A Rare Case of Dupilumab Monotherapy in Pemphigoid Nodularis and a Comprehensive Literature Review

Pemphigoid nodularis (PN) is a rare, refractory variant of bullous pemphigoid (BP) characterized by prurigo nodularis-like lesions and the immunopathologic features of BP. Its management is challenging, especially in elderly patients for whom conventional immunosuppressants pose significant risks. Dupilumab, a monoclonal antibody inhibiting IL-4 and IL-13 signaling, has emerged as a promising therapy for BP, but its efficacy in PN is not well-established. A 71-year-old female patient presented with a 10-day history of intensely pruritic, tense blisters and nodules on her hands, feet, and trunk. Histopathology confirmed acanthosis and hyperkeratosis of epidermis, also subepidermal blister with eosinophils, and direct immunofluorescence revealed linear IgG and C3 deposition at the basement membrane zone, diagnosing PN. Due to her age and contraindications for long-term steroids, she was started on dupilumab monotherapy (600 mg loading dose, then 300 mg every two weeks). The patient experienced rapid pruritus relief within 72 hours and significant lesion healing by week 4, with no adverse events. This case demonstrates that dupilumab monotherapy is a highly effective and well-tolerated treatment for PN. It provides rapid, steroid-free disease control, supporting its use as a first-line biologic agent for this debilitating condition. This report is bolstered by a growing body of evidence from real-world studies on dupilumab in BP.