Dupilumab enables glucocorticoid withdrawal in refractory multisite mucous membrane pemphigoid: a case report.

Background: Mucous membrane pemphigoid (MMP) is a mucosal-predominant, potentially scarring autoimmune subepithelial blistering disease. Although dupilumab is approved for adult bullous pemphigoid, its use in MMP remains off-label and published experience is limited. Case presentation: We report a 77-year-old man with refractory mucous membrane pemphigoid presenting with recurrent painful oral erosions, ocular symptoms, suspected nasopharyngeal/upper-airway involvement, and widespread cutaneous blisters. Histopathology showed a subepidermal blister, and direct immunofluorescence revealed linear C3 and IgG deposition along the basement membrane zone; BP180 and BP230 antibodies were elevated. Despite long-term systemic glucocorticoids, disease activity persisted, with chronic obstructive pulmonary disease, prior prostate cancer, and 7.5-kg acute weight loss. Dupilumab was initiated with scheduled prednisone tapering. Pruritus and new blister formation rapidly decreased, erosions re-epithelialized, and oral symptoms, ocular dryness, and tearing improved, prednisone was discontinued after 3 months, and dupilumab monotherapy maintained remission without serious adverse events. Conclusion: This case highlights dupilumab-mediated IL-4/IL-13 blockade as a potential steroid-sparing strategy for carefully selected patients with refractory multisite MMP in whom conventional broad immunosuppression carries substantial risk, while emphasizing that control of active inflammation may not reverse established cicatricial damage and that longer-term controlled studies are needed to confirm its efficacy, durability, and safety.