The goal of this study is to test the safety and feasibility of a change in management approach for infants with newly diagnosed egg allergy. Infants with newly diagnosed egg allergy will have egg introduced via a gradual and graded home based approach known as an "egg ladder" supervised by a dietitian. The main questions this study aims to answer are how safe and feasible are home-based dietitian-led "egg ladders" as a treatment pathway to achieve tolerance of egg for newly diagnosed infants with egg allergy.

This prospective trial will evaluate the safety and feasibility of a change in practice for infants with newly diagnosed IgE-mediated egg allergy managed by the Department of Allergy and Immunology at the Royal Children's Hospital (RCH). Children <12 months of age with clinician diagnosed IgE-mediated egg allergy, who do not have a history of severe anaphylaxis to egg will be offered cautious, home-based egg introduction via a standardised 'egg ladder' protocol with dietitian support. An egg ladder is a form of dietary advancement therapy that aims to facilitate the development of natural tolerance through the gradual introduction of egg with increasing allergenicity and quantity. Although increasingly becoming widespread in clinical practice, this is yet to be evaluated in Australia via a prospective study. The HealthNuts cohort study has shown that 80% of 12-month-old infants tolerate baked egg (eg in a muffin) and 47% have naturally outgrown their egg allergy (tolerating raw egg) by 2 years of age which was 1 year from their egg allergy diagnosis.

Current practice at RCH allergy clinic for infants with egg allergy is to recommend they avoid all forms of egg until 2 years when an inpatient baked egg challenge in the form of a muffin may be offered. If passed, the children can include baked egg products at home but must avoid cooked and raw egg until a resolution challenge is offered 12 months later (cooked egg in the form of well-cooked scrambled egg). Raw egg hospital challenges are no longer offered at RCH. Review of the inpatient challenges at RCH undertaken from January - June 2023 found the median age for a baked egg challenge was 5 years and a cooked egg challenge was 4 years with a current waitlist of 1200 patients. This current model of care is prolonging the burden of food allergy management for these families for years beyond the time where resolution has likely to have occurred in the overwhelming majority. Furthermore, children are reviewed by the Allergy physician yearly if diagnosed <12 months of age and then every 2 years after that, which adds further pressure to outpatient waitlists for allergy clinics.

We will establish the safety of our 'egg ladder' protocol by collecting adverse events (AE) from baseline (egg allergy diagnosis) to final follow up (12 months after egg allergy diagnosis). The feasibility will be determined by the proportion of children who complete all stages of the egg ladder at 12 months from their diagnosis (egg allergy resolution). Barriers to completing the egg ladder protocol, parent reported quality of life and anxiety will be captured from baseline to final follow up 12 months after egg allergy diagnosis.

Inclusion Criteria:

• infants aged greater than 4 months and less than 12 months of age diagnosed by an RCH allergist with IgE- mediated egg allergy in conjunction with a positive skin prick test (SPT) or specific immunoglobulin E (sIgE) to egg white
• has a legally acceptable representative capable of understanding the informed consent document and providing consent on the participants behalf

Exclusion Criteria:

• any history of severe food induced anaphylaxis. Defined as reaction requiring 2 doses of intermuscular adrenalin
• Physician diagnosed recurrent wheeze
• Not commenced or unable to eat solid food
• prescribed beta-blocker medication

The de-identified data set collected for this analysis of the Egg Up trial will be available six months after publication of the primary outcome. The study protocol may be obtained from the Murdoch Children's Research Institute. Prior to releasing any data the following are required: a data access agreement must be signed between relevant parties, the Egg Up trial investigators must see and approve the analysis plan describing how the data will be analyzed, there must be an agreement around appropriate acknowledgment and any additional costs involved must be covered. Should the study investigators be unavailable, this role is delegated to the Murdoch Children's Research Institute. Data will only be shared with a recognized research institute which has approved the proposed analysis plan.

6 months after publication of the primary outcome

Prior to releasing any data the following are required: a data access agreement must be signed between relevant parties, the Egg Up trial investigators must see and approve the analysis plan describing how the data will be analyzed, there must be an agreement around appropriate acknowledgment and any additional costs involved must be covered.