Cost-Effectiveness of Food Allergy Interventions in Children: A Systematic Review of Economic Evaluations

Cost-Effectiveness of Oral Immunotherapy for Egg Allergy According to Age of Therapy Commencement

BACKGROUND

Egg oral immunotherapy (OIT) can induce desensitization or remission of egg allergy in children.

OBJECTIVE

To determine the cost-effectiveness of OIT for raw egg allergy in school-age children compared with egg avoidance, and the most cost-effective age at which to commence treatment.

METHODS

A decision-analytic Markov model estimated the health and cost outcomes of 1,000 children aged 4 years with egg allergy, comparing different ages of OIT commencement (ages 4-12, inclusive) versus ongoing egg avoidance. Years lived with egg allergy, egg tolerance or remission (natural and OIT-induced), and desensitization to egg were captured, with rates of allergic reactions and utility values assigned to each health state. Treatment effects were derived from published randomized clinical trials and meta-analyses. The main outcome was the incremental cost-effectiveness ratio (ICER) from the Australian health care payer perspective (costs in Australian dollars per quality-adjusted life-year [QALY] gained), with a 20-year time horizon, 5% annual discounting, and an AU $50,000/QALY willingness-to-pay (WTP) threshold.

RESULTS

Without OIT, 858 children attained natural resolution before age 24. Under conservative assumptions, with OIT-induced remission set at zero and 84% achieving desensitization, ICERs were below the WTP threshold for treatment commencement at age 8 or older, with the smallest ICER observed at age 12 (AU $43,233/QALY; 95% CI, 32,025-73,350). However, the cost-effectiveness of OIT was achieved at all ages (ICER less than the WTP threshold) when OIT-induced remission increased to ∼40% of treated children.

CONCLUSIONS

Based on current published evidence, the cost-effectiveness of egg OIT improves with increased age of treatment commencement. Cost-effectiveness increases when the proportion of children achieving OIT-induced remission increases.

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.

Ockham's Razor: The Application of Parsimonious Medicine in Allergy/Immunology

The spectacular advances of modern medicine have distracted clinicians from applying the age-old principles of thorough history and examination followed by only ordering tests relevant to the patient's presentation. The most obvious diagnosis is the most likely and should be addressed first. Ockham's razor, or parsimonious medicine, should be applied because plurality of diagnoses is less likely than a single explanation. Component-resolved diagnostics and biological therapies for allergy/immune-mediated diseases have been highly effective when used by specialist allergy services. However, they are accessed too easily and frequently, either before diagnostically appropriate allergy skin testing and challenge have been employed or before the reasons for poor disease control have been investigated. The current fashion to test for vitamin D insufficiency in patients with poorly controlled allergic diseases has rarely achieved benefit but significantly increased costs. There are considerable health/economic benefits from following the proven value of a thorough clinical history, examination, focused allergy/immunology testing, and the judicious use of Ockham's razor.

Prenatal Exposure to Air Pollutants Associated with Allergic Diseases in Children: Which Pollutant, When Exposure, and What Disease? A Systematic Review and Meta-analysis

This systematic review aims to identify the association between prenatal exposure to air pollutants and allergic diseases in children, focusing on specific pollutants, timing of exposure, and associated diseases. We searched PubMed, Scopus, and Web of Science for English articles until May 1, 2023, examining maternal exposure to outdoor air pollutants (PM1, PM2.5, PM10, NO, NO2, SO2, CO, and O3) during pregnancy and child allergic diseases (atopic dermatitis (AD), food allergy (FA), asthma (AT) and allergic rhinitis (AR)/hay fever (HF)). The final 38 eligible studies were included in the meta-analysis. Exposure to PM2.5 and NO2 during pregnancy was associated with the risk of childhood AD, with pooled ORs of 1.34 (95% confidence interval (CI), 1.10-1.63) and 1.10 (95%CI, 1.05-1.15) per 10 µg/m3 increase, respectively. Maternal exposure to PM1, PM2.5, and NO2 with a 10 µg/m3 increase posed a risk for AT, with pooled ORs of 1.34 (95%CI, 1.17-1.54), 1.11 (95%CI, 1.05-1.18), and 1.07 (95%CI, 1.02-1.12), respectively. An increased risk of HF was observed for PM2.5 and NO2 with a 10 µg/m3 increase, with ORs of 1.36 (95%CI, 1.17-1.58) and 1.26 (95%CI, 1.08-1.48), respectively. Traffic-related air pollutants (TRAP), particularly PM2.5 and NO2, throughout pregnancy, pose a pervasive risk for childhood allergies. Different pollutants may induce diverse allergic diseases in children across varying perinatal periods. AT is more likely to be induced by outdoor air pollutants as a health outcome. More research is needed to explore links between air pollution and airway-derived food allergies.

Cost-effectiveness analysis of probiotic peanut oral immunotherapy (PPOIT) versus placebo in Australian children with peanut allergy alongside a randomised trial

OBJECTIVE

To compared the cost-effectiveness of coadministration of a probiotic adjuvant with peanut oral immunotherapy (PPOIT) with placebo (no treatment) in children with peanut allergy.

DESIGN

Prospectively planned cost-effectiveness analysis alongside a randomised control trial.

SETTING

The Royal Children's Hospital, Melbourne, Australia.

PARTICIPANTS

56 children with peanut allergy aged 1-10 years at recruitment.

INTERVENTION

A daily dose of probiotic Lactobacillus rhamnosus CGMCC 1.3724 (NCC4007) and peanut oral immunotherapy administered for 1.5 years.

MAIN OUTCOMES MEASURES

Costs were considered from a healthcare system perspective and included costs of treatment delivery and adverse events. Effectiveness outcomes included rate of sustained unresponsiveness (SU) and quality-adjusted life years (QALYs). The cost-effectiveness of PPOIT versus placebo was analysed using patient-level data. Time horizon was 10 years from commencement of PPOIT treatment, comprising 1.5 years of treatment (actual data), 4 years of post-treatment follow-up (actual data), and 4.5 years of extrapolation thereafter (modelling).

RESULTS

Healthcare cost per patient over 10 years was higher for PPOIT compared with placebo ($A9355 vs $A1031, p<0.001). Over half of the per patient healthcare cost (53%) in the PPOIT group was attributable to treatment delivery, while the remaining cost was attributable to adverse events. Both measures of effectiveness were superior in the PPOIT group: the average SU rate over 10 years was 54% for PPOIT versus 6% for placebo (p<0.001); QALYs over 10 years were 9.05 for PPOIT versus 8.63 for placebo (p<0.001). Overall, cost per year of SU achieved was $A1694 (range $A1678, $A1709) for PPOIT compared with placebo, and cost per additional QALY gained was $A19 386 (range $A19 024, $A19 774).

CONCLUSIONS

Cost per QALY gained using PPOIT compared with no treatment is approximately $A20 000 (£10 000) and is well below the conventional value judgement threshold of $A50 000 (£25 000) per QALY gained, thus deemed good value for money ($A1= £0.5 approximately).

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry ACTRN12608000594325; Post-results.

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.

Suitability of potyviral recombinant virus-like particles bearing a complete food allergen for immunotherapy vaccines

Virus-like particles (VLPs) have been gaining attention as potential platforms for delivery of cargos in nanomedicine. Although animal viruses are largely selected due to their immunostimulatory capacities, VLPs from plant viruses constitute a promising alternative to be considered. VLPs derived from Turnip mosaic virus (TuMV) have proven to present a tridimensional structure suited to display molecules of interest on their surface, making them interesting tools to be studied in theragnostic strategies. Here, we study their potential in the treatment of food allergy by genetically coupling TuMV-derived VLPs to Pru p 3, one of the most dominant allergens in Mediterranean climates. VLPs-Pru p 3 were generated by cloning a synthetic gene encoding the TuMV coat protein and Pru p 3, separated by a linker, into a transient high-expression vector, followed by agroinfiltration in Nicotiana benthamiana plants. The generated fusion protein self-assembled in planta to form the VLPs, which were purified by exclusion chromatography. Their elongated morphology was confirmed by electron microscopy and their size (~400 nm), and monodispersity was confirmed by dynamic light scattering. Initial in vitro characterization confirmed that they were able to induce proliferation of human immune cells. This proliferative capability was enhanced when coupled with the natural lipid ligand of Pru p 3. The resultant formulation, called VLP-Complex, was also able to be transported by intestinal epithelial cells, without affecting the monolayer integrity. In light of all these results, VLP-Complex was furtherly tested in a mouse model of food allergy. Sublingual administration of VLP-Complex could effectively reduce some serological markers associated with allergic responses in mice, such as anti-Pru p 3 sIgE and sIgG2a. Noteworthy, no associated macroscopic, nephritic, or hepatic toxicity was detected, as assessed by weight, blood urea nitrogen (BUN) and galectin-3 analyses, respectively. Our results highlight the standardized production of allergen-coated TuMV-VLPs in N. benthamiana plants. The resulting formula exerts notable immunomodulatory properties without the need for potentially hazardous adjuvants. Accordingly, no detectable toxicity associated to their administration was detected. As a result, we propose them as good candidates to be furtherly studied in the treatment of immune-based pathologies.

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.

Oral Immunotherapy in Food Allergy: A Critical Pediatric Perspective

There is evidence that in children with persistent IgE-mediated food allergy (FA) to cow's milk, hen's egg, and peanut, oral allergen-specific immunotherapy (OIT) may increase the reaction threshold to the culprit food allergen(s). OIT may protect patients from the occurrence of severe reactions in case of accidental ingestion of the culprit food during treatment. Notwithstanding, many gaps are still unsolved, including safety issues, identification of predictive biomarkers, and post-desensitization efficacy. In this perspective, the use of omalizumab (Anti-IgE monoclonal antibody) has been proposed as an adjunctive treatment to OIT in order to reduce the risk of allergic reactions related to OIT. This review aims to summarize the current evidence and unmet needs on OIT in children with FA to enhance the development of longitudinal, prospective, and well-designed studies able to fill the current gaps soon.