A Phase 3 Trial to Look at the Safety and Effectiveness of Ustekinumab in Korean and Taiwanese Subjects With Moderate to Severe Plaque-type Psoriasis

This is phase 3, multicenter, randomized, placebo-controlled double-blind, parallel study of subcutaneous injection of placebo and ustekinumab 45mg in Taiwanese and Korean patients with moderate to severe plaque psoriasis. Ustekinumab is an experimental medicine that is being tested to see if it may be useful in treating moderate to severe psoriasis. The patients will receive either ustekinumab or placebo at week 0 or week 4, and will be followed up through week 36. Patients who randomized (study drug assigned by chance) to placebo will cross over to ustekinumab 45mg group at week 12 and week 16 .The effectiveness of ustekinumab will be compared with placebo treated patients at week 12. Safety information will be collected through week 36. Patients randomized to ustekinumab will receive placebo at week 12 to maintain the blind and additional dose of 45mg at week 16. This study will be conducted in approximately 13 sites in South Korea and Taiwan and will include approximately 120 patients with approximately 60 patients in each country. This study is "blinded." This means that neither you nor your study doctor will know in which group you are placed. However, in case of medical emergency, your study doctor can quickly find out which treatment group you are in. You may get either ustekinumab or placebo (which looks like the medicine being studied but has no active ingredients) at the start of the study. All patients in the study will eventually receive Ustekinumab after week 12. Patients assigned to the ustekinumab will receive 45 mg subcutaneously at weeks 0, 4 and 16; and placebo at week 12. Patiens assigned to placebo will receive subcutaneous injections of placebo at weeks 0 and 4; then crossover to 45 mg of ustekinumab at weeks 12 and 16. Duration of study participation up to 36 weeks.