The successful management of SJS/TEN secondary to enfortumab vedotin therapy

A 47-year-old female with poorly differentiated carcinoma of urothelial origin on pembrolizumab, presented to the hospital with fever, dysuria, pruritus, diffuse erythema, and skin desquamation 11 days after starting immunotherapy with enfortumab vedotin (EV). The desquamation covered about 25% of her body surface area and she subsequently developed a positive Nikolsky sign, bullae, and oral erosions. Labs were significant for elevated LFTs: 121 u/L (AST), 129 u/L (ALT), 147 u/L (ALP), CBC, and BMP were within normal limits.Histopathology demonstrated a vacuolar interface dermatitis consistent with an adverse drug reaction.EV was immediately stopped, and two doses of Etanercept 50 mg were administered subcutaneously followed by a three-day course of 200 mg IVIG, resulting in dramatic improvement of her rash. The patient required an ICU stay for worsening respiratory status and was discharged after five days of admission.According to a phase II trial, 48% of individuals receiving EV therapy developed treatment-related rashes. Post-marketing analysis data presented eight cases of serious skin reactions defined as either Stevens-Johnson Syndrome (SJS) or Toxic Epidermal Necrolysis (TEN) after EV therapy. The majority of reports are from singular cases or case series. Further research is necessary to establish the real-world incidence of SJS/TEN in post market analysis from EV and management of the same.