THOUSAND OAKS, Calif., March 28, 2012 /PRNewswire/ -- Amgen (NASDAQ:AMGN) announced today that results from a Phase 2 trial evaluating the safety and efficacy of brodalumab (formerly AMG 827) in 198 patients with moderate to severe plaque psoriasis were published in the New England Journal of Medicine. The 12-week, dose-ranging study achieved its primary endpoint with the mean percentage improvement in psoriasis area and severity index (PASI) score higher in all brodalumab groups compared to placebo ( p<0.001). Brodalumab is a human monoclonal antibody that selectively binds to and blocks signaling via the interleukin-17 (IL-17) receptor, thereby stopping the binding of several IL-17 family members associated with psoriasis. The majority of subjects treated with brodalumab 210 mg every other week achieved total clearance of their skin disease (PASI 100 of 62 percent). PASI score is a measure of psoriatic plaque redness, scaling and thickness and the extent of involvement in each region of the body. Treatment efficacy is often measured by the reduction of PASI from baseline (i.e., a 75 percent reduction is known as PASI 75, a 90 percent reduction is known as PASI 90 and a PASI 100 is total clearance of skin disease). "There are a variety of treatment options available to those living with psoriasis, yet these options are unable to help many patients achieve their therapeutic goals," explained Kim Papp, M.D., Ph.D., the study's lead author and director at Probity Medical Research, Ontario, Canada. "In this Phase 2 study, brodalumab showed a high level of response in patients with moderate to severe plaque psoriasis with a rapid onset of action within days. Based on these results, additional clinical trials are warranted to further assess the safety and efficacy of brodalumab." Psoriasis affects approximately 125 million people worldwide and is a chronic disease of the immune system that causes the skin cells to grow at an accelerated rate. Although there are several types of psoriasis, approximately 80 percent of patients have plaque psoriasis, which can cause painful and itchy red, scaly patches to appear on the skin.