the choice of therapeutic agents for patients with moderate to severe psoriasis has expanded significantly in the past decade with new understanding of the immunologic basis of psoriasis multiple new potential targets for therapy have been identified it is likely that a series of new medications to focus on the newly identified pathways is on the horizon the first pathway targeted by new medications focuses on the p40 subunit that is shared by interleukin il 12 and il 23 two human anti p40 antibodies have been used therapeutically in psoriasis to date ustekinumab cnto 1275 stelara centocor horsham pa and briakinumab abt 874 abbott abbott park il ustekinumab was recently approved by the united states food and drug administration making it the first medication approved in the united states to work by this pathway while briakinumab is currently in phase iii clinical trials.