By Lauren Johnston
Over the past 20 years, dermatologist James Krell, MD has seen dramatic improvements in treatments for psoriasis patients.
“It’s very encouraging,” he said. “When I started treating patients with psoriasis in the early 1990s, I did lots of phototherapy and widespread, relatively unsafe, immunosuppressive therapy. Now we’re putting patients on very safe biologic drugs that get them completely clear.”
Psoriasis is a chronic inflammatory skin disease that causes red, itchy plaques in certain areas of the body, commonly the scalp, elbows, knees, and buttocks. The most common type is plaque psoriasis. The less common types include guttate psoriasis, pustular psoriasis, and erythrodermic psoriasis. On average, patients typically see the first signs of this skin disease when they are in their mid to late 20s. Researchers are still studying the causes of this disease and working to identify the genes that effect it.
“About 30 percent of psoriasis patients inherit it from a family member, but that means that it just occurs in about 70 percent of the cases, which we call de novo (on its own). We’re not sure why someone might get psoriasis in the absence of family history. One exception is the second most common form, guttate psoriasis,” Krell said. This form, which is also called dew drop psoriasis, is usually caused by an underlying strep infection. It leaves red, teardrop-shaped spots on the skin like sprinkled dew drops.
While there is no cure for psoriasis, new research and medications within the last 20 years have greatly improved the treatment physicians can offer. Krell conducts psoriasis clinical trials and receives referrals from across the state for patients with challenging and rare cases.
“In the late 80s, no one thought psoriasis was based on the immune system,” Krell said. “Then there was a patient who got a transplant and was put on immunosuppressive therapy to protect them from rejecting the donated organ. This patient had psoriasis, and all their psoriasis disappeared. From that point on, people recognized that this is an immune-based disease. Then researchers tried to identify the immune-based causes, but they weren’t able to find any answers.”
In the 1980s and 1990s, physicians treated psoriasis with a broad variety of therapies, but the most common was phototherapy, which is ultraviolet light therapy. Patients would receive this treatment two or three times a week to clear up their skin. Other immunosuppressive therapies were commonly used, but had side effects.
In the early 2000s, researchers discovered that overproduction of certain protein cells was a leading cause for psoriasis. Pharmaceutical companies then began to identify medication that would target these protein cells that are overwhelming the body.
“In the last two decades, we’ve gotten new biologic therapies that mimic the biologic process in the body, but try to block those overproduced proteins,” Krell said.
These proteins are produced by cells like the T helper 17 (Th17) and interleukin-23 (IL-23), which are key drivers of psoriasis. Blocking the production of these cells dramatically slows down the disease. With these new biological therapy options, Krell can help most patients obtain completely clear skin.
“I have seen many patients go from widespread psoriasis with a miserable lifestyle to 100 percent clear with a new look on life,” Krell said. “The most recent drug that was approved for psoriasis has shown that somewhere around 70 percent of patients are completely clear after one year. That is remarkable.”
Today, there are about 11 different biologic therapies made by a variety of companies that are approved to treat this disease. Because biological medications are very large proteins, the medicine is usually injected as a shot, but there are two therapies on the market that can be taken orally. The injection form is self-administered at home and can be given as frequently as once a week or as infrequently as once every three months.
Krell has seen improvements in treatments for some of the rarer types of psoriasis, including generalized pustular psoriasis, where a patient develops waves of painful plaques studded with pustules. There is also ongoing research for better topical medications, and every few years an improved type enters the market for physicians to prescribe.
“I’m very hopeful to be able to say to a patient every single day, ‘Don’t worry, I will get your psoriasis 100% clear or close to it.’ I was never able to say that 20 years ago, even 10 years ago, but now I say it to almost every new patient that walks in the door,” Krell said.
In the future of psoriasis treatment, Krell predicts more affordable treatments, more oral biologic medications, more patients treated in the earlier stages, and less untreated psoriasis. He’s also hopeful that there will be fewer associated comorbidities, like depression.
