A clinical trial of a psoriasis treatment by partners Astrazeneca and Amgen met its primary endpoints, the pharmaceutical companies announced on Wednesday.AMAGINE-1, a pivotal, multi-arm Phase III trial evaluating two doses of brodalumab in over 1,800 patients with moderate-to-severe plaque psoriasis, achieved its targets when compared with both Stelara (psoriasis treatment also known as ustekinumab) and placebo by week 12.A dose of 210mg of brodalumab given every two weeks was shown to be superior to Stelara on the primary endpoint of clearing the skin disease."AMAGINE-2 is the third and final pivotal study in our Phase III psoriasis programme and the robust data from these studies will form the basis of our global filing plan," said Amgen's executive vice president of research and development, Sean Harper."We look forward to discussions with regulatory authorities," he said.Astrazeneca's shares were trading broadly flat following the news at 4,674p by 08:44.