Dupilumab for the treatment of pemphigoid gestationis in the setting of breastfeeding: a case report and review of the literature.

Pemphigoid gestationis (PG) is a rare blistering dermatosis usually seen in the second and third trimesters of pregnancy. Treatment of PG is aimed towards the relief of pruritus and prevention of new lesions from developing, often involving high-potency topical corticosteroids, antihistamines, oral corticosteroids and other systemic immune modulators for patients with symptoms of greater severity. Recently, dupilumab, a monoclonal antibody against the alpha subunit of the interleukin-4 receptor, has been used successfully in bullous pemphigoid. We discuss the case of a 34-year-old Asian woman at 32 weeks' gestation who presented with progressive and severely pruritic oedematous urticarial plaques and patches dispersed across the trunk and extremities, with scattered tense bullae. A skin biopsy confirmed the diagnosis of PG. The patient was placed on high-dose oral corticosteroids and concomitant topical steroids, with minimal resolution after attempts to taper oral steroids over the next 4 weeks. Oral prednisone was continued at 17.5 mg for the remainder of her pregnancy given the risks associated with higher dosages. After delivery, the patient's disease worsened, requiring an increase in prednisone. Given that the patient was breastfeeding, dupilumab was initiated as a steroid-sparing agent allowing patient to be tapered off prednisone with significant improvement and control of her disease. The safety of dupilumab for infants who are being breastfed remains under discussion. Herein, we discuss the existing literature and considerations regarding pregnancy and breastfeeding for patients with PG on dupilumab.