WASHINGTON — , Shawn G. Kwatra, MD, said at the ElderDerm conference on dermatology in older patients hosted by the GW School of Medicine & Health Sciences.
“We found a few years ago that eosinophils seem to differentiate this group, and now we’re finding that IgE and CBC [complete blood count] differential can help you get a little better sense of who has an immune-driven itch vs something more neuropathic,” said Dr. Kwatra, professor and chair of dermatology at the University of Maryland, Baltimore, who founded and directed the Johns Hopkins Itch Center before coming to the University of Maryland in 2023. Not all patients with immune-driven itch will have these biomarkers, “but it’s a helpful tool,” he said.
Dr. Kwatra
Dr. Shawn G. Kwatra
CPUO is the term that is increasingly being used, he said, to describe intense, chronic pruritus without primary skin lesions or rashes and without any known systemic cause. It becomes more common as people get older and is sometimes debilitating. The initial evaluation should be kept “simple and straightforward,” he advised, with heightened concern for underlying malignancy in those who present with an itch of less than 12 months’ duration.
Biologics, JAK Inhibitors: Case Reports, Ongoing Research
Research conducted by Dr. Kwatra and Jaya Manjunath, a fourth-year medical student at The George Washington University, Washington, documented higher levels of Th2-associated cytokines and inflammatory markers in patients with CPUO who had elevated IgE or eosinophil levels, or both than in patients with itch who had low IgE and eosinophil levels. The patients with higher levels also had a greater response to off-label treatment with immunomodulatory therapy.
“Multiple Th2-related inflammatory markers, like IL [interleukin]-5 and eotaxin-3, were reduced after dupilumab” in patients who responded to the therapy, said Ms. Manjunath, who co-presented the meeting session on chronic itch with Dr. Kwatra. Other changes in the plasma cytokine profile included a reduction in the serum level of thymus and activation-regulated chemokine, which is a biomarker for atopic dermatitis. The research is under review for publication.
Meanwhile, a phase 3 trial (LIBERTY-CPUO-CHIC) of dupilumab for CPUO is currently underway, Dr. Kwatra noted. Investigators are randomizing patients with severe pruritus (Worst Itch Numeric Rating Scale [WI-NRS] ≥ 7) to dupilumab or placebo for 12 or 24 weeks.
In one of several cases shared by Dr. Kwatra and Ms. Manjunath, a 71-year-old Black woman with a 6-month history of generalized itch (WI-NRS = 10) and a history of type 2 diabetes, hypertension, and chronic kidney disease was found to have elevated eosinophil levels and a negative malignancy workup. Previous therapies included antihistamines and topical steroids. She was started on a 600-mg loading dose of subcutaneous dupilumab followed by 300 mg every 14 days. At the 2-month follow-up, her WI-NRS score was 0.
Because “dupilumab is off label right now for this form of itch, oftentimes our first line is methotrexate,” Dr. Kwatra said. Patients “can have a good response with this therapeutic.”
He also described the case of a 72-year-old Black woman with total body itch for 2 years (WI-NRS = 10) and a history of seasonal allergies, thyroid disease, and hypertension. Previous therapies included prednisone, antihistamines, topical steroids, and gabapentin. The patient was found to have high IgE (447 kU/L) and eosinophil levels (4.9%), was started on methotrexate, and had an itch score of 0 at the 8-month follow-up.
JAK inhibitors may also have a role in the management of CPUO. A phase 2 nonrandomized controlled trial of abrocitinib for adults with prurigo nodularis (PN) or CPUO, recently published in JAMA Dermatology, showed itch scores decreased by 53.7% in the CPUO group (and 78.3% in the PN group) after 12 weeks of treatment with oral abrocitinib 200 mg daily. Patients had significant improvements in quality of life and no serious adverse events, said Dr. Kwatra, the lead author of the paper.
One of these patients was a 73-year-old White man who had experienced total body itch for 1.5 years (predominantly affecting his upper extremities; WI-NRS = 10) and a history of ascending aortic aneurysm, hypertension, and hyperlipidemia. Previous failed therapies included dupilumab (> 6 months), topical steroids, tacrolimus, and antihistamines. Labs showed elevated IgE (456 kU/L) and eosinophil levels (11.7%). After 12 weeks of treatment with abrocitinib, the WI-NRS decreased to 2.