IL17A and psoriasis: Moreover, the t1/2 of caplacizumab, a NANOBODY® VHH without an HSA-binding domain, is 38.5 h in humans after subcutaneous administration [22], while an anti-IL-17 NANOBODY® VHH compound with HSA-binding domains has a t1/2 of 11–12 days following subcutaneous administration in patients with psoriasis [23] and the t1/2 of OZR, which possesses an HSA-binding domain, is 18 days.