Identifying the Biomarkers for the Treatment of Severe Asthma - Episode 8
Neal Jain, MD, FAAP, FAAAAI, FACAAI: We’ve heard a lot about asthma already, and we’ve alluded to sort of these patients that have more difficult-to-treat asthma, and these inflammatory pathways that are involved, and these guidelines. There’s actually another guideline that came out in December, the “[Difficult-to-Treat and] Severe Asthma” pocket guide from GINA [Global Initiative for Asthma], which is another guideline to help us sort of conceptualize how we identify these patients. But that guideline asks the question of: What’s the difference between a difficult-to-treat asthmatic versus a severe asthmatic? And then building upon that, when you see these patients, and someone has truly severe disease, how do you target that disease? What are the pathways we think about, etc? And Nic, I’m going to have you lead off with this.
Nicola A. Hanania, MD, MS: I think you’re bringing a very important point. People often confuse uncontrolled asthma with severe asthma. They’re 2 different things. While you can have controlled severe asthmatics, you also may have uncontrolled severe asthmatics. And some patients with uncontrolled asthma don’t have severe asthma. In fact, the most common cause of uncontrolled asthma is poor adherence—misuse of inhaler devices, not dealing with triggers or comorbidities. So that’s uncontrolled, in general. That’s about 40% to 50%. Questionnaire studies in the United States show that about 50% of asthmatics, if you give them an ACT [Asthma Control Test] score or a questionnaire, have uncontrolled asthma. They don’t have severe asthma.
Now, once you treat these—deal with comorbidities, deal with triggers, deal with compliance, deal with your inhaler devices—or once you’ve checked this off and the patient requires a high-dose inhaled steroid and another controller to control his or her disease, or requires an oral steroid to control his or her disease more than 50% of the time in the preceding year, that’s severe asthma by definition. That’s about 5% to 10%. It’s a small number, but those are the ones, as you all know, that cost the system a lot, in terms of not only money but morbidities. So severe asthma is a very small group of patients. Once you’ve done all the things on the checklist, if they still require a high dose of the inhaled steroid and a controller to control their disease, or need oral steroids more than 50% of the time, that’s, by definition, severe asthma, at least based on the guidelines for severe asthma.
Neal Jain, MD, FAAP, FAAAAI, FACAAI: So once we’ve identified a patient, then I guess that becomes the next question. If you’ve identified this patient who has severe disease, what do you do?
Aidan A. Long, MD: And I think that’s an important question. I just want to reiterate what Nic said. There’s a distinction between the difficult-to-control asthmatic and the asthmatic who needs a novel biologic therapy. Are they using their medications? Are there comorbidities? Are they adherent? Have we got the wrong diagnosis? Is the environment adverse? If you go through that checklist, the studies show that you’re down to somewhere near 10%, perhaps even less than that. One study says 4%, and 1 study said 3%, so it’s a small number. And because it’s difficult to control, I think we need to break that knee-jerk assumption that, therefore, they need a biologic.
Neal Jain, MD, FAAP, FAAAAI, FACAAI: Absolutely.
Aidan A. Long, MD: And I think that’s the important point to make here.
Bradley Chipps, MD: That’s the reason why the placebo arms in the biologic studies show such a good response, because those patients actually take their medicine.
Neal Jain, MD, FAAP, FAAAAI, FACAAI: That’s absolutely right.
Bradley Chipps, MD: And placebo turns out to be pretty good medicine.
Neal Jain, MD, FAAP, FAAAAI, FACAAI: Absolutely. Enforcing adherence. It turns out to be a good medicine, right?
Nicola A. Hanania, MD, MS: Yes.
Transcript edited for clarity.