A skin patch that delivered a high dose of peanut protein reduced peanut sensitivity in children and adults with peanut allergy, findings that warrant a phase 3 trial, according to a study published in JAMA.
The Phase 2b trial included 221 peanut-allergic patients (age 6-55 years) from July 31, 2012 to July 31, 2014. Patients completing the trial participated in a 2-year extension using the most effective peanut-patch dose to assess efficacy for up to 36 months; extension study completed September 29, 2016.
The study randomly assigned participants to a peanut patch containing 50 µg, 100 µg or 250 µg of peanut protein or placebo for 12 months and measured the percentage of treatment responders in each group vs placebo patch after 12 months. Patients were considered treatment responders if it took 1,000 mg or more of peanut protein and/or 10-times the pretreatment amount of peanuts to trigger an allergic reaction.
There were more treatment responders among patients given the 250-µg peanut patch (n = 28; 50%) than among patients given the placebo patch (n = 14; 25 percent). There was no difference between the placebo and 100-µg patch. The percentage of patients with one or more treatment-emergent adverse events (largely local skin reactions) was similar across all groups in year 1.
These findings support testing of the 250-µg peanut patch dose in a phase 3 trial involving patients with peanut allergy, the authors concluded.