Douglas Mack, MD: Considering Food Allergy Treatment, Testing Options

The benefits of a growing food allergy market are obvious: with immunotherapies reaching regulation, there’s options to treat patients. But challenge is more subtle: physicians now have a responsibility to consider all the patients, and to train patients on their options.

In an interview with MD Magazine® while at the American College of Allergy, Asthma & Immunology (ACAAI) 2019 Scientific Meeting in Houston, Douglas Mack, MD, a pediatric allergist with McMaster University, explained why this responsibility is easier said than done—and how come, no matter what, the ultimate treatment goal comes down to the patient’s interests.

MD Mag: Why are patient-set goals the ultimate outcome in allergy immunotherapy?

Mack: We will have options, and I think I may need to use different options based on the patient's goals, based on the approaches, or how they're doing during the therapy.

I may have to add something on, based on whatever, and it is possible that we find that the safest way to do this approach is with an adjuvant. At this point, we don't have that, but for now, I think it's all about the patient goals. And I agree—ironing those out from the very beginning.

You know, one of our patients said to me—very early on when I started, after the six-month build up phase where you can have increased the dose—they said to me at the end, ‘So we can get rid of the EpiPen now?’ And I realized that was their goal, and I hadn't discussed it with them. Whether I got them there with using an adjuvant, or I got them there doing whatever, it didn't matter—their goal was to get away from the EpiPen, and we did not meet that goal. And all that it would have taken was a simple discussion.

So now we have completely structured our approach indifferently, so that we do understand that. There's lots of fancy ways to do this, but if I'm not meeting that family's goals, I may as well not use anything—I'm heading down the wrong path.

MD Mag: Are oral food challenges necessary for diagnosing an allergy?

Mack: The fun of the debate I think is, we want to make sure that if I am picking a therapy that is costly and that is labor-intensive and is potentially lifelong, I need to know whether those patients are truly allergic.

I think that there is a lot going into this, and our diagnostic criteria and our standards are actually not great. And I think part of that, for example is the fact that for years we were able to just say, ‘I can see you in 2 years, we'll see what happens.’ And we have never had to commit.

Does that make sense? We've never had to commit, because avoidance is relatively easy—not easy, I shouldn't say that. I don't want to minimize it, but it's a relatively neutral path. But a surgeon, for example, could never say, ‘You know what? I think you have appendicitis, but maybe not. Come back to me in 2 years. I'm not quite sure.’ Before they open that patient up, they need to know what their diagnosis is.

And I think that the same thing applies for us, but we haven't had that pressure before this time. There's another side to it as well, and I think I was able to argue the ‘con’ side last night, saying that potentially, oral food challenges aren't necessary for everybody. And I think we do have some diagnosis centers that are actually not bad.

There is an increase in risk of reaction when we're doing these oral challenges prior to doing immunotherapy. But at the end of the day, if I discuss this with my patients, and their goal is that they don't want to do the oral challenge, and they won't do immunotherapy if I had insisted in them doing an oral challenge, then during that shared decision-making meeting we can we can address that and determine if this is really what is aligning with their goals.

It was a fun discussion to have. I don't think there's a right answer here. We certainly are inclined to do far more oral food challenges because of this, and we have some data—kind of interesting data that when you look at the number of kids that have been sent to us specifically for OIT for peanut under the age of 6, only 43% of them actually react.

Fifty-seven percent of those kids did not need OIT, and all I had to do is an oral food challenge. But once again, I will counsel my families on that. I'll say, ‘Look, these are your odds, given this bloodwork, given the skin testing, given your history. You may actually not have to do this at all.’

But if in the end, the family decides that they don't want to do an oral food challenge, and that is the factor that will determine whether they do immunotherapy—I haven't done my job if I deny them the possibility. So it's an interesting discussion, I think.