Meet our brilliant minds: Professor Mimi Tang
Allergies
A peanut allergy—the most common cause of life-threatening anaphylaxis—is more likely to result in death than any other reaction to food. And it has been steadily on the rise. In the last 20 years, peanut allergies have increased more than 350 per cent.
Mimi’s study combined a probiotic and peanut protein—the first time ever a probiotic had been coupled with oral immunotherapy—with astonishing results.
Eighty-two percent of children with peanut allergy who underwent the therapy in her Melbourne-based trial were able to tolerate peanut, compared to four per cent in the placebo group.
It was more than researchers could have hoped for. These kids could now go to parties, school camps and travel overseas without fear of death from accidentally consuming peanuts. It was a relief for children and it was a weight lifted off the shoulders of their stressed parents.
“If you treated nine children, seven would benefit,” Mimi explains of the study, the Probiotic and Peanut Oral Immunotherapy for treatment of peanut allergy trial (PPOIT). “When we started, we thought the probiotic would improve the ability for oral immunotherapy to induce tolerance. But we had not expected that improvement would be of such a huge magnitude. We were very excited.”
So, it seems, is everyone else—researchers and allergy sufferers alike. As interest and momentum built following the study, Mimi decided to step aside as head of Allergy and Immunology at RCH to focus on the research.
Emails flood into her inbox daily from people outside Melbourne wanting their children to be involved in further trials. Some interstate parents have even considered moving their families to Victoria. But they may not have to make such a drastic move – the next study in 2016 will be a $2.8 million multi-centre trial across Perth, Adelaide and Melbourne involving 200 children.
Mimi hopes the new trial will answer two questions. Firstly, to prove adding the probiotic does give a benefit over and above oral immunotherapy alone, and secondly, to see if the combination therapy can give allergy sufferers longer-lasting tolerance.
Most other studies using oral immunotherapy alone to induce tolerance, Mimi says, have limited success. Only about 17 per cent to 30 per cent of those treated gained tolerance.
So why did she think a probiotic might hold the key?
The seeds of this idea were sown over a decade ago. Mimi has long been intrigued by probiotics and healthy gut bacteria, and studies emerged showing probiotics taken in the last weeks of pregnancy and the first few months of a child’s life could prevent the development of eczema in babies.
This original study used bacteria called lactobacillus rhamnosus—the probiotics used in Mimi’s PPOIT study—which seemed to promote tolerance responses in the gut.
“I had an idea. Literally, it was just an idea,” says Mimi.
“I thought if we presented a probiotic, together with the allergen, that probiotic may be able to provide the right environment to encourage the immune system in a different direction to its current default. That’s why I did it.”
The internationally-renowned allergist is not content to stop at peanut allergy. In the future, she wants to see if the combined therapy works for other foods and if it works for adults and to refine the therapy.
But for now, she is full of gratitude, pride and satisfaction the 10-year journey has culminated in what all medical researchers ultimately want.
“It is just a wonderful feeling that we have made a difference, finally. That’s what medical research is all about. We all want to make a difference.”