After a year, 46 percent of the low-dose group and 48 percent of the high-dose group could do that, but only 12 percent of those on the placebo patch could.
Children aged 4 to 11 had the best response. The patch had less effect on those aged 12 and older, the study authors said.
The results were published online Oct. 26 in the Journal of Allergy and Clinical Immunology.
The patch is based on the same concept as other anti-allergy treatments, aiming to engage the immune system to train the body to tolerate small amounts of the protein.
Other researchers have tested giving small oral doses of the peanut protein, but the NIH team of researchers noted that that regimen is difficult for about 10 percent to 15 percent of people to tolerate.
No serious reactions to the patch were reported, Plaut said. Most did report mild skin reactions, including itching or rash at the site of the patch.