Omalizumab improves efficacy of oral immunotherapy for multiple food allergies
Combining an initial 16-week course of the monoclonal antibody omalizumab with oral immunotherapy (OIT) significantly and safely improves desensitization to the offending foods compared with OIT alone in children and adolescents with multiple food allergies, a new study found.
“[N]o OIT is currently approved for treatment of single food allergies, let alone for multiple food allergies … Attempting to treat individuals with multifood allergies with sequential single OIT to each of their offending foods would result in many years of treatment,” said the researchers. “[Our study] shows the potential benefits of using omalizumab to facilitate multifood desensitization to a variety of food allergens in a shortened period of time.”
At week 36, significantly more omalizumab-treated participants passed the food challenge to 2 g of at least two of their offending foods than those receiving OIT alone (odds ratio [OR], 10.0; p=0.0044). Those who could safely tolerate 2 g of food protein were also able to tolerate 4 g of at least two foods in the same challenge. [Lancet Gastroenterol Hepatol 2017;doi:10.1016/S2468-1253(17)30392-8]
“For many of these food proteins, 4 g represents an average serving (eg, about one tablespoon of peanut butter), and the ability to increase an individual’s threshold of food ingestion to a serving of protein is important for their nutrition and overall quality of life,” explained the researchers.
Based on stratified analyses, omalizumab was more likely to benefit participants who were older (aged ≥8 years; OR, 42.0; p=0.0068) and who had highest allergen-specific IgE of ≥15 kU/L at baseline (OR, 30.0; p=0.0024), while no significant difference between treatments was observed in subgroups younger than 8 years (p=0.50) and baseline highest allergen-specific IgE of <15 kU/L (p=0.85).
The omalizumab + OIT group achieved the maintenance dose of 2 g for each food at as early as 12 weeks compared with 20 weeks in the OIT-alone group (HR for achieving maintenance dose, 5.36; p=0.0011).
“This compressed timing is another advantage conferred by omalizumab, because it suggests that less frequent visits for updosing would be required … [and] thus potentially improving the chances of adherence,” noted the researchers.
“Minimizing adverse events [AEs] during updosing might also enhance long-term compliance,” they added.
No serious or severe (grade ≥3) AEs were reported during the study. The most common AEs in both treatment groups were gastrointestinal events. The median per-participant percentage of OIT doses associated with any AEs was lower with omalizumab than with OIT alone (27 percent vs 68 percent; p=0.0082). Specifically, lower median per-participant percentage of OIT doses associated with gastrointestinal (22 percent vs 54 percent; p=0.044) and respiratory AEs (0 percent vs 1 percent; p=0.023) was observed in the omalizumab vs OIT-alone groups.
The double-blind phase II trial randomized 48 participants aged 4–15 years with multifood allergies in a 3:1 ratio to omalizumab or placebo, in addition to multifood OIT to 2–5 foods. Another 12 untreated patients who were not randomized to any treatment were also included as controls.
According to the researchers, the findings showed that multifood desensitization can be safe and effective “in a highly atopic population” (high food allergen-specific IgE levels and reactivity to relatively low cumulative doses [≤500 mg of protein] of each offending food at baseline) at risk for fatal or near-fatal food allergic reactions.
“A potential concern with using omalizumab is that participants might be at risk for allergic reactions once omalizumab treatment is stopped; however, our data showed no increased frequencies of adverse events after discontinuation of omalizumab and no increased frequency of AEs during omalizumab treatment,” they added.