Rare, Severe Type of Psoriasis Merits Biologic Consideration, Researchers Say

New biologics should be considered for cases of generalized pustular psoriasis (GPP), a rare, potentially life-threatening inflammatory skin disease, according to German researchers.

The retrospective analysis sought to assess patient and disease characteristics and analyze drug survival rates in the treatment of GPP in a real-life setting, in this instance, from dermatology centers located in 5 university medical centers in Germany. In the landscape of biologics, drug survival is another way of referring to drug retention or drug persistence.

GPP is a chronic-relapsing and potentially life-threatening disorder and is considered a phenotype of pustular psoriasis. It presents with multiple coalescing sterile pustules on erythematous skin; patients may also have fever, malaise, high white blood cell counts, and elevated C-reactive protein (CRP). It can also appear as arthritis, acute respiratory distress syndrome, cholestasis, and neutrophilic cholangitis. Because it is so rare, data from larger, high-quality clinical studies are not available, the authors wrote.

Researchers analyzed medical records from January 2005 to May 2019 containing information about 201 treatment series from 86 patients with GPP. Those who had exclusive treatment with systemic glucocorticoids or phototherapy were excluded, as were patients with 1 prior course of treatment with anakinra but who then switched to secukinumab; or with brodalumab who then switched to ustekinumab.

Overall, 65.1% of the patients were female, with an average age of 51.2 years when GPP began; they had a mean disease duration of 8.7 years. Laboratory results from their first visit to a medical center showed elevated CRP in just over 75% of the patients; 62.4% had leukocytosis; 38.1% had an electrolyte imbalance; other patients had hypocalcemia, hypo- or hyperkalemia, or hyponatremia.

Additional characteristics stemming from flare-related complications that indicated the severity of the disease included:

• Infections in 36.2% of patients
• Acute renal failure in 11.3%
• Septicemia in 6.7%
• Heart failure in 5.1%

Additionally, nearly 13% of the patients needed admission to an intensive care unit or other intensive care due to a GPP flare; 74.1% of patients had evidence of disease at the time of their last visit.

Patients had received an average 2.3 systemic therapies for GPP. Psoriatic vulgaris was diagnosed in 50.0% and psoriatic arthritis in 17.4% of the patients.

Overall, an excellent response was reached in 41.3% of all treatment courses, and a partial response was seen in 31.4%. Nonresponse occurred in 27.3% of treatment courses.

Biological treatment was significantly more effective than nonbiological therapies, with biologics seeing an excellent response in 47.4% of treatment series compared with 35.9% of nonbiologics (P = .02). Overall, the median drug survival was 14 months (36 months for biologics vs 6 months for nonbiologics; P <.001).

Inhibitors of interleukins 17A and 23 showed particularly strong efficacy and drug survival, the researchers said, and should be considered earlier in the course of the disease. They noted that in Japan, guidelines on GPP recommend biologics and anti–tumor necrosis factor agents for GPP; in Germany, corticosteroids and acitretin are the only licensed drugs for GPP.

The crude probability of drug survival was highest for secukinumab (HR of drug discontinuation compared with acitretin, 0.22), followed by ixekizumab and ustekinumab (HR, 0.38 each).

“This study is one of the larger case series adding to the growing evidence on treatment of GPP and, to our knowledge, is the first in-depth analysis of drug survival in GPP in a real-life setting,” the researchers wrote.

Reference

Kromer C, Loewe E, Schaarschmidt ML, et al. Drug survival in the treatment of generalized pustular psoriasis: a retrospective multicenter study. Dermatol Ther. Published online January 26, 2021. doi:10.1111/dth.14814