The Viaskin Peanut Patch: Will It Help Prevent Anaphylaxis?
Local allergist Dr. Shahzad Mustafa has been closely monitoring clinical trials for a new peanut patch that would help decrease the risk of an allergic reaction after accidental ingestion. Worn on the back or the inside of the upper arm, there were very few side effects in a recent study except for mild skin irritations. After 1-2 years of using the patch, close to 50% of the 74 participants saw a 50% improvement in peanut tolerance. DBV Technologies hopes to have the product approved by the Food and Drug Administration and marketed by 2018.
The Viaskin Peanut Patch: Will It Help Prevent Anaphylaxis?
By Janet Goldman
February 11th, 2017
DBV Technologies has been developing the Viaskin Peanut Patch, a new method for preventing anaphylaxis. If used appropriately, the patch can increase tolerance to peanuts. The patch helps peanut allergic individuals who accidentally ingest or are accidentally exposed to peanut protein. Through immunotherapy, the patch can help prevent symptoms from an accidental exposure. However, even with a patch, users should still always carry epinephrine and strictly avoid peanuts.
According to the American Academy of Allergy Asthma and Immunology (AAAAI), a study of 38,480 children (up to 18 years old) found 8% to have food allergies, with peanuts being the most common allergen. Furthermore, AAAAI reported “38.7% of food allergic children have a history of severe reactions.”1 Avoidance of food allergens Presents challenges on a daily basis, and can also be related to significant anxiety.
The patch delivers the allergen through the skin and directly to the lymph nodes, altering the immune system. Unlike oral drugs and other forms of immunotherapy, the patch doesn’t affect the blood stream. Consequently, users have had minimal side effects, primarily different forms of skin reactions, such as itching or rashes. Regarding the patch’s purpose, Dr. Shahzad Mustafa, an allergist in the Rochester area, said “the goal of the patch is to decrease the risk of allergic reaction in the setting of an accidental ingestion. Ideally the patch may also facilitate the resolution of peanut allergy, but this is not the primary goal.”
DBV’s clinical trials for peanut allergies began back in 2010. Encouraging results were recently published from an ongoing trial sponsored by the National Institute of Allergy and Infectious Diseases (NIAID). With 74 participants, aged 4 to 25, close to 50% had successful results. Most effective were the results for those of the age group 4 to 11. “It’s hard to know why the results were more promising for this age group as compared to older individuals,” said Dr. Mustafa, “but it may be due to plasticity of the immune system.” The participants received preliminary tests to determine their tolerance levels for peanut protein. Then they were separated into three groups: recipients of skin patches containing 250 micrograms of raw peanut extract; recipients of skin patches containing 100 micrograms of raw peanut extract and a placebo group whose patches didn’t contain any peanut extract.
All participants changed their patches daily. As small as a quarter, the patch is adhesive. Children wore their patches between their shoulder blades of their back. The older participants, adolescents and above, wore their patches on the inside of their upper arm. Regarding the onset of efficacy, Dr. Mustafa explained it “should happen relatively quickly, but I do not know the exact time course. I would guess within days to weeks. The studies showed continued improvement in effectiveness between 1 and 2 years of therapy.”
Dr. Mustafa emphasizes that “there is minimal to no risk for systemic reactions or anaphylaxis. “Most individuals will experience local dermatitis, similar to eczema. The severity of this reaction will vary for individuals. Regarding the significance of daily changing the patch, Mustafa explained “If doses are missed or patches are not changed daily, effectiveness can no longer be predicted.”
After one year of the NIAID study, the patients were again tested for peanut tolerance. To be categorized successful, the participant’s tolerance needed to improve tenfold or to a goal dose of 1000 mg of peanut protein, which represents roughly 3 peanut kernels. Those of the non-placebo groups tested with close to 50% success. Its’ noteworthy to comprehend the significance of the tenfold increase; the tolerated quantity was still very small. It has been reported that on average, participants on the low dose patch could eat 1/7 more of a peanut and those on the higher dose patch could eat an additional half of a peanut.
The patch’s easy application, with minimal risk, has been attractive to many. One participant’s mother enrolled her nine-year old son for safety reasons; she wanted to help him avoid reacting to peanuts. The required treatment period is not clearly defined; it could be one year, three years, or some other number. Similarly, the desensitization period is not yet known. It will take time to determine how well patients can maintain their immunity upon completion of the patch treatment.
Mustafa plans to prescribe the Viaskin Peanut Patch when it becomes available, but does not think it will be appropriate for all of his peanut allergic patients. He said that individuals with multiple food allergies and other typical allergic conditions such as eczema and asthma could also be considered for therapy with the patch” When asked whether he expects his patients to have a 50% success rate, he answered “I think it is impossible to put a number on what percentage of individuals respond to the patch, but I would say that all individuals will NOT experience a clinically significant increase in threshold dose of peanut. And it is impossible to tell the responders from the non-responders.”
Clinical trials continue for the most recent study’s participants; total test time being 2 ½ years. It is hoped to have the product approved by the Food and Drug Administration and marketed by 2018. Meanwhile, DBV is also developing similar plans for extending the trials to older age groups, other allergy groups such as eggs and milk and other medical fields such as Crohn’s disease.
Jon Terry, founder of The Allergy Advocacy Association says he is looking forward to Viaskin joining the ranks of prescription allergy medications. “Perhaps it will help prevent anaphylaxis caused by accidental exposure or ingestion of peanut protein to notably vulnerable patients, particularly young children between the ages of 4 and eleven years old,” he said. “Society in general and the medical profession specifically will have to wait until the medication comes into daily usage by patients before coming to any definitive conclusions. We are all on the verge of entering a whole new world.”
© Copyright Allergy Advocacy Association 2017.