Researchers are studying a possible vaccine and ways to desensitize the body to several food allergies at once.
Allergy treatments haven’t seen much progress in decades, but universities, investors, and corporations are pouring money into research on the root causes, hoping to create new, more effective therapies. “I foresee that a lot of allergy therapies will become more and more specific and targeted, and more customizable to the individual patient,” said Andrew Long, the lead investigational drug pharmacist at a Stanford center for allergy research named for major donor Sean Parker, a co-founder of Napster.
Hundreds of millions around the world suffer. As many as 10 percent of American children have hay fever. Some 5 percent or more of the nation’s children and 4 percent of adults may have food allergies, though the standard tests aren’t completely reliable, according to a 2016 study from The Asthma and Allergy Foundation of America.
A coalition of researchers from the Massachusetts Institute of Technology, Harvard, and Yale focused on genetic research launched an initiative in June 2016 to accelerate allergy research. Interactions between “genes, gut microbes, the immune system, and food” have led to a “breakdown in tolerance,” the group wrote. The group plans to use single-cell genomic analysis, looking at individual cells involved in an allergy reaction, and CRISPR genome-editing techniques, which will enable it to screen out individual genes and see the role each plays in food allergy.
Interestingly, some people show evidence of an allergic response in the lab but don’t have symptoms — and other people have symptoms but don’t test as allergic.
Peanuts. Nestlé has been investing in the startup Aimmune, which has identified the proteins in peanuts that trigger reactions and put them as a powder in capsules. Patients might start by taking half a milligram of the proteins and work up over six months to consuming the amount of protein in one peanut. Allergists have been making their own peanut protein concoctions to desensitize patients.
Multiple food allergies. About 70 percent of people who have an allergy to one kind of food will also be allergic to another, Long says. In standard desensitization strategies with allergy shots, it could take years to successfully cut the reaction to just one food. The Stanford researchers are testing omalizumab (Xolair), an asthma drug, on patients with food allergies, as a way of speeding up the process and applying it to five foods at a time.
An allergic response begins when contact with the allergen triggers immunoglobulin E, or IgE, which then signals two kinds of immune cells — mast cells and basophils — to release a flurry of chemicals that are designed to “fight” the allergen. Omalizumab interferes with the second step, binding to human IgE and blocking it from triggering the other cells.
But why not stop the triggering of IgE? A Harvard team led by statistical geneticist Liming Liang has found 30 genes involved in the allergic response. The goal is to identify a target that can be altered by medication.
A Canadian research team has shown that it can cut the potentially deadly anaphylactic response to peanut and egg proteins in mice by up to 90 percent, by triggering a natural “off” switch in the immune system. In 2010, the same group demonstrated that it could reverse an asthmatic response in human cells in a test tube. The ultimate goal would be a desensitizing shot that could work on food allergies, asthma, or even multiple sclerosis, which also involves the immune response. The first human trial could begin in the fall of 2017.
A vaccine. Hay fever is a huge global market. About a quarter of the Japanese suffer from it, for instance. Astellas Pharma is developing a vaccine using a fragment of the DNA in the allergen. Ideally, the vaccine could trigger resistance without ever exposing the patient to the entire antigen — which could cause a reaction. The goal is a kind of vaccine template that would allow researchers to swap in DNA fragments from different allergens, say cat dander or peanut protein.
None of these approaches is a sure bet. Circassia Pharmaceuticals has had an eagerly-awaited drug for cat allergies in the pipeline, which failed to beat placebo in its latest trial.
“In school, we didn’t learn anything about allergy treatment, except antihistamines and epinephrine,” Long said. “But now, we’re seeing this whole new spectrum of treatments. It’ll be interesting to see how this translates into making it into a pharmacy, and into the hands of patients.”
March 31, 2020
Janet O’Dell, RN