Acalabrutinib was recently approved to treat lymphomas by inhibiting an enzyme in cells that are known to be key to allergic reactions, including anaphylaxis.
After discovering that patients with food allergies had reduced skin test responses to those foods while taking the drug, researchers tested the drug’s ability to prevent reactions to peanuts in 10 adults with peanut allergy.
At baseline testing, patients reacted to a median dose of 29mg of peanut protein, about one-seventh of a peanut.
After receiving four doses of acalabrutinib over two days, seven patients tolerated the maximum 4,044mg of peanut protein without having an allergic reaction; the other three patients’ peanut tolerance increased between 32- and 217-fold compared to baseline testing.
While the study population was small, the results suggest acalabrutinib may have clinical use in preventing anaphylaxis in people with peanut allergies, said Bruce Bochner, MD, Professor Emeritus of Medicine in the Division of Allergy and Immunology and a co-author of the study.
Said Bochner:
Seven out of ten of these patients sailed through the peanut ingestion test without any reaction whatsoever after taking this drug. And for the three others, their threshold for reacting markedly improved,” Bochner said. “These subjects went from reacting to a fraction of a peanut to tolerating up to about 20 peanuts. Without any hyperbole, there is no drug ever tested that works this well to protect somebody from anaphylaxis.
Moving forward, Bochner said the findings need to be validated in larger trials. Because the drug can block allergic reactions to peanuts, it’s possible it could also block allergic reactions to other foods as well as other allergens like drugs, so such a pretreatment strategy could be useful if a patient needs to take a drug they are allergic to which has no other alternative, Bochner said.
Said Melanie Dispenza, MD, PhD, assistant professor of Medicine at the Johns Hopkins University School of Medicine and lead author of the study:
There are no known therapies that can reliably prevent anaphylaxis from allergens. BTK inhibitors like acalabrutinib are the first drugs shown to effectively prevent allergic reactions to foods with a rapid onset,” Dispenza said. “This finding is groundbreaking for the field of allergy and could dramatically change the way we treat food and drug allergies.