Hope for peanut allergy sufferers

Researchers have discovered two peanut allergy treatments for children that are both highly effective at inducing remission.

The research, led by the Murdoch Children’s Research Institute (MCRI), found the treatments – a combination of a probiotic together with oral immunotherapy (the gradual introduction of the allergenic food) and oral immunotherapy alone – significantly induced remission and desensitisation. About half of the children achieved remission, allowing them to stop treatment and safely eat peanuts freely. Both treatments also provided substantial improvement in quality of life compared with current standard care.

The randomised controlled trial conducted at The Royal Children’s Hospital in Melbourne, Perth Children’s Hospital, and the Women’s and Children’s Hospital in Adelaide involved 201 children aged between 1-10 years. The trial was staged over four years, with participants followed up to 12-months post-treatment.

The team led by MCRI Professor Mimi Tang had previously shown that the combination treatment resulted in 74 per cent achieving remission after 18 months of treatment, and 70 per cent of those initial responders remained in remission and were eating peanuts safely four years later. The next step was to test whether adding a probiotic gave a benefit over and above oral immunotherapy on its own and to compare long-term outcomes following treatment.

The new research, published in The Lancet Child & Adolescent Health, found after 18 months of treatment, 46 per cent and 51 per cent of children who received the combination treatment or the oral immunotherapy alone, respectively, were in clinical remission compared to 5 per cent in the placebo group. The children who reached clinical remission were able to stop treatment and eat around a standard serving of peanut freely. Both treatments also led to a significant improvement in quality of life, with those children who achieved clinical remission experiencing the biggest improvement, greater than those who only achieved desensitisation.

“The results show that high dose peanut oral immunotherapy provides meaningful benefit to treated children,” Professor Tang said. After 18 months of treatment, 74 per cent of children who received the oral immunotherapy tolerated roughly a standard serve of peanut, equal to a snack pack of peanut M&Ms, 51 per cent achieved clinical remission and were able to stop treatment altogether, while the remaining 24 per cent were desensitised to this amount of peanut.”

“Addition of a probiotic did not significantly improve effectiveness compared to oral immunotherapy, however, it appeared to enhance tolerability of the treatment, with fewer gastrointestinal symptoms, especially in children between one and five years of age.”

The results also showed that treatment with oral immunotherapy, with or without a probiotic for childhood peanut allergy, provides a significant and substantial improvement in quality of life compared with current standard care, which is peanut avoidance.

MCRI Dr Paxton Loke said remarkably 99 per cent of children who achieved remission and ceased treatment were eating peanuts as frequently as they liked in the 12 months after stopping treatment.

“Children who were in clinical remission had fewer reactions to peanut compared with those who were just desensitised,” he said.

“Being desensitised still requires continued daily treatment and allergen avoidance so remission appears to be a better outcome for children. Importantly, children in remission had a significantly improved quality of life compared with allergic children, suggesting that no longer having to avoid peanut provides greater benefit than continued allergen avoidance despite the risk of a possible reaction.”

The peanut oral immunotherapy approach used in the trial applies a proprietary high dose, rapid escalation regimen that is being developed by Prota Therapeutics as a lead candidate for the treatment of peanut allergy, PRT120. Prota Therapeutics is an Australian biotech company, focused on bringing its allergy immunotherapy treatment for children with life-threatening peanut allergies to market.

Kate Lawlor’s son Declan, 9, who took part in the trial, is now in clinical remission and eats peanuts weekly. Declan was diagnosed with a peanut allergy at age four after having a reaction to peanut butter.

Kate said it was a huge relief that her son could now eat peanuts freely without fear of a reaction or having to avoid the nut for the rest of his life.

“Having a child with a food allergy is quite stressful,” she said. In the home, you can control the environment around food but school, play dates and birthday parties are largely out of your hands.”

“With Declan now in remission a lot of anxiety has been lifted and he is enjoying eating peanut chocolate M&Ms. He sees this as a real treat and looks forward to eating them every week.”

Peanut allergies are the most common cause of severe allergic reactions, called anaphylaxis, and one of the most frequent causes of death from food allergy. About 3 per cent of babies have a peanut allergy.

“As there is currently no cure, patients must adhere to strict allergen avoidance, which leads to psychological distress and reduced quality of life,” Professor Tang said.

“There is a need for disease-modifying therapies that improve health and well-being and both the combination and standalone immunotherapy treatments provided a meaningful benefit. The combination therapy, in particular, could offer a safe and well-tolerated approach to inducing clinical remission in young pre-school children with peanut allergies. Starting treatment early seems to increase the chances of achieving remission and pre-school children are especially vulnerable, so a treatment that causes fewer side effects brings an important advantage.”

Researchers from The Royal Children’s Hospital, Monash Children’s Hospital, University of Melbourne, University of Adelaide, Women’s and Children’s Hospital in Adelaide, Perth Children’s Hospital, The University of Western Australia, Telethon Kids Institute, Monash University and University College Cork in Ireland also contributed to the study.

Publication: Paxton Loke, Francesca Orsini, Adriana C Lozinsky, Michael Gold, Michael D O’Sullivan, Patrick Quinn, Melanie Lloyd, Sarah E Ashley, Sigrid Pitkin, Christine Axelrad, Jessica R Metcalfe, Ee Lyn Su, Dean Tey, Marnie N Robinson, Katrina J Allen, Susan L Prescott, Audrey Dunn Galvin, Mimi LK Tang and the PPOIT-003 study group. ‘Probiotic peanut oral immunotherapy versus oral immunotherapy and placebo in children with peanut allergy in Australia (PPOIT-003): a multicentre, randomised, phase 2b trial,’ The Lancet Child & Adolescent Health.

*The content of this communication is the sole responsibility of MCRI and does not reflect the views of the NHMRC.