Outcomes for clinical trials of food allergy treatments

The effect of subcutaneous and sublingual birch pollen immunotherapy on birch pollen-related food allergy: a systematic review

Background

Birch pollen-related food allergy (BPFA) is the most common type of food allergy in birch-endemic areas such as Western and Central Europe. Currently, there is no treatment available for BPFA. Due to the cross-reactivity between birch pollen and a range of implicated plant foods, birch pollen allergen immunotherapy (AIT) may be effective in the treatment of BPFA. In this study, we systematically evaluate the effectiveness of birch pollen-specific subcutaneous or sublingual immunotherapy in treating BPFA.

Methods

A search was performed in the PubMed, Embase, and Cochrane libraries. Studies were independently screened by two reviewers against predefined eligibility criteria. The outcomes of interest were changes in (1) severity of symptoms during food challenge, (2) eliciting dose (ED), and (3) food allergy quality of life (FA-QoL). The validity of the selected articles was assessed using the revised Cochrane risk of bias tool. We focused on studies with the lowest risk of bias and considered studies with a high risk of bias as supportive. Data were descriptively summarized.

Results

Ten studies were selected that included 475 patients in total. Seven studies were categorized into "high risk of bias" and three into "moderate risk of bias." The three moderate risk of bias studies, with a total of 98 patients, reported on severity of symptoms during challenge and on the ED. All three studies had a control group. Compared to the control group, improvement in severity of symptoms was observed during challenge in two out of the three studies and on the eliciting dose in one out of three. Only one study investigated the effect of birch pollen AIT on FA-QoL, showing that there was no significant difference between patients receiving subcutaneous immunotherapy or a placebo. Of the seven supportive studies, four had a control group and of those, three showed improvement on both severity of symptoms and ED. None of the supportive studies investigated the effect of the therapy on FA-QoL.

Conclusion

This systematic review shows that there is not enough evidence to draw firm conclusions about the effect of AIT on BPFA. Future research is warranted that uses robust clinical studies that include long-term effects, QoL, and multiple BPFA-related foods.

Patient-Reported Outcome Measures in Food and Drug Allergy

A patient-reported outcome is directly reported by the patient without interpretation of the patient's response by anyone else. It refers to the patient's health (symptoms and feelings), quality of life, or functional status associated with health care or treatment. Patient-reported outcome measures (PROMs) are defined as the tools or instruments that are used to measure patient-reported outcomes. Health-related quality of life has been the most studied psychosocial PROM in food allergy, using validated questionnaires. In drug allergy, PROMs are useful in capturing patients' experiences of potential allergic reactions, including subjective symptoms such as headache, dizziness, or fatigue. Patient-reported outcome measures can also help differentiate true allergies from side effects or other nonallergic reactions and inform decisions about drug challenges and de-labeling strategies. Ensuring the chosen tool is validated for the specific allergy context is crucial for accurate data collection. Integrating patient-reported experiences alongside traditional methods can lead to more accurate assessments and personalized care.

Core Outcome Set for IgE-mediated food allergy clinical trials and observational studies of interventions: International Delphi consensus study 'COMFA'

BACKGROUND

IgE-mediated food allergy (FA) is a global health concern with substantial individual and societal implications. While diverse intervention strategies have been researched, inconsistencies in reported outcomes limit evaluations of FA treatments. To streamline evaluations and promote consistent reporting, the Core Outcome Measures for Food Allergy (COMFA) initiative aimed to establish a Core Outcome Set (COS) for FA clinical trials and observational studies of interventions.

METHODS

The project involved a review of published clinical trials, trial protocols and qualitative literature. Outcomes found as a result of review were categorized and classified, informing a two-round online-modified Delphi process followed by hybrid consensus meeting to finalize the COS.

RESULTS

The literature review, taxonomy mapping and iterative discussions with diverse COMFA group yielded an initial list of 39 outcomes. The iterative online and in-person meetings reduced the list to 13 outcomes for voting in the formal Delphi process. One more outcome was added based on participant suggestions after the first Delphi round. A total of 778 participants from 52 countries participated, with 442 participating in both Delphi rounds. No outcome met a priori criteria for inclusion, and one was excluded as a result of the Delphi. Thirteen outcomes were brought to the hybrid consensus meeting as a result of Delphi and two outcomes, 'allergic symptoms' and 'quality of life' achieved consensus for inclusion as 'core' outcomes.

CONCLUSION

In addition to the mandatory reporting of adverse events for FA clinical trials or observational studies of interventions, allergic symptoms and quality of life should be measured as core outcomes. Future work by COMFA will define how best to measure these core outcomes.

Update on clinical research for food allergy treatment

The incidence of IgE-mediated food allergy (FA) has continued to increase over the years which places substantial burden on patient health and quality of life. With no cure for this disease, the mainstay of management has been allergen avoidance. However, there have been advancements in FA treatment in recent years with multiple clinical trials utilizing novel and innovative therapeutic strategies. A landmark event came in 2020 with the first drug approval for food allergy with the approval of a product for peanut oral immunotherapy. In addition to oral immunotherapy, different delivery systems of immunotherapy (SLIT, EPIT) are being studied in addition to probiotics, biologic agents - used as monotherapy and as an adjunct, and modified allergens has taken place with the hope to further enhance existing therapeutic options. The hope through these continued developments is for therapies to emerge that will provide a more comprehensive benefit to this patient population.

Clinical outcomes of efficacy in food allergen immunotherapy trials

PURPOSE OF REVIEW

With food allergy affecting millions of children worldwide, the consolidation of food allergen immunotherapy represents an encouraging therapeutic option, that might expand in the next few years to reach greater number of candidates. This review aims at providing a critical overview of the efficacy outcomes employed in food allergen immunotherapy trials (AIT).

RECENT FINDINGS

Understanding efficacy endpoints rely on identifying what and how these are being measured. Desensitization, as the efficacy of the therapy to increase the patient's reactivity threshold to the food during therapy, and Sustained Unresponsiveness, withholding such efficacy even if the therapy is withdrawn, are nowadays considered the main parameters of efficacy evaluation. Quality of life is a promising variable to capture food AIT impact from the patient's perspective.There is a relevant degree of heterogeneity across studies in outcomes definitions and also in oral food challenges design, the tool that is more spread to assess results, hampering study comparison.

SUMMARY

Interpreting the results of a clinical trial, and comparing data from different studies is an important task, both for the researcher and the clinician, that should be done after a careful analysis of the outcomes and the evaluation tools used.

Will Oral Food Challenges Still Be Part of Allergy Care in 10 Years' Time?

Oral food challenges (OFCs) are currently the definitive diagnostic procedure in food allergy. Their design has evolved over the decades to maximize safety, optimize convenience, and address several specific clinical questions. However, they are a resource-intensive investigation that carry a risk for severe allergic reaction in which fatal outcomes, although rare, have been reported. In this review, we explore the many roles that OFC fulfil in the clinical and research settings. We also discuss progress that has been made in developing alternative diagnostic tools and how far these have reached in offering a viable replacement to OFC in clinical practice. Finally, we discuss the ongoing importance of research OFC to improve the future diagnostic capabilities of novel diagnostic tools.

Varying Approaches to Management of IgE-Mediated Food Allergy in Children Around the World

Food allergy is a chronic disease that affects individuals of all ages and is a significant public health problem globally. This narrative overview examines clinical management strategies for IgE-mediated food allergy in children around the world to understand variations in practice. Information was drawn from clinical practice guidelines, recent research, the websites of professional and governmental bodies with expertise in food allergy, and clinical experts from a broad cross-section of geographical regions. The structure and delivery of clinical services, allergen avoidance and food labeling, and resources to support the management of allergic reactions in the community are discussed in detail. The adoption of emerging food immunotherapies is also explored. Wide variations in clinical management of food allergy were apparent across the different countries. Common themes were continuing issues with access to specialist care and recognition of the need to balance risk reduction with dietary and social restrictions to avoid unnecessary detrimental impacts on the quality of life of food allergy sufferers. Findings highlight the need for standardized presentation of practice and priorities, and may assist clinicians and researchers when engaging with government and funding agencies to address gaps.

Endpoints and Outcomes After Immunotherapy for Food Allergy: What Is Meaningful for Patients?

Multiple novel interventions for food allergy are currently at various stages of development with the goal of reducing or eliminating allergic reactions. However, the relative success of these therapeutics in achieving meaningful, long-term improvements to patients' lives is difficult to determine as there is currently very limited understanding of the degree of alignment between clinical trial efficacy endpoints and patient-centered outcomes. Furthermore, outcome measures used in clinical trials of food allergy immunotherapies vary widely, are often misinterpreted, and not necessarily consistent with what patients expect to achieve through treatment. This review aims to assist clinicians in critically interpreting outcomes reported in clinical trials and accurately communicating risks and outcomes to patients when practicing shared decision-making.

Food Allergy and Eosinophilic Gastrointestinal Diseases-The Next 10 Years

The first report of food allergy desensitization was in 1908, at least a few years before the first published description of a diagnostic test for food allergy. It has taken almost 100 years for food allergy to move from passive management of avoidance to a more proactive approach including prevention and treatment. In parallel, this has been matched by recognition of eosinophil gastrointestinal diseases, which were first described in the 1980s (although eosinophilic esophagitis was itself described in 1978). As we celebrate 10 years of The Journal of Allergy and Clinical Immunology: In Practice, we take the opportunity to look into the future and speculate how our practice may develop over the next decade.

Measuring the Impact of Food Immunotherapy on Health-Related Quality of Life in Clinical Trials

Food allergy is a common, and often lifelong, disorder with considerable negative impact on the quality of life of those affected and their families. While several promising immunotherapies for food allergy have either been approved or are in late-phase clinical trials based on demonstrated effectiveness at inducing desensitization, evidence of benefit in terms of improving patient-centered outcomes is inconsistent. Historically, health-related quality of life has not been prioritized as an endpoint in food immunotherapy trials and, even when included, findings have been undermined by methodological limitations of the measurement instruments used and issues with data interpretation. This review highlights the importance of measuring health-related quality of life as an endpoint in food immunotherapy trials and discusses the strengths and limitations of available evidence in this regard, with a focus on the appropriate use of assessment instruments and interpretation of findings. There remains much to learn regarding the impact of food immunotherapies on patient wellbeing, both during treatment and over the longer term. Our aim is to assist clinicians, researchers, policy makers and consumers in their interpretation of the existing literature, and to promote greater scientific rigor in the design and selection of outcome measurement frameworks for future studies evaluating the efficacy of immunotherapy treatments for food allergy.

Allergen immunotherapy and/or biologicals for IgE-mediated food allergy: A systematic review and meta-analysis

Background

There is substantial interest in immunotherapy and biologicals in IgE‐mediated food allergy.

Methods

We searched six databases for randomized controlled trials about immunotherapy alone or with biologicals (to April 2021) or biological monotherapy (to September 2021) in food allergy confirmed by oral food challenge. We pooled the data using random‐effects meta‐analysis.

Results

We included 36 trials about immunotherapy with 2126 mainly child participants. Oral immunotherapy increased tolerance whilst on therapy for peanut (RR 9.9, 95% CI 4.5.–21.4, high certainty); cow's milk (RR 5.7, 1.9–16.7, moderate certainty) and hen's egg allergy (RR 8.9, 4.4–18, moderate certainty). The number needed to treat to increase tolerance to a single dose of 300 mg or 1000 mg peanut protein was 2.

Oral immunotherapy did not increase adverse reactions (RR 1.1, 1.0–1.2, low certainty) or severe reactions in peanut allergy (RR 1,6, 0.7–3.5, low certainty), but may increase (mild) adverse reactions in cow's milk (RR 3.9, 2.1–7.5, low certainty) and hen's egg allergy (RR 7.0, 2.4–19.8, moderate certainty). Epicutaneous immunotherapy increased tolerance whilst on therapy for peanut (RR 2.6, 1.8–3.8, moderate certainty). Results were unclear for other allergies and administration routes.

There were too few trials of biologicals alone (3) or with immunotherapy (1) to draw conclusions.

Conclusions

Oral immunotherapy improves tolerance whilst on therapy and is probably safe in peanut, cow's milk and hen's egg allergy. More research is needed about quality of life, cost and biologicals.

Oral Immunotherapy for Food-Allergic Children: A Pro-Con Debate

The prevalence of food allergy has increased in recent years, especially in children. Allergen avoidance, and drugs in case of an allergic reaction, remains the standard of care in food allergy. Nevertheless, increasing attention has been given to the possibility to treat food allergy, through immunotherapy, particularly oral immunotherapy (OIT). Several OIT protocols and clinical trials have been published. Most of them focus on children allergic to milk, egg, or peanut, although recent studies developed protocols for other foods, such as wheat and different nuts. OIT efficacy in randomized controlled trials is usually evaluated as the possibility for patients to achieve desensitization through the consumption of an increasing amount of a food allergen, while the issue of a possible long-term sustained unresponsiveness has not been completely addressed. Here, we evaluated current pediatric OIT knowledge, focusing on the results of clinical trials and current guidelines. Specifically, we wanted to highlight what is known in terms of OIT efficacy and effectiveness, safety, and impact on quality of life. For each aspect, we reported the pros and the cons, inferable from published literature. In conclusion, even though many protocols, reviews and meta-analysis have been published on this topic, pediatric OIT remains a controversial therapy and no definitive generalized conclusion may be drawn so far. It should be an option provided by specialized teams, when both patients and their families are prone to adhere to the proposed protocol. Efficacy, long-term effectiveness, possible role of adjuvant therapies, risk of severe reactions including anaphylaxis or eosinophilic esophagitis, and impact on the quality of life of both children and caregivers are all aspects that should be discussed before starting OIT. Future studies are needed to provide firm clinical and scientific evidence, which should also consider patient reported outcomes.

Potential Biomarkers, Risk Factors and their Associations with IgE-mediated Food Allergy in Early Life: A Narrative Review

Food allergy affects the quality of life of millions of people worldwide and presents a significant psychological and financial burden for both national and international public health. In the past few decades, the prevalence of allergic disease has been on the rise worldwide. Identified risk factors for food allergy include family history, mode of delivery, variations in infant feeding practices, prior diagnosis of other atopic diseases such as eczema, and social economic status. Identifying reliable biomarkers which predict the risk of developing food allergy in early life would be valuable in both preventing morbidity and mortality and by making current interventions available at the earliest opportunity. There is also the potential to identify new therapeutic targets. This narrative review provides details on the genetic, epigenetic, dietary and microbiome influences upon the development of food allergy and synthesizes the currently available data indicating potential biomarkers. While there is a large body of research evidence available within each field of potential risk factors, there are very limited number of studies which span multiple methodological fields, for example including immunology, microbiome, genetic/epigenetic factors and dietary assessment. We recommend that further collaborative research with detailed cohort phenotyping is required to identify biomarkers, and whether these vary between at-risk populations and the wider population. The low incidence of oral food challenge confirmed food allergy in the general population, and the complexities of designing nutritional intervention studies will provide challenges for researchers to address in generating high quality, reliable and reproducible research findings.

STATEMENT OF SIGNIFICANCE

Food allergy affects the quality of life of millions of people worldwide and presents a significant psychological and financial burden for both national and international public health. Identifying reliable biomarkers which predict the risk of developing food allergy would be valuable in both preventing morbidity and mortality and by making current interventions available at the earliest opportunity. This review provides details on the genetic, epigenetic, dietary and microbiome influences upon the development of food allergy. This helps in identifying reliable biomarkers to predict the risk of developing food allergy, which could be valuable in both preventing morbidity and mortality and by making interventions available at the earliest opportunity.