番茄社区

SAN DIEGO -- A skin patch offered peanut-allergy immunotherapy without risk of systemic reactions but also with questionable efficacy, a pilot trial showed.

The only anaphylaxis event outside of oral food challenges seen among 54 severely allergic children treated with the quarter-sized patch for 18 months occurred after an apparently high dose of peanut consumed in a kebab outside the study.

The only other serious adverse events possibly related to the patch were hospitalization for skin abscess in a child with a skin disease and a case of herpetic mouth sores, Christophe Dupont, MD, PhD, of Necker Enfants Malades Hospital in Paris, reported here at the American Academy of Allergy, Asthma, and Imunology meeting.

"With this technique, you can deal with very severe allergy without any risk," he told 番茄社区. "Any reaction, just take the patch off."

Local skin reactions were common, at 62% overall and 30% with moderate severity.

However, the trial missed its primary efficacy endpoint, showing no difference over placebo in the 6-month rate of treatment response.

Only 12.5% on the Viaskin patch -- compared with 10.5% on placebo -- reached at least 1,000 mg peanut protein without reaction on double-blind food challenge, or increased their reactive dose at least 10-fold at that point (P=0.107).

An additional 12 months of open-label treatment in the boosted the responder rate to 10 to 15 who reached that point to date (67%), but only four got there by ingesting 1,000 mg of peanut protein. Reaching the other endpoint -- increasing the reactive dose 10-fold -- could mean just going from 1 mg to 10 mg, which wouldn't come near the 250 mg of protein found in one peanut, noted , of Mount Sinai Hospital in New York City.

He pointed to the low peanut dose used in the study -- just 100 mcg -- and the relatively low threshold used for efficacy as potential problems.

Yet the epicutaneous route for immunotherapy seems to produce the least number of severe adverse reactions out of all the options being developed, he told reporters at an unrelated press conference.

Studies with oral immunotherapy have suggested that most patients experience some adverse events, of which 5% to 10% are significant, and perhaps 12% of children will require epinephrine at some point (6% during maintenance dosing at home), he explained.

"But whether or not we're going to be able to get comparable protection as we get with oral immunotherapy we don't know," he said. "Those studies aren't far enough along."

Sampson is leading a , with peanut protein doses going up to 250 mcg with the patch treatment. A version for milk allergy is being studied as well.

"Epicutaneous is really early on," he told 番茄社区.

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