Psoriasis is associated with atherosclerosis, in which circulating microparticles play an important role. In severe psoriasis, there was an increase of endothelial- and platelet- microparticles which could be decreased by anti-TNFα. However, whether anti-IL-12/23 treatment would decrease the level of microparticles remains unknown. Our study showed that, despite the clinical improvement of psoriasis after IL-12/13 blockage, the increased levels of circulating CD41a and CD31 microparticles were unchanged after anti-IL-12/23. This result suggested that anti-IL12/23 treatment may not alter the development of cardiovascular disease in patients with psoriasis.