Skin Patch for Peanut Allergy Showing Good Results
In 2014, researchers released results from a study on a new skin patch called Viaskin, aimed at treating peanut allergies. Now, more results have been released. The idea behind the patch was that by exposing people to small amounts of the protein in peanuts that causes allergic reactions, the patch could train the immune system to get used to the protein and recognize it as innocuous. The hope was that this approach – known as epicutaneous immunotherapy - would reduce or eliminate peanut allergy by desensitizing people to peanuts.
The creators of the patch suggest that the patch should be worn for three years, but the initial study was conducted over the course of just one year. This new set of results come from an extension of the original trial and involved patients using a higher dose patch for two years.
The new study showed that for children between the ages of 6 and 11, 83.3% were able to tolerate ten times the amount of peanut after wearing the higher dose patch than they could at the start of the study. These results suggest that the combination of higher dose and longer use is more effective, as only 53.6% of these children showed this improvement in the original study.
In the more recent study, 171 patients were studied. Of the 171, 97 were children. Unfortunately, the patch did not have the same beneficial impact on teenagers and adults as it did in children. Dr. Hugh Sampson, the Director of the Jaffe Food Allergy Institute at Mount Sinai in New York, therefore commented that the younger we can start those with peanut allergies on the patch, the better.
Why does the patch work better in children than in adults? The answer to this question may have to do with the specific cells that the patch works on – called Langerhans cells. These cells exist around hair follicles, and as you age the hair follicles spread apart, separating these cells. It therefore harder to get the same amount of the medicine to as many cells in older people than in younger people. It is therefore possible that a higher dose patch could be more effective in teenagers and adults than the patch that was used in the current study.
The company the produces the patch, Salmun, is hoping to apply for approval from the United States Food and Drug Administration (FDA) later this year. However, one critical question remains regarding the use of the patch: would users ever be able to take off the patch and continue to reap the rewards over the long-term? The company is currently conducting research to address this question, as well as ones to address safety issues. While the vast majority of study participants experienced no adverse side effects from the patch, 2.3% of the patients dropped out of the study due to symptoms.
The positive impact the patch has shown on children demonstrates the promise for skin patches in addressing food allergies. Another patch, for milk allergy, is currently in a Phase 2 trial, and there is pre-clinical work underway for an egg allergy patch.