2. Oral Immunotherapy
In the last few years, there’s been an increase in studies evaluating oral immunotherapy for peanut allergies.
In 2018, a double-blind, placebo-controlled food challenge published in The New England Journal of Medicine found that oral immunotherapy in children and adolescents who are highly allergic to peanuts may lower symptom severity during peanut exposure.
This was the third phase of ongoing trials testing the efficacy of oral immunotherapy, which is when patients receive a peanut-derived immunotherapy drug in an escalating dose program.
Here are some highlights from the study:
- 551 participants with peanut allergies, the majority of whom were between the ages of 4 and 17, received a peanut-derived drug called AR101 or placebo in escalating doses for 24 weeks.
- By the end of the trial, 67 percent of participants in the treatment group and 4 percent in the placebo group were able to ingest a dose of 600 milligrams or more of peanut protein without displaying dose-limiting symptoms.
- Those using oral immunotherapy also experienced lower symptom severity during peanut exposure compared to those taking the placebo.
- During what was called the “exit food challenge,” when individuals ingested a dose of 600 milligrams or more of peanut protein at the end of the trial, the maximum severity of symptoms was moderate in 25 percent of the participants in the treatment group and 59 percent of those in the placebo group.
A three-year study very recently published in September of 2019 evaluated the sustained effects of peanut allergy oral immunotherapy.
Here are the highlights of this most recent study:
- 120 participants with a peanut allergy aged 7–55 years were randomly assigned into one of three groups.
- One group involved taking 4,000 milligrams of peanut protein for 104 weeks and then discontinuing use, the next group received 4,000 milligrams of peanut protein for 104 weeks and then ingested 300 milligrams daily for another 52 weeks, and the placebo group received oat flour.
- Researchers found that peanut oral immunotherapy was able to desensitize individuals with peanut allergy and discontinuation or even reduction in daily peanut intake could increase the likelihood of regaining allergy symptoms.
- Over the entire study, the most common adverse events were mild gastrointestinal symptoms, which were seen in 90 of 120 patients, and skin disorders, which were seen in 50 of 120 patients. These adverse reactions decreased over time in all groups.
- Two of the patients in the peanut group had serious adverse events during the 3-year study period.
Studies like these have been so successful that the FDA advisory just recommended a peanut allergy treatment for approval.
The drug, which is called Palforzia, is a type of oral immunotherapy that’s meant to expose patients with peanut allergies to increasing doses of peanut protein in order to build a tolerance over time.
As scientists research the critical role of intestinal microbiota in the development of immune tolerance, there is more and more interest in the benefits of probiotics.
Probiotics are able to re-colonize and restore microflora in the intestinal tract.
Several studies have been recently conducted on the role of probiotics in preventing and treating allergic disorders. Some impressive findings include the following studies:
- A 2005 study conducted at Ninewells Hospital and Medical School in the U.K. indicates that the management of allergies has been shown with probiotics reducing the incidence of atopic eczema. Probiotic treatment was demonstrated in infants using lactobacillus.
- Recent studies have shown that when probiotics are combined with minuscule amounts of peanut protein, it serves as a natural form of oral immunization and can help to alleviate peanut allergies and sensitivities.
- A 2015 study published in the Journal of Allergy and Clinical Immunology evaluated 62 children between the ages of 1–10 years who received combined therapy involving probiotic supplementation and peanut oral immunotherapy. Of the children in the treatment group, 89.7 percent were desensitized to peanuts and 82 percent achieved unresponsiveness, which means that they had reduced peanut skin prick test responses and peanut-specific IgE levels. Researchers concluded that the combination of probiotics and very small amounts of peanut protein induced immune changes that modulated the child’s peanut-specific immune response, making them more tolerant to peanuts.
- In 2017, a follow-up study published in The Lancet Child and Adolescent Health was conducted to assess the long-term outcomes of the children who originally underwent probiotic and peanut oral immunotherapy treatment 2–4 years prior. Sixty-seven percent of the children in the original treatment group were still eating peanuts. Four of the 24 children in the treatment group reported allergic reactions to peanuts since stopping treatment, but none had anaphylaxis. Researchers of this follow-up study concluded that this form of treatment provides “long-lasting clinical benefit and persistent suppression of the allergic immune response to peanuts.”