September 27, 2021
8 min read
Although multiple therapies, including systemic and biologic treatments, are effective in treating psoriasis, topical agents are an important component of psoriasis management, according to April W. Armstrong, MD.
“Topical therapy has always been a keystone of therapy for patients with more limited psoriasis,” Armstrong, professor of dermatology and associate dean at Keck School of Medicine at USC, told Healio.
April W. Armstrong
To address the significant advances in research made in topical therapy, the American Academy of Dermatology and the National Psoriasis Foundation released joint guidelines on the use of these agents in 2020. In addition, the guideline authors recognized the growing popularity of alternative medicine and sought to discuss its role in psoriasis management.
In an interview with Healio, Armstrong, who helped author the guidelines, discussed some of the key recommendations regarding use of topical agents and alternative medicine as well as which tools may be most useful for gauging psoriasis disease severity.
Healio: What prompted drafting the guidelines?
Armstrong: First, topical agents have always played a role for patients with more limited psoriasis, so drafting and updating of the previous guidance on topical therapy was necessary to really reflect development in this exciting area.
Second, there have also been several different developments in terms of alternative therapies or approaches to treating psoriasis. Consequently, the guidelines committee felt it was necessary to address alternative medicine to better inform our clinicians, who will likely be asked questions about these treatments, as well as benefit the community in general.
Finally, the third part of the guidelines focuses on different psoriasis disease severity measures. Again, there has been tremendous development in this area, so we thought it was important to review these measurements and discuss their relevance in the clinical setting as well as the trial setting. This is important to help us monitor our patients’ psoriasis journey, but we also hope it will be informative for clinical trials as we evaluate different therapies.
Healio: What are the most important recommendations with respect to topical therapies?
Armstrong: We covered a number of different areas in our section on topical therapies. All are significant, but I will highlight two that are particularly important.
First, we emphasize that topical steroids remain an effective and safe therapy for many patients with mild to moderate psoriasis. This is important because our patients often come across information saying that we still need more research concerning the benefits and side effects of topical steroids. After evaluating rigorous literature, the committee believes topical steroids still play an important and major role in management of limited psoriasis, and when used appropriately under the direction of dermatologists, they can still be quite effective.
Second, we introduced the concept of proactive management, which arises from the understanding that psoriasis is a chronic disease that tends to occur and recur in the same areas for a person. This strategy involves treating psoriasis plaque to clear or almost clear during a flare and then applying a topical non-corticosteroid, such as a vitamin D analog or calcineurin inhibitor, to the area where the patient often experiences flare. However, instead of applying the treatment every day, the patient would do so maybe twice a week. This approach can reduce the number of flares as well as reduce the amount of medication that a patient is likely to use in the long term, so it is important that both clinicians and patients be aware of this strategy.
I would also like to mention some “oldies but goodies” in terms of treatment. For instance, long-term studies have shown that topical vitamin D analogs are still very safe and can typically be used in larger quantities — potentially up to 100 g per week — in adults. We also specifically reemphasized that calcineurin inhibitors, such as tacrolimus or pimecrolimus, also remain safe when used topically. Back in 2005, the FDA added a boxed warning to calcineurin inhibitors regarding the risk for lymphoproliferative disorder. However, this was related to systemic exposure in animals, and, to date, there is no signal or safety concern with the topical use of calcineurin inhibitors for psoriasis.
Finally, the guidelines address the use of combination topical therapy, which typically combines a topical steroid with a non-steroid agent, such as a topical vitamin D analog or a topical keratolyic agent. The advantage of many of these topical combination therapies is that the effects are quite synergistic, meaning they are generally more effective than either ingredient alone. Additionally, they often only require once daily dosing, so adherence is usually good among patients.
Healio: What do the guidelines say regarding the use of topical therapies in combination with biologic or systemic therapies?
Armstrong: Topical therapies make a good adjunct to biologic therapies or oral systemic therapies. For instance, a patient may be on a primary systemic agent — be it a biologic or oral systemic therapeutic agent — and may not achieve clearance to the degree that they would like. This would be a great opportunity to add a topical therapy to help reduce psoriasis severity in the hard-to-treat areas, such as the lower extremities. Often, we do not have the luxury of being able to switch a patient to another biologic due to their insurance or other barriers to access, in addition to the fact that they are reaping significant benefit from their current biologic. Therefore, the strategy here is to intensify topical treatment in those localized areas so that the patient can achieve clear or almost clear skin and be able to enjoy their life without feeling uncomfortable about their skin. This type of combination therapy is a good option, especially when the patient is achieving relatively good control of their psoriasis with the primary systemic agent.
Healio: What would you say are the most important recommendations regarding alternative medicine?
Armstrong: We covered several different topics in our section on alternative medicine and I encourage readers to review all of them. However, I will highlight a few that I believe are interesting.
One area that we covered in the guidelines is traditional Chinese medicine. Several studies have shown that traditional Chinese medicine yields some benefit in psoriasis, but most of these studies were not standardized in terms of measurements or methodology, which made it difficult to synthesize the data. In addition, traditional Chinese medicine is often an umbrella term used to describe various types of therapies, so we need more data and probably specialists in herbology to weigh in while we evaluate some of those data the next time around.
We also looked at a few other agents. Aloe vera and St. John’s wort, for example, have both shown some efficacy in patients with mild psoriasis. Again, though, we don’t have large studies with alternative medicines, and it would be a luxury to even have controlled studies, so although we recognize there may be some benefit to using these treatments in some patients, by and large, alternative medicine should really be considered as an adjunct to FDA-approved therapies. The reason for this is that the evidence for FDA-approved therapies is very robust while the level of evidence that we have for alternative medicine is just not there yet.
Also, it’s imperative for our patients to recognize that alternative medicine is not without risks. The guidelines contain a section in which we discuss not only the potential benefits, but the risks associated with using these alternative therapies. This is very important to take into consideration as patients may often be unaware of some of the risks of alternative medicine because they perceive them to be “natural.” However, one should always be aware of the potential risks, especially of anything that is taken in larger quantities.
In addition, we reviewed the role of diet as well as different supplements for psoriasis management. At the current time, the conversation around omega-3 oil remains controversial. There is evidence both for and against its use, meaning that the evidence does not support its beneficial effects in psoriasis. Evaluating the data here can be difficult because a lot of studies use different doses and different types of omega-3 oil that is refined in different ways, so we currently do not support the use of omega-3 oil as a monotherapy for psoriasis. Again, if patients want to add it on to their regular medical therapy for psoriasis to see if they may benefit, they can, but there are concerns about mercury toxicity and other risks depending on the way in which the fish oil is extracted.
Oral vitamin D supplementation is also quite interesting. We know topical vitamin D supplementation, when formulated in the right fashion, is effective in treating psoriasis. However, the doses of oral vitamin D supplementation that were studied for psoriasis have not uniformly shown a significant benefit. Therefore, we again would not recommend oral vitamin D as a full treatment for psoriasis. Certainly, there are other health benefits to vitamin D supplementation, but when we’re looking at oral vitamin D for the treatment of psoriasis, we should inform our patients that the expectations should be a little bit muted.
The last thing that I’ll highlight is the gluten-free diet because we get a lot of questions about this one from our patients. Based on our current understanding, the evidence does not support the independent significant benefit of a gluten-free diet for patients with psoriasis who have no history of celiac disease. However, if a patient has psoriasis as well as confirmed celiac disease, a gluten-free diet would be helpful. In those patients — who are actually few and far between — there is likely a much stronger connection between psoriasis and a gluten-free diet than in the majority of patients for whom that particular connection might be a bit more tenuous.
Healio: How do the guidelines recommend that physicians assess disease severity?
Armstrong: For psoriasis disease severity, we highlighted several different instruments in the guidelines, but we emphasize that there are three kinds of elements of defining psoriasis: what it looks like on the skin, which we as clinicians can observe; the symptoms, such as itching, burning and stinging; and how psoriasis impacts quality of life, including the effects on a patient’s work or personal relationships. It is important to take all three of those components into consideration.
So, when we’re looking for signs of psoriasis, body surface area (BSA) is still one of the most useful measures for disease severity. Now, obviously, it is not all-encompassing and has its limitations, but it is very easy to use. When we think about 1% of BSA essentially being the area of the patient’s handprint, it is easier to explain to our patients and easy to assess in the clinic. Therefore, the guidelines reiterate the utility of BSA in the clinical context. In addition to that, we have the Physician Global Assessment where we rank the disease severity from clear to severe using a five-point scale, which is also easy to use and is helpful in terms of clinical utility.
There are other measures, including the Psoriasis Area and Severity Index (PASI), which is used ubiquitously in clinical trials. However, although it’s very sensitive and responsive to change, it is not that easy to do clinically. Therefore, in the guidelines, we recognize that the utility of instruments such as PASI is most evident in clinical trial settings and perhaps less so in clinical settings unless a clinician is asked to use it to access to a medication, for example.
Healio: Did the guideline authors identify areas that necessitate further research?
Armstrong: Yes. We determined that we will need more evidence in all three areas that we discussed.
In terms of FDA-approved topical therapies, the focus will be on non-steroidal topical agents that can be helpful in treating our patients with psoriasis. Additionally, the long-term use of topical agents is an area of interest as well.
Regarding alternative medicine, it’s still a little bit of a ‘Wild West.’ We would love to have more research into the various agents out there to understand more precisely their efficacy and safety profiles so that we can inform our patients appropriately.
Finally, in the area of psoriasis disease severity measurements, our field has come a long way in understanding disease burden and how to measure it. For example, last year, the International Psoriasis Council put out an article looking at psoriasis disease severity based on two categories: patients who are candidates for topical therapies and patients who are candidates for systemic therapy. So, there are a number of different movements trying to address some of our gaps in knowledge and more comprehensively capture the disease burden experienced by our psoriasis patients.
Reference:
Elmets CA, et al. J Am Acad Dermatol. 2020;doi:10.1016/j.jaad.2020.07.087.
For more information:
To follow April W. Armstrong, MD, on social media, follow @aprilarmstrongmd on Instagram or subscribe to her YouTube channel.
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