Kidney Disease-Associated Pruritus and Managing Prurigo Nodularis: Treatment Pearls From Raj Chovatiya, MD, PhD

The 2023 World Congress of Dermatology meeting in Singapore brought together more than 10,000 global dermatology experts within the past week.¹ Clinicians, scientists, health care professionals, and industry partners met to discuss and reveal the latest advancements in dermatology across the globe. At this year’s Singapore meeting, Dermatology Times’® editorial advisory board member Raj Chovatiya, MD, PhD, was selected to present treatment pearls related to chronic kidney disease-associated pruritus and managing prurigo nodularis with biologic therapy.

Chovatiya, an assistant professor of dermatology, director of the Center for Eczema and Itch, and medical director of the clinical trials unit at the Northwestern University Feinberg School of Medicine in Chicago, Illinois, spoke with Dermatology Times to review his first session, “Chronic Kidney Disease-Associated Pruritus,” as well as his moderated industry session, “Charting a New Course in Prurigo Nodularis: Changing the Treatment Paradigm With Biologic Therapy.”

Transcript

Chovatiya: Hi there, my name is Dr. Raj Chovatiya, I'm an assistant professor of dermatology, director of the Center for Eczema and Itch, and medical director of the clinical trials unit at the Northwestern University Feinberg School of Medicine in Chicago, Illinois. I'm also on the editorial advisory board for Dermatology Times.

Dermatology Times: What pearls did you share during your presentation, "Chronic kidney disease-associated pruritus?"

Chovatiya: This past World Congress, I had the pleasure to discuss a topic that, you know, we don't always get to put on the center spotlight, chronic kidney disease associated pruritus. Now I know what you're thinking, I'm a dermatologist, I don't need to think about the kidney. It's all about the skin. And you're partially right. But I think it's really important for us to realize that there's a lot of patients out there coming to see us in the dermatology clinic that have a whole host of other medical conditions going on. And when people feel like there's something affecting their skin, whether it's how it looks or how it feels in the case of itch, they're naturally going to think of their skin specialists to really help get to the bottom of things. And so, this was kind of the theme of my lecture at World Congress. I had a chance to review the fact that chronic kidney disease is common. There are so many people worldwide that have this problem. There's a lot of different skin changes that we can think about and skin symptoms in general, itch is probably the most common one that can occur in people particularly as they advanced to later stages of chronic kidney disease or actually end up in end stage renal disease requiring dialysis, either hemodialysis or peritoneal dialysis. What studies have shown is maybe upwards of even 90%, if not more of individuals have some degree of itch associated with their kidney disease. Now, you don't have to necessarily be on dialysis to actually experience itch. This is a common misnomer, but really any patient affected by kidney disease can actually have an itchy sensation.

We haven't really gotten to the bottom of pathogenesis here. There's a lot of conflicting theories. Could this be changes in the immune profile and inflammation? Could this potentially be related to changes on a tissue level different circulating serum factors? Could this potentially be related to the actual process of dialysis itself? There are a few myths though, that we've managed to bust over time. Number one, this probably is not a circumstance where if you just dialyze more, you can fix the problem for people that require dialysis. Number two, this probably isn't all just parathyroid hormone, calcium, and phosphate. And number three, this probably isn't just all driven by dry skin, the thing that we hear all the time, you fix the xerosis, the problem will get better. This leads into my last part of the talk of talking about what we can actually do to manage this condition. It's challenging, but optimizing moisturization is a good place to start. And then all the systematic reviews that have been done on this topic suggest that most of the data here exists for gabapentin and pregabalin, followed by kappa opioid receptor agonists. Now, in that last category, we actually saw the approval of our first directed therapy for this condition in the past couple of years in the US medication known as DFK, or difelikefalin. This is a medication that's dosed through IV and is right now intended for those undergoing hemodialysis, modulates the kappa opioid receptor to help reduce itch. And that's what randomized clinical trials have demonstrated, kind of a game changing medication in this space. Now DFK is being studied in a few other different ways. And hopefully we'll be seeing an oral version soon for individuals that are not necessarily hemodialysis dependent and unrelated to the kidney altogether, we'reactually going to potentially be seeing some approvals for itch associated with atopic dermatitis, and notalgia parasitica, just to name a couple.

Dermatology Times: What highlights did you share while moderating "Charting a new course in prurigo nodularis: Changing the treatment paradigm with biologic therapy?"

Chovatiya: Prurigo nodularis is having a bit of a moment and it was kind of the same at this past World Congress in Dermatology. Now, it's a disease state where there's still a lot of mysteries and unanswered questions. But with the approval of targeted therapy in the case of dupilumab and potentially approval of more therapies very, very soon, we're beginning to have tools to be able to answer these questions. I had a lot of fun in moderating a discussion with the experts where we went back and forth in a team challenge-based model interacting with the audience to show what we know and don't know about this condition. What I can say is number one, we know that the itch associated with prurigo nodularis can be unbearable for our patients, it's really central to the entire reason why we need to have better treatments. Secondarily, we know that there's essentially a combination of neurological mechanisms and immune mechanisms that underlie the center of this disease. The neuroimmune axis is really what we need to be targeting in order to get improvement for our patients. And finally, based on data that dupilumab showed us through randomized clinical trials, IL-4 and IL-13 appear to be two important cytokines that form the basis of type two inflammatory dysregulation that we think about in the case of prurigo nodularis.

Dermatology Times: What did you enjoy most at this year's World Congress of Dermatology in Singapore?

Chovatiya: It was such an honor to be invited to participate in the World Congress of Dermatology this past year, a chance to make so many new friends, see some old faces, and hear what's going on all around the world. One of my favorite things is we oftentimes get caught in this microcosm of what's going on in your host country. And it was so cool to hear about the different ways that we're all approaching some of the same diseases. The more forums we have like this, the better off we're going to be for all of our patients. So just can't wait for the next one.

[Transcript edited for clarity]

Reference

1. Singapore hosts the 25th World Congress of Dermatology – the first in Southeast Asia featuring 10,000 global experts to discuss new developments in skin research and treatment. World Congress of Dermatology. June 15, 2023. Accessed July 6, 2023.https://www.wcd2023singapore.org/wp-content/uploads/2023/06/WCD2023_Press_Release_Announcement.pdf