Q&A: Omalizumab provides protective effect for multiple food allergies
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Key takeaways:
- Patients tolerated 600 mg of peanut protein and 1,000 mg of other proteins with treatment.
- Patients at risk for accidental exposure due to age and those with comorbidities may benefit most.
WASHINGTON — Patients with multiple food allergies experienced a protective effect against allergic reactions with omalizumab, according to an abstract presented at the American Academy of Allergy, Asthma & Immunology Annual Meeting.
In the OUtMATCH study, patients aged 1 to 55 years with allergies to peanut and two other foods confirmed by food challenges received omalizumab (Xolair, Genentech/Novartis; n = 120) or placebo (n = 60) for 16 weeks, followed by additional food challenges.
Two-thirds (66.7%) of the treatment group and 6.7% of the placebo group tolerated 600 mg or more of peanut protein at the end of the study period (OR = 28; 95% CI, 9.2-112; P < .0001).
The treatment group experienced similar results for tolerating 1,000 mg or more of tree nuts (OR = 9.53-21.9), milk (OR = 18.3), egg (OR = infinity) and wheat (OR = 21).
These reaction thresholds persisted or increased during the study’s open-label extension. Also, the treatment and placebo groups had similar safety outcomes.
The researchers noted associations between treatment success and higher total IgE, dosing every 2 weeks instead of every 4 weeks, smaller skin test sizes and higher tolerated doses during food challenges at baseline.
Healio spoke with Robert Wood, MD, FAAAAI, professor of pediatrics, Johns Hopkins University School of Medicine, to find out more.
Healio: What are the limitations of other current treatments for food allergy?
Wood: They’re extremely limited. The vast majority of patients just follow the age-old recommendation to try to avoid what they’re allergic to and carry emergency medications in the event of an accidental exposure. There are some patients being treated with oral immunotherapy, but it is a very small proportion of everyone with food allergy. There is only one FDA-approved product, and acceptance in the allergy community has been pretty slow.
We’re really left with an open playing field. There’s essentially no treatment, and oral immunotherapy is really something we look at very much as a food-specific treatment. But most of our patients don’t have just one allergy. They typically have more than one. So, if there was some approach that could provide some protection for patients with multiple food allergies, that kind of drug would have a special advantage.
Healio: How does omalizumab provide protection for multiple food allergies?
Wood: Omalizumab is referred to as an anti-IgE drug. IgE is the antibody made by people with allergies that drives allergic reactions. Omalizumab essentially is binding to the IgE so it can’t interact with the allergy cells and whatever food you get exposed to that lead to an allergic reaction.
Healio: How does omalizumab build upon other treatments?
Wood: For those who think avoidance is not working well for them, this would be an option for them to replace the avoidance. It doesn’t necessarily relate to or build upon the role of immunotherapy. Although there have been a lot of studies to show that if you provide omalizumab along with immunotherapy, it doesn’t make immunotherapy more effective, but it may make it safer. So, from that context, there may be some ways the drug is used, not per the FDA label, but the allergist might choose to use this drug as an adjunct to oral immunotherapy.
Healio: How was the OUtMATCH study designed?
Wood: The design is complicated overall. But on the other hand, the stage we’re presenting here is very straightforward. Stage 1 of OUtMATCH is a double-blind placebo-controlled trial comparing omalizumab with placebo. Participants had to be allergic to peanut and to at least two other foods. They had to undergo food challenges to peanut and the other foods to document that they were highly allergic to those foods. They then received the medication, which was given by injection every 2 weeks or every 4 weeks. They got that for 4 months, and then they repeated the same set of food challenges. So, the design of stage 1 was pretty straightforward, and changes in the amount of the food it took to cause a reaction was the primary endpoint.
Healio: What was the patient population like?
Wood: There were 180 patients, and 177 of them were regarded as pediatric, which means they were aged 17 years and younger. There was a nice breakdown of different age groups. One of the things that was special about this study was the opportunity to go down to age 1 year. We had about a third of participants who were aged 5 years and younger, about a third who were aged 6 to 11 years, and about a third who were aged 12 to 17 years.
Healio: Are there plans to include more adults in later phases of the study?
Wood: There are not. The reason for that is that the FDA approval was granted for age 1 year and older. Adults were included in the approval.
Healio: Are there any topline results you would like to spotlight?
Wood: The drug worked very well. If you compare peanut, to which all participants had to be allergic, 67% got a high level of protection, and 33% did not. On the other hand, many of those 33% were protected compared with where they started at baseline. That efficacy was very similar for each of the foods studied, which included milk, egg, wheat, cashew, walnut and hazelnut. The smallest numbers were for wheat and hazelnut, but they were still far superior to placebo. The really impressive results come out when you have larger numbers in the sample size.
Healio: Now that the FDA has approved omalizumab for this treatment, how do you expect it to start impacting care?
Wood: We think it’s going to be a real game changer for a lot of patients. We’ve had patients treated with omalizumab for other conditions such as asthma, and we’ve been able to use it in part to control their food allergy. Those people have generally found this to be a really big advantage in their lives.
When we think about who this might appeal to most, or who might best be treated, there are a few things that I think will stand out. One of them will be that the more foods you’re allergic to, the more appealing the drug may be. That’s especially true if you’re allergic to such things as milk and egg, which are extraordinarily hard to avoid.
Somebody who has peanut allergy is more likely to say that they are doing well with avoidance because peanut is relatively easy to avoid. Now, accidental reactions happen. But it’s not like what we see with things like milk and egg, where it’s very hard or impossible to eat out in a restaurant or travel without a kitchenette. We think in that population, when we’re really dealing with many, many food allergies, it’s going to be especially appealing.
Healio: Are there any other patients who would be a good fit for this treatment?
Wood: In addition to patients with multiple food allergies, there are certain age groups where we worry more about accidental reactions — preschool and then high school and college. In my family clinic, we had a family who said their 12-year-old has been doing great with his avoidance. He’s not stressed by it. But on the other hand, they’re pretty sure he will be on omalizumab sometime between high school and college, because they really anticipate higher risk at that time.
The third factor is the level of anxiety. There are families who are dealing with food allergy very, very effectively. Then there are others who are paralyzed by the fear of that reaction. This will make a big difference for them.
There’s one other unique thing that is going to influence some people to be treated or not treated. And that has to do with comorbidities. Take someone who is on the fence about being treated, and they’re doing well with their avoidance, for the most part. But they also have asthma. The asthma was not bad enough to require omalizumab.
But omalizumab doesn’t only work on bad asthma. It actually works really well on less severe asthma too. If that individual has asthma, and a lot of environmental allergies, the thought of being able to get a shot every 2 weeks or every 4 weeks, and potentially drop their daily antihistamines and steroids or reduce them, is very appealing.
It’s a reality of the drug that it does match all these different things. I think that will be a tipping point for some families. It will be interesting to see how it plays out. I think that will be another factor that drives some people to say, “Let’s get treated.”
Healio: What is the next step in this research?
Wood: Stage 2 is a comparison of longer-term omalizumab compared with multi-food oral immunotherapy. That’s one of the real questions that everyone at this meeting has. What may be best for my patients? Should there be some priority given to one treatment or another? This will really help to answer that question over a longer period of time. What are the pros and cons of this one type of therapy that is really meant to protect against small exposures and another one that potentially might have more long-term benefits, but also has a lot more risk and is a lot more cumbersome?