Efficacy of baked milk oral immunotherapy in baked milk-reactive allergic patients

Background: Patients with IgE-mediated cow's milk allergy who are nonreactive to baked milk (BM) can be desensitized with BM to promote tolerance to unheated milk (UM). Objective: We sought to test whether patients who are BM reactive can progress in BM oral immunotherapy (OIT) and become desensitized to UM as well. Methods: Fifteen patients (>4 years) who previously failed to complete our milk OIT program were enrolled into the BM OIT protocol. A dose of BM (180 degrees C for 30 minutes) which was less than the eliciting dose was increased 50% monthly while under medical supervision until the primary outcome dose of 1.3 g/d BM protein was achieved. Basophil reactivity and milk protein-specific IgE binding were analyzed at the first round of BM OIT therapy (T-0) and at 12 months of BM treatment. Results: In terms of the primary outcome, only 3 (21%) of 14 patients tolerated the 1.3 g/d BM dose. Although some patients initially progressed in BM OIT, 8 of 11 failed because of IgE-mediated reactions. Three did not complete the program because of non-IgE-mediated factors. An increase in challenge threshold to UM was noted in patients continuing until 12 months (P = .003), including those among whom reactions precluded continuation in the program. Patients (n = 3) who successfully reached maintenance had decreased milk-specific IgE reactivity. Furthermore, the mean difference at T-0 between induced HM and UM percentages of CD203c expression was significantly lower in patients who successfully completed BM OIT than in those who did not (211% vs 4.4%, P = .0002), which is consistent with their decreased clinical reactivity to BM. Conclusions: Although use of hypoallergenic BM in OIT is a promising therapy, care must be taken before its administration in BM-reactive patients because of the risk for anaphylaxis and only limited increase in challenge threshold attained.