Recommendations for treating plaque psoriasis with newer biologic therapies and factors that warrant a switch in therapy, either using another biologic of the same class or moving to a different class.
Andrew F. Alexis, MD, MPH: Now, Dr Blauvelt, Dr Boh touched on comorbidities. I'm curious to hear, in your practice, how do comorbidities factor into your decision for treatment. If you'd like to speak to the AAD [American Academy of Dermatology] and National Psoriasis Foundation guidelines with respect to comorbidities and how they may influence choice of treatment, please go ahead.
Andrew Blauvelt, MD, MBA: Sure. The first thing I wanted to talk about is to highlight that I'm not stuck on a BSA [body surface area] of 10% or more. I tend to practice going to a biologic based upon body surface area, yes, presence or absence of psoriatic arthritis, whether the disease is in special areas, like genital psoriasis or palm and sole psoriasis, and whether they have failed topical therapy. It's a little bit broader use of biologics compared to just strictly the BSA criteria.
I find that I can get a drug for most of my patients that meets one of those criteria: failure of a topical, BSA greater than 10%, or special area involved. That fits with some new recommendations that the International Psoriasis Council has put forth as far as treating patients. Comorbidities absolutely influence my choice. The big one, the most common one is psoriatic arthritis [PsA]. In my practice, 40% to 50% of patients have psoriatic arthritis. It's higher than the often quoted 25% to 33% or so. It's a really common thing that I see. I have a broad definition of PsA.
It's really not a great term, psoriatic arthritis, because we know that morning stiffness is part of psoriatic arthritis. We know that enthesitis and dactylitis are part of psoriatic arthritis. We know that fatigue is part of psoriatic arthritis. If patients are having any of those things, I call that PsA just because we really don't have a great term for prominent morning stiffness without joint inflammation. Basically, I think it is psoriatic arthritis. For patients with that comorbidity, my class of choice is actually IL-17 blockers, so a little bit different than what Erin just mentioned.
I consider TNF blockers as the second line for my patients with PsA. I say that because the data are comparable in joint data with TNFs and IL-17s. Yet, then we also see the skin data being better for IL-17s and the safety profile being better. When I take all of these things together, that's the class I would say is my class of choice for a patient with psoriatic arthritis. The other major comorbidity for me is heart disease. It's common with more severe psoriasis and less common with more mild disease. Anybody over 10% body surface area is going to be at risk for heart disease.
We know that through lots of studies over a long time. Here, I don't necessarily go with class, I try to think about clearing psoriasis to zero because if somebody has a lot of body surface area, I want to get them lower, to lower their risk for heart disease. The best lowest mark would be zero. I'm looking at highly effective treatments, the best IL-17 blocker, the best IL-23 blocker, are kind of where I'm at for trying to get people to complete clearance for that type of patient. Obesity is another really common one that plays into things.
I'm not going to use a TNF blocker for patients who are obese. I think the data are really good as far as their efficacy not being good in the obese population. We see better efficacy data for the newer biologics. Again, probably an IL-17 or IL-23 for me for the patient who is obese. Some comorbidities are not going to change my view with biologic therapy. Things like hypertension, diabetes, other aspects of metabolic syndrome, are not going to change much.
They don't really factor too much for me in biologic choice. Obviously, the psychiatric comorbidities, depression and anxiety, which I do agree with what Erin said earlier, are really common in our population. We often, though, will see when patients are clearing their skin, improvements in the depression scores, improvements in quality of life. So again, I'm thinking of highly effective drugs. At the end of the day, I'm in this IL-23 blocker, IL-17 blocker grouping. I like to use the newer ones. I'm not using many TNF blockers at all now. It's pretty rare for me to use a TNF blocker. I'd say I favor IL-17 blockers if the patients have psoriatic arthritis. I favor an IL-23 blocker if the patients don't have psoriatic arthritis. That’s where I am now.
Andrew F. Alexis, MD, MPH: I'm going to turn it over to Dr April Armstrong. April, I'm going to ask for abrief comment on a practical question, which is, what goes into your decision to change therapy? You've got a patient on follow-up; they've already been on a biologic, and you're assessing them. What decisions go into switching from one biologic to another?
April W. Armstrong, MD, MPH: I would say Andrew, as Erin and Andy already said, choosing the best biologic that's fitting for the patient is the first important thing. Then what happens for me, is looking at the patient to see if they have responded to the biologic is really important. It's very important for me as well to try to treat the patient to clear, if possible. In general, I would say, if the patient is not responding after 6 months, and I wait at least 6 months, some say they wait 3 months, but I typically wait at least 6 months.
The reason is that some are just late bloomers in terms of response. I would then switch them within the class if there are comorbidities that drive my decision-making process. For example, if they have active PsA and they had been on an IL-17 before, and I think switching to another IL-17 would address not only their psoriasis, but also their PsA well. With regard to switching patients from one biologic to another class, I would say that that is definitely one of the key options I think about. Especially when someone is a primary failure on the biologic, meaning that if they have never responded well in the first place, then I think that the immunologic pathway that drives their psoriasis may be very different from the therapy that I'm trying to target. In those cases, if it's not going to affect their treatment of their other comorbidities, then I would consider switching them to a different class.