By Annelies Gartner

Accidental ingestion of peanuts can cause a life-threatening reaction for people who are allergic.

Using an investigational injectable medicine, the IgGenix ACCELERATE Peanut Study is helping to solve allergies and empower teens and adults to live without fear of anaphylaxis.

Dr Michael O’Sullivan, from UWA’s Medical School, is leading the Phase 1 trial at Fiona Stanley Hospital.

After completing an undergraduate degree in medicine at UWA, Dr O’Sullivan undertook specialty training in adult immunology and allergy, and then spent about 18 months at Princess Margaret Hospital for Children in paediatric allergy and immunology.

“I started to get involved in investigator-initiated research around paediatric food allergy,” he explains. 

“Then I extended on from that, recognising there was a lot of demand for food allergy treatment in adults and very little research was being done in that area.”

The technology behind the medicine used in the ACCELERATE study was developed by American biotech company IgGenix. 

“The research they led isolated individual immune cells that make allergy antibodies in someone with a peanut allergy,” Dr O’Sullivan says.

“They then re-engineered those antibodies to be essentially blocking antibodies — they block the immune system from being able to respond to the bits of the peanut that would otherwise trigger an allergic reaction.”

The company did not have the clinical capacity and expertise to undertake the Phase 1 trial so contacted Australia’s National Allergy Centre of Excellence (NACE), a collaborative group based out of  Murdoch Children's Research Institute.

Dr O’Sullivan and  Associate Professor Debbie Palmer, from UWA’s Medical School and The Kids Research Institute, are co-chairs of the NACE Food Allergy Stream, so his work as an adult immunologist in food allergy research was known to the centre.

“I was able to point them in the direction of some colleagues who I knew were interested in allergy research and were in allergy services at public hospitals,” he says.

“We've ended up with four sites in Australia for the study and that might grow with Phase 1B and Phase 2 studies.”

The study recruited patients 15 to 55 years of age who had a history of severe peanut allergy.

"If someone has a peanut allergy their immune system, their B cells, make antibodies that bind on to peanut,” Dr O’Sullivan explains. 

“When they eat peanut it binds on to those antibodies and switches on the immune cells that cause the release of things like histamine and tryptase and this causes the allergic reaction.”

As part of the trial, allergy suffers are given an injection of the peanut-blocking medication and then eat a small amount of the nut. 

The antibodies in the medication block the peanut before the immune system can recognise it.

Dr Michael O’Sullivan, UWA Medical School

 

“It doesn't get rid of the underlying allergy, but it essentially blocks the immune system from being able to react to peanut for as long as the medication is circulating around in the body.”

One of the benefits of the medication is its safe approach — unlike trials where the patient is fed a small amount of peanut to build up tolerance, this does not trigger an allergic reaction.

“It provides a safety net for people if they accidentally eat a small amount of peanut and should prevent them from having a reaction,” he explains.

“If they consume a large amount of peanut they should have less severe symptoms.”

Potentially patients would only need a dose once every month or every two or three months to be protected.

“You'd need ongoing treatment, but it would be maybe monthly or less frequent than that rather than daily,” he says. “If you stop, about six months later you'd be back to where you started.”

Currently people with severe allergies use an EpiPen, which contains adrenaline and is used as an antidote to a reaction that is causing symptoms such has coughing, wheezing, light headedness, rash, hives and stomach pain.

“Comparatively this medication is more like a vaccine that prevents the allergic reaction in the first place,” Dr O’Sullivan explains.

“Someone who gets an influenza vaccine makes antibodies to protect against an infection, an EpiPen is more like an antiviral someone takes once they get sick with influenza.”

Although some young children have the opportunity to retrain their immune systems to be less reactive to peanuts, eating a small amount to try to build up their tolerance is not always a viable option.

“For children who don't tolerate this approach because of the burden of that treatment, or when it doesn't work, it's good to have this option,” he says.

“It will also make allergies easier to manage when they start high school and become more independent and less closely supervised.”

Dr O’Sullivan says once researchers have “cracked the code” to treat peanut allergies the technique and technology should be transferable.

“It relies on getting the code for the antibodies and then being able to re-engineer the medication,” he says.

“The underlying technology that was used to sequence the individual cells took a long time to do for the first one or two patients, but they've now got thousands of patients who've been sequenced.

“The company has already got the code from people with allergies to cashews, egg, milk, wheat and shellfish.” 

The hope is that if this trial is safe and effective for someone with a peanut allergy then medications can be developed for not just other food allergies but also atopic diseases such as hay fever.

“It could work for hay fever and again, it would be a temporary thing, but someone who's got bad grass pollen allergy if you could find the relevant antibodies triggering the reactions, you could block them for the three or four months of the year that they're getting symptoms,” he explains.

A lot of the burden of peanut allergy for people is that risk of reactions and the relief this medication has the potential to deliver could be life-changing.

“Imagine if these people did not have to worry about cross-contamination or could travel to places with language barriers and not have to be concerned about anaphylaxis,” Dr O’Sullivan says.

Read the full issue of the Winter 2025 edition of Uniview [Accessible PDF].