Combination peanut allergy treatment leads to fewer side effects
For around the past decade, a research group led by the Australia's Murdoch Children’s Research Institute (MCRI) has been investigating treatments for peanut allergies in children, and study by study, they are making some exciting progress. The latest results have reaffirmed the team's promising earlier findings, and also teased out new insights around long-term treatment outcomes and how side effects might be kept to a minimum.
With around three percent of babies born with an allergy to peanuts, the condition poses a serious problem for parents trying to avoid adverse reactions, especially as they start to walk and shove random things in their mouths, mingle at birthday parties and hit the schoolyard. Through a series of multi-year studies, the MCRI team has been exploring potential treatments that combine probiotics with what's known as oral immunotherapy.
The probiotic in question is a bacteria called Lactobacillus rhamnosus, which can be found in yoghurt and dairy products, while the oral immunotherapy involves giving allergic children small doses of peanut protein each day, gradually increasing it to a daily dose of two grams (0.7 oz) to build up their tolerance.
This proved highly effective in a trial involving more than 60 children, with results published back in 2015 showing that 82 percent of the treated children were able to safely eat peanuts a few weeks after conclusion of the therapy. The real question was whether these results were long-lasting, and a follow-up study published in 2017 provided some compelling answers. That study checked in with the original participants after four years to see if this newfound tolerance to peanuts had been maintained. The authors found that 80 percent of the subjects that had developed peanut tolerance were still able to regularly eat peanuts with no trouble.
For their latest study, the scientists enlisted 201 children aged between one and 10, and set out to explore whether combining the probiotic with the oral immunotherapy conferred any benefits when compared to the immunotherapy on its own.
After 18 months of treatment, the scientists found 46 percent of those receiving the combination treatment were in clinical remission, as were 51 percent of children receiving the oral immunotherapy alone and five percent of the placebo group. In fact, around three quarters of the oral immunotherapy group were able to tolerate standard serves of peanuts, but 99 percent of those in remission were able to simply consume them as they wished 12 months after finishing the treatment.
“The results show that high dose peanut oral immunotherapy provides meaningful benefit to treated children,” said team leader Professor Mimi Tang. "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 desensitized to this amount of peanut.”
When it came to combining the oral immunotherapy with the probiotic, the team found it didn't have a huge effect on overall effectiveness but did seem to lead to fewer complications, particularly in younger subjects.
“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," said Tang.
The authors note that attaining clinical remission is a more favorable outcome than desensitization, which still involves ongoing treatment and allergen avoidance, impacting on quality of life. They also say that the results indicate intervention at a young age appears to be the best route to achieving this aim.
“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," said Tang. "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.”
The research was published in the journal The Lancet Child & Adolescent Health.