Lynch M, Malara A, Timoney I, et al. - In this 39-week, single-centre, randomised controlled trial, researchers sought to compare the impacts of sitagliptin treatment, a DPP-4 inhibitor, in combination with narrow-band ultraviolet-B (NB-UVB) phototherapy compared to NB-UVB alone on psoriasis severity, quality of life, cardiovascular disease risk factors and immune parameters in people with moderate psoriasis without type 2 diabetes mellitus (T2DM). People were allocated randomly to obtain sitagliptin for 24 weeks with NB-UVB or NB-UVB alone. In total, 118 patients were randomised. In patients with moderate psoriasis without T2DM, sitagliptin therapy combined with NB-UVB phototherapy significantly improved psoriasis severity, albeit modestly, compared to NB-UVB phototherapy alone. There were no serious adverse events associated with the treatment.