Establishment of a new treatment for peanut allergy

Chief Investigator: Dr Billy Tao

Funding Amount: $73,155

Recipient: Flinders University

Overview:

Peanut allergy affects 3% of Australian children. It affects family lifestyle, is dangerous for those allergic, and constant vigilance is required. No treatment is available. We will, through a network of allergists, treat peanut allergy using an improved treatment protocol that uses sequential ingestion of 2 types of boiled peanuts followed by roasted peanuts to safely desensitise peanut-allergic children. This world-first home-based treatment will be supervised by allergists and will allow peanut allergic children to be safe from dangerous allergic reactions.

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Research Outcomes:

Researchers: Dr Billy Tao, Dr Tim Chataway, Prof Kevin Forsyth, Dr Luke Grzeskowiak

Research Completed: 2020

Research Findings: Majority of peanut allergic children in our study were safely and successfully desensitised outside hospital setting, using a novel treatment approach and involving only a small number of clinic visits and the use of boiled peanuts. Importantly, more than 80% of the children were able to tolerate peanuts at the end of the trial, while the intervention was well tolerated. This provides great promise in improving quality of life for those living with peanut allergies.

Key Outcomes:

Peanut allergy is the leading cause of food-related allergic reactions in children, while peanut oral Immunotherapy (POIT) is a well-researched method for desensitisation, based on the ingestion of gradually increasing amounts of peanut allergen under medical supervision and maintaining continued daily consumption afterwards. Its general acceptance by the medical community has been hampered by the high rate of adverse events (AEs) during treatment, mandating intensive medical supervision and multiple visits to hospitals or clinics for each up-dosing step, no less than 16-20 visits per course of desensitisation.

In two previous research projects, both funded by Channel 7 CRF, we have established that extended boiling could make peanuts hypoallergenic, and sequential POIT using extensively boiled and then roasted peanut was both safe and effective, allowing all up-dosing steps be performed at home in a proof-of-concept pilot study. Both studies were published in a peer-reviewed journal, and the current project is a Phase II clinical trial extension from the previous pilot study, with some changes such as the inclusion of more severe peanut allergy cases, starting with 12-hour boiled peanuts, and ingesting peanuts twice a day instead of three times a day.

1. 70 subjects were enrolled, and 56 (80%) reached the target dose of ingesting 12 roasted peanuts on a daily basis. This provides high level protection against accidental peanut ingestion in unexpected circumstances.
2. 14 subjects withdrew from the study at various stages, the main reasons were unwillingness or inability to adhere to written protocol, dislike of peanuts taste, change of family/social circumstances, and anxiety about treatment might adversely affect pre-existing conditions such as asthma or eczema. Only 2 participants (2.9%) withdrew because of AEs, which is significantly lower than the mean withdrawal rate of 6.6% due to AEs, cited in a recent meta-analysis paper¹ based on 27 published POIT clinical trials.
3. In line with the pilot study, all participants have had their up-dosing steps performed safely at home, with supervision from their parents, thus eliminating the need for multiple hospital or clinic visits, and there were a total of 52 up-dosing steps for each course of oral immunotherapy.
4. In a simple feed-back survey of participants, conducted immediately after the exit oral food challenge at the end of study, families had rated a mean of 9.7/10 for both overall satisfaction and safety, and a mean of 8.9/10 for ease to follow regarding the protocol (out of a scale of 0-10).
5. In terms of improvement in safety, we have observed significant reduction of AE frequency when compared with means figures from the meta-analysis data¹. For example, overall frequency was reduced from 81.3 episodes per 1,000 doses of peanut ingestion to 4.77 per 1,000 doses, while the frequency of AE requiring treatment was reduced from 11.35 per 1,000 doses to 2.44 per 1,000 doses, and use of adrenaline from 0.2 per 1,000 doses to 0.07 per 1,000 doses.

Conclusion: We have successfully demonstrated that a triple-phase peanut oral immunotherapy protocol beginning with hypoallergenic 12-hour boiled peanut, then 2-hour boiled peanut, and finally roasted peanut is easy, safe and effective, compared to conventional OIT methods using standard allergenic peanut proteins. Our method allows safe conduct of all up-dosing steps at home, thus eliminating the need for multiple visits to hospitals or clinics during desensitisation.

Research Papers: Reference:¹Grzeskowiak LE, Tao B, et al. Adverse events associated with peanut oral immunotherapy in children – a systematic review and meta-analysis. Scientific Reports, 10:659 | http://doi.org/10.1038/s41598-019-56961-3 (2020).

Related Publications:

Future Outcomes: