Delayed-type Hypersensitivity to Secukinumab with Tolerance to Ixekizumab

The IL-17 inhibitors secukinumab, ixekizumab, and brodalumab are used to treat psoriatic arthritis (PsA) when patients fail to respond to TNF-α inhibitors, and they are currently preferred over IL-12/23-inhibitors.1 Secukinumab, an IL-17A inhibitor, exhibits a good safety profile, with mainly mild upper respiratory tract infections and candidiasis being highlighted. Here, we report a patient with a severe injection-site reaction to secukinumab, manifesting as a cutaneous delayed-type hypersensitivity (DTH), and we detail the allergy workup.