TUESDAY, June 25, 2024 (HealthDay News) -- For patients with prurigo nodularis (PN) and chronic pruritus of unknown origin (CPUO), abrocitinib, a Janus kinase 1 inhibitor, is effective and well tolerated, according to a study published online June 5 in JAMA Dermatology.

Shawn G. Kwatra, M.D., from the University of Maryland School of Medicine in Baltimore, and colleagues examined the efficacy and safety of 200-mg oral abrocitinib administered once daily in a phase 2, nonrandomized controlled trial involving 20 adult patients with moderate-to-severe PN or CPUO (10 with each). All 20 patients completed the 12-week treatment period, and 18 completed the four-week follow-up.

The researchers found that the Peak Pruritus Numerical Rating Scale (PP-NRS) scores decreased by 78.3 and 53.7 percent in PN and CPUO patients, respectively, by week 12. Eight of 10 patients with PN and six of 10 with CPUO achieved at least a 4-point improvement on the PP-NRS from baseline to week 12. Significant improvement in quality of life was experienced by both groups, as demonstrated by percentage change in Dermatology Life Quality Index scores (−53.2 and −49.0 percent for PN and CPUO, respectively). Acneiform eruption was the most common adverse event among patients (10 percent); there were no serious adverse events reported.

"Larger randomized, double-blind, placebo-controlled trials are needed to validate these findings, identify less common adverse effects, allow for subgroup analyses, and identify differences in systemic inflammatory markers between patients who respond to treatment and those who do not," the authors write.

One author disclosed ties to pharmaceutical companies, including Pfizer, which funded the trial and made and supplied the study drug.

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