiratory symptoms with alcohol consumption describe improvement in this domain following aspirin desensitization.

Treatment strategy of allergic rhinitis in the face of modern world threats.

Allergic rhinitis (AR) is the most common form of allergy, which - as epidemiological research has shown - applies to nearly 25% of the population. AR significantly affects the quality of life of the patient, and the more severe the disease, the greater the risk of developing bronchial asthma. One of the factors affecting the severity of symptoms and the degree of their control is air pollution. In some patients, despite proper treatment, persistence or only partial remission of symptoms (uncontrolled allergic rhinitis) is observed. This can lead to an increase in comorbidities - inflammation of the paranasal sinuses, otitis media and asthma - both in children and in adults. The treatment of allergic rhinitis, in accordance with the standards, consists in: education of the patient, elimination of the allergen from the environment and factors intensifying the course of the disease, selection of proper pharmacotherapy and specific allergen immunotherapy. Many factors influence the selection of the antihistamine used, e.g., the opportunity of safe increase of the dosage.

Nationwide questionnaire-based survey of oral immunotherapy in Japan.

BACKGROUND: Clinical trials on oral immunotherapy (OIT) have been increasing for nearly a decade; however, several national guidelines do not recommend OIT as a standardized procedure. The aim of this study was to obtain insights into the current use and practice of OIT in Japan. METHODS: A first questionnaire was mailed to 524 training and teaching facilities of the Japan Pediatric Society. The first survey requested information on the implementation of OIT, whereas the second survey aimed to gather more detailed information on OIT, such as its safety. RESULTS: In total, 360 facilities (69%) responded to the survey; among them, 102 (28%) provided OIT to 7973 patients [1544 received OIT while hospitalized (inpatient OIT), whereas 6429 received OIT without hospitalization (outpatient OIT)]. Approval for OIT was obtained from an ethics committee or institutional review board in 89% and 31% of facilities for inpatient and outpatient OIT, respectively. In inpatient OIT, immediate allergic reactions requiring treatment occurred in 68% of patients while hospitalized, and in another 56%, following discharge. In contrast, 11% of patients developed immediate allergic reactions in outpatient OIT. Adrenaline injections at home were required in 2%. Sixteen patients developed adverse reactions other than immediate allergic reactions, among which eosinophilic gastroenteritis was most common. CONCLUSIONS: OIT is widely provided not only as clinical research but also as general practice in Japan. However, because there is a high risk of developing anaphylaxis at home, OIT should be conducted carefully as in a clinical research setting taking safety into consideration.

National clinical practice guidelines for allergen immunotherapy: An international assessment applying AGREE-II.

BACKGROUND: Since 1988, numerous allergen immunotherapy guidelines (AIT-GLs) have been developed by national and international organizations to guide physicians in AIT. Even so, AIT is still severely underused. OBJECTIVE: To evaluate AIT-GLs with AGREE-II, developed in 2010 by McMaster University methodologists to comprehensively evaluate GL quality. METHODS: Allergist, from different continents, knowledgeable in AIT and AGREE-II trained were selected into the project team. The project received methodologists' guidance. AIT-GLs in any language were sought from 1980 to 2016; AIT-GLs were AGREE II-evaluated by at least 2 team members, independently; discrepancies were resolved in a second round, by team discussion or methodologists' consulting. RESULTS: We found 31 AIT-GLs (15 post-2010), ranging from local consensus reports to international position papers (EAACI, AAAAI-ACAAI, WAO). Pre-2010 GLs scored 1.6-4.6 (23%-67%) and post-2010 GLs scored 2.1-6 (30%-86%), on a 7-point Likert scale. The highest scores went to: German-Austrian-Swiss (6.0), Mexican (5.1), and the AAAAI/ACAAI AIT-GL (4.7). These were also the only 3 GLs that received "yes" of both evaluators to the item: "I would recommend this GL for use." The domains of "Stakeholder involvement" and "Rigor of Development" only scored 3/7, and "Applicability" scored the lowest. Strikingly, newer GLs only scored clearly better in "Editorial independence" and "Global evaluation." CONCLUSIONS: In AIT-GLs, there is still a lot of room for improvement, especially in domains crucial for the dissemination. For some GLs, the "Scientific rigor" domain flawed. When resources are limited, transculturizing a high-quality GL might be preferable over developing a GL from zero. Our study and AGREE-II could help to select the best candidate. CLINICAL IMPLICATIONS: We here evaluate allergen immunotherapy guideline (AIT-GL) quality. Only high-quality AIT-GLs should be consulted for AIT management decisions. In low-resource settings, transculturization of these is preferred over developing low-quality guidelines.