Jerry Bagel, MD, MS: Here’s the question of the year. When might you switch from one biologic agent to another within the same class? And when is it beneficial to switch from a biologic in one class to another?

Alexa Hetzel, MS, PA-C: If you look at all of the clinical trials, all of the data that we do, people usually look to week 16 and week 24. Those are usually our primary and secondary end points. With TNFs [tumor necrosis factor inhibitors], they work so quickly that we should expect to see some sort of improvement by 12 weeks, once their loading dose is done, because they get so much right away. At that point, we probably won’t see too much skin improvement. Joints can be a little different; scalp and nails can take longer. With the IL-23s [interleukin-23 inhibitors], week 24 is when we reevaluate our treatment goal. Obviously, we’re overachievers, so I would love everybody to be 100% clear, but if I can get them to 90% clear, I’m pretty happy with that too. If patients are happy with a little patch on their knee and they’re happy on the drug, then I’m OK with that as well. But each biologic in each class is different. They do not bind to the same subunit, or the same receptor, which is why they are a different drug in each class. Do you have that same experience?

Jerry Bagel, MD, MS: Yes. I’m not afraid of switching within classes, but I probably switch initially out of a class if I can because I figure that if this IL-17 didn’t work, or if this TNF didn’t work, then why go to another TNF? Sometimes, I can’t do that. If somebody is on Cosentyx [secukinumab] and they’re not doing great but their joints are OK, I would say I’m willing to switch to ixekizumab, Taltz, because it’s a different molecule. It has 80 times the binding affinity to IL-17, and therefore, it’s worth a shot, especially if they have psoriatic arthritis, because I’m not so sure that the IL-23 class is going to work as well for the joints. I would go within that class. But for others, I like switching to another class if I have that opportunity.

Alexa Hetzel, MS, PA-C: Will you let patients on IL-17s ride it out a little longer if they have psoriatic arthritis, maybe add a topical?

Jerry Bagel, MD, MS: Yes, especially if it helps their arthritis, and their skin is not doing as well, I definitely could use a topical. There are some new topicals for psoriasis. I would definitely push it out a little longer until about 24 to 28 weeks. It’s possible for that group. Most of the biologics max out at about 24 weeks, but not Taltz. Even secukinumab, Cosentyx, maxes out at 24 weeks. You try to get that person better, but I must see some benefit. I must see like 75% benefit along the way, otherwise, I’m going to ask people.

What I get a lot from other dermatologists, when I ask them when do they switch, they say, “If the patient’s happy, I’m happy.” I’m thinking, “If the person has 10% body surface area affected, are you still happy”? They go, “If the patient’s happy, I’m happy.” I say, “If somebody has pustular cystic acne on doxycycline, are you happy?” They say, “No, I’ll switch them to Accutane.” I say, “Why not move it here?” There’s a psychological scar of having psoriasis. Switching is a big deal. The other thing to be concerned about with switching is to make sure patients are being compliant and they’re not stopping or decreasing the frequency of taking medications.

Transcript Edited for Clarity