Improvement of Low-Dose Abrocitinib-Resistant Lichen Amyloidosis with Dupilumab: Two Case Reports.

Lichen amyloidosis (LA), a form of primary localized cutaneous amyloidosis, is often refractory to conventional therapies. We report two LA patients who showed inadequate response to 100mg abrocitinib daily but achieved significant improvement with dupilumab. A 29-year-old woman and a 31-year-old man with chronic, pruritic LA lesions experienced rapid itch relief with abrocitinib but minimal skin improvement after 4-6 months, along with adverse effects, such as diarrhea, acneiform eruptions, and herpes simplex reactivation. After switching to dupilumab, both patients maintained pruritus control and exhibited marked lesion regression, with no side effects. While abrocitinib effectively alleviated itch, dupilumab demonstrated superior lesion resolution, possibly due to its dual inhibition of IL-4 and IL-13 signaling, which may more comprehensively address the underlying inflammation in LA. This is the first report of dupilumab's efficacy after low dose abrocitinib failure in LA, suggesting its potential as a therapeutic option for refractory cases. Further studies are needed to confirm these findings.