Phase 2 trials about to start with a therapeutic vaccine, Nexvax2, that has the potential  to protect coeliac patients from the adverse events caused by gluten exposure.

Multicentre trials, including centres in Australia, are planned to start in mid 2018 to investigate whether regular use of the vaccine can desentisise patients with coeliac disease to three dominant gluten peptides.

The drug Nexvax 2 has been in the pipeline for almost two decades and is now finalising phase 1b trials, according to Dr Bob Anderson, an Australian gastroenterologist who discovered the three peptides used in Nexvax2 while working at the Walter and Eliza Hall Institute, Victoria.

Dr Anderson

Dr Anderson, who is now Chief Scientific Officer for vaccine developer Immusan T in the US, told the limbic that if the trials are a success, the treatment would offer people with celiac disease the first medication to protect against gluten exposure.

However, patients would still need to remain on gluten-free diet.

“People on the [gluten free] diet often have gluten exposure inadvertently and they get acute symptoms two to four hours later. When we have done surveys (of patients) what they want first is protection from that type of exposure, from being so- called ‘glutenated’,” he said.

“Ultimately though the vision is that it could provide tolerance to gluten and allow an unrestricted diet.”

Dr Anderson said the term “vaccine” may confuse some people, when in reality it was being trialled in doses given twice a week.

“It’s got some similarities to allergy sensitisation, you’re targeting one part of the immune system and aiming to modify that by delivering the antigen which (the immune system is) reacting against in a very controlled way.”

But a desensitising “vaccine” approach could represent  new class of drug for treating other autoimmune diseases such as rheumatoid arthritis and Type 1 diabetes, according to Dr Anderson.

“In theory, (these diseases) are all because of immune reactions that have developed in people and started to cause tissue damage. And if you knew what exactly what the immune reaction was targeting then this kind of approach would probably be successful and our interest is to see if we could advance the discovery side.”

The three selected peptides in the vaccine elicit an immune response in patients with coeliac disease who carry the immune recognition gene HLA-DQ2.