Combining omalizumab (Xolair) with milk oral immunotherapy (OIT) makes treatment significantly safer, but does not increase the efficacy of OIT, according to findings of a newly published study by a team of researchers from the Johns Hopkins University School of Medicine, Stanford University and the Icahn School of Medicine at Mount Sinai.
Published last week in the Journal of Allergy and Clinical Immunology and funded by a grant from the National Institute of Allergy and Infectious Diseases (NIAID) and a supplementary grant from FARE, this was the first double-blind, placebo-controlled trial combining milk OIT and omalizumab, a drug used to treat uncontrolled allergic asthma and chronic idiopathic urticaria (hives that have no known cause and last more than six weeks).
In this study, 28 patients with milk allergy received omalizumab injections and 29 patients with milk allergy received a placebo every two to four weeks for the first 16 months. Participants in the study were between the ages of 7 and 32. They began open-label milk OIT in the fourth month and continued to receive escalating doses of milk protein. They were required to reach a minimum maintenance dose equivalent to about one tablespoon of milk. Daily maintenance dosing continued through month 28, at which time omalizumab was discontinued. Participants who passed an oral food challenge continued milk OIT for eight weeks, after which OIT was discontinued, and those participants were re-challenged at month 32 to determine whether they had achieved sustained unresponsiveness – the ability to tolerate a food without continuing OIT.
“Virtually all safety measures were markedly improved in the omalizumab group. The subject withdrawal rate decreased and the time needed to achieve maintenance dosing was shorter,” lead investigator Dr. Hugh A. Sampson of the Icahn School of Medicine at Mount Sinai said in a news release from the American Academy of Allergy, Asthma & Immunology (AAAAI).
According to AAAAI’s news release, participants who had received omalizumab experienced fewer adverse reactions as measured by the percentages of OIT doses per patient provoking symptoms (median: 2.1 percent in omalizumab group versus 16.1 percent in placebo group), OIT dose-related reactions requiring treatment (median: 0.0 percent in omalizumab group versus 3.8 percent in placebo group), and OIT doses required to achieve maintenance (median: 198 doses in the omalizumab group versus 225 doses in placebo group).
The study reports that 13 participants passed the final oral food challenge from the omalizumab group and 10 passed the oral food challenge from the placebo group. Other participants either withdrew from the study or failed oral food challenges and discontinued milk OIT. Both groups demonstrated similar rates of sustained unresponsiveness or desensitization, showing that omalizumab did not increase the outright efficacy of the OIT.