Biologic therapies for the treatment of moderate‐severe plaque psoriasis include tumour necrosis factor‐α inhibitors (TNFi), such as infliximab, etanercept and adalimumab; an inhibitor of the p40 subunit common to interleukin (IL)12 and IL23, ustekinumab; and inhibitors of IL‐17A, secukinumab and ixekizumab. Here, IL17A is linked to psoriasis vulgaris.