A vaccine that could enable people with celiac disease to safely consume gluten has begun phase 2 testing in the US, Australia, and New Zealand after more than a decade of development.
Results from several phase 1 trials previously showed that the immune system-modifying treatment, called Nexvax2, is safe and tolerable. The upcoming studies will evaluate its efficacy.
Nexvax2 reprograms T-cells so that they no longer attack certain amino acid sequences – peptides – within the proteins that constitute gluten by repeatedly exposing the body to modified forms of three of these peptides. (Gluten is not one molecule, but rather a composite compound made of several different energy and mineral-rich proteins that, alongside starch, are stored in grain seeds.) In about 80 to 90 percent of celiac cases, the patient’s inflammatory response to gluten – which leads to the destruction of the intestinal lining if gluten is consumed frequently – arises because they are carriers of the HLA-DQ2.5 gene. This gene creates a recognition protein that instructs T-cells to flag harmless gluten peptides as dangerous.
The vaccine will not work for individuals with non-HLA-DQ2.5-mediated gluten sensitivity.
“The initiation of our Nexvax2 Phase 2 trial is significant for patients who suffer from celiac disease, a condition affecting approximately 1% of the global population,” Leslie Williams, CEO of ImmusanT, the company behind Nexvax2, said in a statement earlier this year. “This trial is designed to demonstrate protection against inadvertent exposure to gluten, but the ultimate goal is to develop Nexvax2 as a treatment that will allow patients to return to an unrestricted diet.”