FCAAIA Notes: The “peanut patch” is not FDA approved and is not commercially available. Let’s assume it is someday. Then, what might we expect from it? Use of the patch will not “cure” peanut allergy, nor will it be a free license to eat peanut products. Users will still need to avoid peanut in their diets at least as things stand now. At this point it seems that the patch merely increases the amount of peanut that must be ingested before there is a clinical reaction and the increase in the amount tolerated will vary from patient to patient. There also no data as to what happens if someone stops using the patch. Might the level of tolerance decrease after stopping it?
Oral peanut desensitization is also under clinical investigation. Patients who undergo successful oral desensitization appear to tolerate more peanut with ingestion than those who use the patch, but also do not appear to be “cured” with any great frequency. Oral desensitization is not risk-free and most patients have some clinical reaction during the procedure.
(Source: http://www.medscape.com/viewarticle/877037?src=WNL_confwrap_170320_MSCPEDIT&uac=112079PK March 20, 2017. For Medscape articles: User name: FCAAIA, Password: Allergies)
Children became progressively less sensitive to peanuts during a 3-year trial of immunotherapy delivered through a skin patch. There were few adverse effects from the patch, and the children were comfortable with wearing it.
“This is something we believe will provide protection,” said study investigator Hugh Sampson, MD, from Mount Sinai Medical Center in New York City, who is chief scientific officer of DBV, the maker of the Viaskin skin patch.
Dr. Sampson presented results for children 6 to 11 years of age from the phase 2b OLFUS open-label extension phase of the VIPES study during a news conference at the American Academy of Allergy, Asthma and Immunology Meeting.
Peanut allergies are becoming increasingly common. Both oral and sublingual immunotherapies, in which small amounts of peanut are gradually introduced, have shown promising results. However, children are sometimes afraid to eat even these small doses, and adverse effects are common. In fact, the US Food and Drug Administration has not approved any immunotherapy for peanut allergy.
The skin patch, the size of a round Band-Aid, acts as a condensation chamber, applying small amounts of peanut to the skin. Every day a new patch is adhered to a different area of the body.
Natural water loss from the skin dissolves and releases the peanut protein, which penetrates the stratum corneum. It is believed that Langerhans cells then transport the peanut protein to lymph nodes, where regulatory T-cells are activated.
In the VIPES study (NCT01675882), Dr. Sampson and his colleagues assessed 221 people 6 to 55 years of age with a peanut-specific immunoglobulin (Ig)E level above 0.7 kUA/L, a wheal diameter on a skin-prick test of at least 8 mm, and an allergic reaction to 300 mg of peanut protein or less. Participants received peanut doses of 50 µg, 100 µg, or 250 µg, or placebo for 12 months. Responders were defined as people who could eat at least 1000 mg of peanut protein without a reaction, or people who had at least a tenfold increase over baseline in the eliciting dose of peanut protein.
Results were best with the 250 μg dose, so all study participants, including those in the placebo group, were invited to join the OLFUS extension (NCT01955109) and continue on that dose for another 24 months; 171 adults and children enrolled.
At the end of the extension period, after 36 months of treatment with the skin patch, 15 of the 18 children (83.3%) met the definition of responder.
“I think that’s pretty good,” said Dr. Sampson.
This was an increase over the 53.3% rate of responders at 12 months. And the median cumulative reactive dose increased from 444 mg at 12 months to 1440 mg at 36 months.