Conflicting verdicts on peanut oral immunotherapy from the Institute for Clinical and Economic Review and US Food and Drug Administration Advisory Committee: Where do we go from here?

Transitioning peanut oral immunotherapy to clinical practice

Peanut allergy is on the rise in industrialized countries, affecting 1%–4.5% of children and generally persisting into adulthood. It is associated with a risk of severe anaphylaxis and is one of the major causes of food allergy-induced deaths. Health-related quality of life is significantly impaired for patients and affected families due to food restrictions attributable to omnipresent precautionary allergen labeling, constant risk of potentially life-threatening reactions, and limitation of social activities. Oral immunotherapy (OIT) has emerged as a valid treatment option for patients with IgE-mediated peanut allergy, with randomized controlled trials and real-life studies showing a high rate of desensitization and a favorable safety profile, especially in young children. Ultimately, the decision to initiate peanut OIT relies on a multidisciplinary shared decision-making process, involving open, personalized and evidence-based discussions with patients and their caregivers.

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 children with a high-threshold peanut allergy

BACKGROUND

Between 25% and 30% of children with peanut allergy (PA) have a relatively high-threshold peanut allergy (HTPA), with a single maximal tolerated dose (SMTD) higher than 100 mg of peanut protein (PP). However, this threshold may decrease with time, age, exercise, illness, sleep deprivation, and other covariates.

OBJECTIVE

To explore the feasibility of a simplified oral immunotherapy (OIT) protocol in a group of children with HTPA.

METHODS

Children with PA with an SMTD higher than 100 mg were placed on a 40-week OIT protocol of either 300 mg/d of PP or 100 mg/d for 20 weeks followed by 300 mg/d for 20 weeks. A repeat open peanut food challenge was performed after 40 weeks of treatment and at a 6-month follow-up visit. After the 40-week challenge, all children received a maintenance dosage of 2 gPP 3 times a week.

RESULTS

A total of 28 children with HTPA were enrolled, with 56% boys, 89% younger than 6 years old, and a mean SMTD of 304 mg (95% confidence interval 229-378). All were placed on the described OIT protocol. Overall, 2 children were not compliant and 3 had allergic reactions at home on the dose previously tolerated in clinic, 23 completed the 40-week protocol, and all were able to consume 2 g of PP. The mean tolerated dosage at the 6-month follow-up was 8 g. This enabled most children age-appropriate dietary inclusion of peanut-containing products.

CONCLUSION

In children with HTPA, a simple, fixed-dose OIT can be both safe and efficacious.

From Allergen Molecules to Molecular Immunotherapy of Nut Allergy: A Hard Nut to Crack

Peanuts and tree nuts are two of the most common elicitors of immunoglobulin E (IgE)-mediated food allergy. Nut allergy is frequently associated with systemic reactions and can lead to potentially life-threatening respiratory and circulatory symptoms. Furthermore, nut allergy usually persists throughout life. Whether sensitized patients exhibit severe and life-threatening reactions (e.g., anaphylaxis), mild and/or local reactions (e.g., pollen-food allergy syndrome) or no relevant symptoms depends much on IgE recognition of digestion-resistant class I food allergens, IgE cross-reactivity of class II food allergens with respiratory allergens and clinically not relevant plant-derived carbohydrate epitopes, respectively. Accordingly, molecular allergy diagnosis based on the measurement of allergen-specific IgE levels to allergen molecules provides important information in addition to provocation testing in the diagnosis of food allergy. Molecular allergy diagnosis helps identifying the genuinely sensitizing nuts, it determines IgE sensitization to class I and II food allergen molecules and hence provides a basis for personalized forms of treatment such as precise prescription of diet and allergen-specific immunotherapy (AIT). Currently available forms of nut-specific AIT are based only on allergen extracts, have been mainly developed for peanut but not for other nuts and, unlike AIT for respiratory allergies which utilize often subcutaneous administration, are given preferentially by the oral route. Here we review prevalence of allergy to peanut and tree nuts in different populations of the world, summarize knowledge regarding the involved nut allergen molecules and current AIT approaches for nut allergy. We argue that nut-specific AIT may benefit from molecular subcutaneous AIT (SCIT) approaches but identify also possible hurdles for such an approach and explain why molecular SCIT may be a hard nut to crack.

Emerging developments in the forefront of peanut oral immunotherapy

PURPOSE OF REVIEW

Despite the COVID-19 pandemic, progress continued in the field of peanut oral immunotherapy over the past 12 to 18 months. Of importance, the first oral immunotherapy product for the treatment of peanut allergy was approved by the US Food and Drug Administration in January 2020.

RECENT FINDINGS

Suggested modifications to the practice of oral immunotherapy, some of which may have lasting impacts, were circulated as a result of the pandemic. New advances in pathophysiology, sustained unresponsiveness, quality of life, safety, and cost effectiveness were also published.

SUMMARY

During 2020, COVID-19 influenced the daily practice of allergy and immunology, with peanut oral immunotherapy being no exception. However, clinicians now have a FDA-approved treatment option for peanut allergy in children, a welcome development for a difficult disease. Future research is needed to clarify several knowledge deficits surrounding the best use of peanut OIT.

Oral immunotherapy in food allergies: A practical update for pediatricians

Food oral immunotherapy (OIT) is a promising treatment for persistent and severe food allergies (FAs) in children, but also for accelerating tolerance to cow's milk and cooked egg in young children. In the near future, pediatricians will increasingly encounter severely allergic children undergoing FA-OIT. FA-OIT consists in daily ingestion of increasing doses of the allergen during the up-dosing phase, and ingestion of a constant dose during the maintenance phase. The global aim is to increase the reactive threshold of allergic patients, and finally enable them to ingest a target quantity of allergen without any reaction throughout the treatment (desensitization). Many studies showed the efficacy of FA-OIT in desensitization, and some of them in sustained unresponsiveness. This corresponds to tolerance after FA-OIT discontinuation, especially for cow's milk and hen's egg allergy. However, there is an ongoing debate about the safety of the treatment. Side effects are frequent, notably aversion to the allergen and oral syndromes as well as systemic allergic symptoms. These reactions occur mainly during the up-dosing phase and become less frequent with time, but they are common causes of FA-OIT discontinuation. Patients and their families must be trained to manage these reactions at home. Long-term side effects can also occur, such as eosinophilic esophagitis. Pediatricians play an important role in maintaining patient motivation; they also provide knowledge on possible allergic reactions and the reactogenic cofactors (mainly fever and viral infection, anti-inflammatory intake, physical activity), and refer the patient to the relevant specialists in the case of long-term care. Other routes of administration for food immunotherapy (epicutaneous and sublingual) and different adjuvant treatments (probiotics, anti-IgE molecule) are currently under study. This will allow us to improve the efficacy of immunotherapy and reduce the risk of any side effects, in order to provide a more favorable risk-benefit ratio.

Practical challenges in oral immunotherapy resolved through patient-centered care

Oral immunotherapy (OIT) is now widely recognized as a valid option for the management of IgE-mediated food allergies. However, in real-life practice, OIT can lead to a variety of unique situations where the best course of action is undetermined. In patient-centered care, individual patient preferences, needs and values, should guide all clinical decisions. This can be achieved by using shared-decision making and treatment customization to navigate areas of uncertainty in a way that is responsive to patient’s needs and preferences. However, in the context of OIT, lack of awareness of potential protocol adaptability or alternatives can become a barrier to treatment personalization. The purpose of this article is to review the theoretical bases of patient-centered care and shared decision-making and their practical implication for the patient-centered delivery of OIT. Clinical cases highlighting common challenges in real-life OIT practice are presented along with a discussion of potential personalized management options to be considered. While the practice of OIT is bound to evolve as additional scientific and experiential knowledge is gained, it should always remain rooted in the general principles of patient-centered care.

Integrating oral immunotherapy into clinical practice

In 2020, the first food allergy treatment, an oral immunotherapy (OIT) product for peanut allergy, was approved by the Food and Drug Administration, and a peanut epicutaneous immunotherapy patch was under review. As food allergy therapies become available and widespread, allergy offices will need to adjust practices to be able to offer their patients these new treatments. OIT is an intensive therapy that requires commitment from patients and their families, and open communication with the practice is paramount. OIT may not be the right therapy for every patient, and although identifying good candidates is still an area rich for research opportunity, experience from cohorts and clinical trials provides some insight. It is important to understand the scope of practice for each member of the OIT team based on state regulations for a particular location. Staffing and space will likely dictate how many patients at an individual office could be on active OIT at one time. Emergency medications, supplies, and protocols must be in place. Screening, scheduling, visit procedures, monitoring, home dosing, dose modifications, safety precautions, adverse reactions, and maintenance will be addressed in this article. Finally, adjunct therapies under investigation will be reviewed.

Past, present, and future of allergen immunotherapy vaccines

Allergen-specific immunotherapy (AIT) is an allergen-specific form of treatment for patients suffering from immunoglobulin E (IgE)-associated allergy; the most common and important immunologically mediated hypersensitivity disease. AIT is based on the administration of the disease-causing allergen with the goal to induce a protective immunity consisting of allergen-specific blocking IgG antibodies and alterations of the cellular immune response so that the patient can tolerate allergen contact. Major advantages of AIT over all other existing treatments for allergy are that AIT induces a long-lasting protection and prevents the progression of disease to severe manifestations. AIT is cost effective because it uses the patient´s own immune system for protection and potentially can be used as a preventive treatment. However, broad application of AIT is limited by mainly technical issues such as the quality of allergen preparations and the risk of inducing side effects which results in extremely cumbersome treatment schedules reducing patient´s compliance. In this article we review progress in AIT made from its beginning and provide an overview of the state of the art, the needs for further development, and possible technical solutions available through molecular allergology. Finally, we consider visions for AIT development towards prophylactic application.

Emerging Therapies for Peanut Allergy

Peanut allergy (PA) is a food allergy that causes an IgE-mediated type I hypersensitivity reaction. PA has become an increasing public health burden, with 2% of American children reported to have this condition in 2010. Current guidelines recommend allergen avoidance, patient education, and administration of H1 antihistamines, β2-agonists, or epinephrine based on the severity of reaction. In this review article, emerging therapies for PA are evaluated for their potential role in treating PA. Oral, epicutaneous, and sublingual immunotherapies have completed clinical trials with promising efficacy. In particular, Palforzia (AR101) is an oral immunotherapy that received Food and Drug Administration (FDA)-approval in January 2020 and Viaskin Peanut is an epicutaneous immunotherapy with an anticipated FDA decision date by August 5, 2020. Furthermore, adjuvant combinations with either probiotics or anti-IgE receptor antagonists have shown an improved efficacy and safety profile compared to oral immunotherapy alone. However, immunotherapy-induced adverse reaction rates are high due to the risks associated with intentional allergen exposure. These results suggest that peanut immunotherapy has a promising role in the treatment of PA, although further studies are needed before its incorporation into standard of care.

Oral immunotherapy for peanut allergy: The con argument

Background

In some countries of the world, peanut allergy represents an important source of anaphylactic reactions. Traditionally treated with the avoidance of responsible allergens, this condition can also be targeted by oral peanut immunotherapy.

Methods

In this study, we review the beneficial and side effects of currently available forms of peanut oral immunotherapy (POIT). We report the discussions resulting from the publication of a meta-analysis that brought to light the downsides of oral immunotherapy for peanuts.

Results

In some clinical situations, the risk-benefit ratio can favor peanut oral immunotherapy over avoidance. In many other situations, this is not the case. The decision must be based on the values and preferences of clinicians and patients. Those not ready to accept serious adverse effects from POIT are likely to continue the elimination diet; those motivated to achieving desensitization, and prepared to accept serious adverse effects, may choose to undergo POIT.

Conclusions

Without being prejudiced against peanut oral immunotherapy, we indicate the possible evolution of treatment for this condition is in a rapidly evolving broader scenario. Among the future options, sublingual immunotherapy, parenteral immunotherapy with modified allergens, transcutaneous immunotherapy, and the use of biologics will become important options.

Pharmacotherapy in allergy medicine: from 'ipse dixit' to the evidence-based medicine

PURPOSE OF REVIEW

The aim of the article is to examine the contributions made in recent years by evidence-based medicine to the understanding, positioning, and use of drugs for the treatment of the main allergic conditions.

RECENT FINDINGS

Several antiasthmatic drugs have been reappraised for their efficacy characteristics and drug interactions in Cochrane reviews. The Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines have been reformulated in evidence-based medicine (EBM) terms in 2017; over these years, new point of care instruments contributed to the approximation of the guidelines to real life by drawing from the patients themselves information that allows to finely modeling the pharmacological suggestions. Last, at the time of the emergence of new drugs for the treatment of peanut allergy, new systematic reviews have helped to focus on the most suitable reference outcomes with the aim to respond promptly and adherently to patients' needs.

SUMMARY

EBM has contributed to changes in the GINA guidelines in the last two years. It has been instrumental in translating the ARIA guidelines in real life. It has also contributed to profiling the potential and limitations of oral peanut immunotherapy. In allergy medicine, EBM is a formidable aid for the advancement of knowledge.

Production of allergen-specific immunotherapeutic agents for the treatment of food allergy

Allergen-specific immunotherapy (IT) is emerging as a viable avenue for the treatment of food allergies. Clinical trials currently investigate raw or slightly processed foods as therapeutic agents, as trials using food-grade agents can be performed without the strict regulations to which conventional drugs are subjected. However, this limits the ability of standardization and may affect clinical trial outcomes and reproducibility. Herein, we provide an overview of methods used in the production of immunotherapeutic agents for the treatment of food allergies, including processed foods, allergen extracts, recombinant allergens, and synthetic peptides, as well as the physical and chemical processes for the reduction of protein allergenicity. Commercial interests currently favor producing standardized drug-grade allergen extracts for therapeutic use, and clinical trials are ongoing. In the near future, recombinant production could replace purification strategies since it allows the manufacturing of pure, native allergens or sequence-modified allergens with reduced allergenicity. A recurring issue within this field is the inadequate reporting of production procedures, quality control, product physicochemical characteristics, allergenicity, and immunological properties. This information is of vital importance in assessing therapeutic standardization and clinical safety profile, which are central parameters for the development of future therapeutic agents.