THOUSAND OAKS, Calif. and LONDON, June 11, 2014 /PRNewswire/ -- Amgen (NASDAQ:AMGN) and AstraZeneca today announced that results from a Phase 2 study evaluating brodalumab in 168 patients with psoriatic arthritis were published in The New England Journal of Medicine (NEJM). These data will also be presented at the 2014 European League Against Rheumatism (EULAR) Annual Congress in Paris on June 14, 2014 ( 10:15 a.m. CEST, Abstract No. SAT0404). Brodalumab is the only investigational treatment in development that binds to the interleukin-17 (IL-17) receptor and inhibits inflammatory signaling by blocking the binding of several IL-17 ligands to the receptor. The IL-17 pathway plays a central role in inducing and promoting inflammatory disease processes. The study showed that treatment with brodalumab significantly improved signs and clinical symptoms associated with the disease, including tender and swollen joints, at 12 weeks as measured by a 20 percent improvement in the American College of Rheumatology response criteria (ACR20). The study also showed that many patients continued to improve, and that the improvements were sustained, through the first 52 weeks of the study reported in NEJM. "Given our understanding of the role of the IL-17 receptor, we have developed a robust clinical program for brodalumab across the spectrum of inflammatory disease, including psoriasis, psoriatic arthritis and asthma," said Sean E. Harper, M.D., executive vice president of Research and Development at Amgen. "These encouraging psoriatic arthritis data showing that patients not only experienced improvements in clinical symptoms at week 12, but that those improvements continued over time and were sustained, were the basis for our decision to continue development of this molecule as a potential treatment for the many people who are looking to better control their disease." The study achieved its primary endpoint with both doses of brodalumab exhibiting superiority to placebo in ACR20 responses at week 12. These responses continued to improve through 24 weeks and were sustained through the first 52 weeks of the study. 1 ACR response criteria are a measure of improvement in tender and swollen joints, as well as patient and physician global assessments of disease activity, pain, disability and inflammatory markers. A 20 percent improvement from baseline in ACR response rates is known as ACR20, a 50 percent improvement from baseline is known as ACR50 and a 70 percent improvement from baseline is known as ACR70. "We're encouraged that treatment with brodalumab significantly reduced clinical signs and joint symptoms, compared to placebo, and that similar degrees of disease improvement were seen in biologic-treated and biologic-naive patients with psoriatic arthritis," stated Philip Mease, M.D., lead investigator and study author, Swedish Medical Center and University of Washington. "These results add to the growing body of evidence indicating that the IL-17 receptor is a promising target for the treatment of inflammatory diseases, including psoriatic arthritis." Overall, adverse events were similar across groups with 3 percent of brodalumab-treated patients experiencing serious adverse events versus 2 percent of placebo recipients (four patients in total). Serious adverse events included skin infection (cellulitis, two cases), abdominal pain and inflammation of the gallbladder (cholecystitis). No clinically significant neutropenia ( >Grade 2) was reported in this study. "There is a significant need for new treatment options for people living with psoriatic arthritis for whom currently available treatments do not work. As an antibody targeting the IL-17 receptor, brodalumab is designed to work differently from existing treatment options," said Briggs W. Morrison, M.D., executive vice president of Global Medicines Development at AstraZeneca. "We are encouraged by the efficacy and safety profile demonstrated in this study and are investigating the potential of brodalumab in Phase 3 trials for psoriatic arthritis." Amgen and AstraZeneca have initiated two Phase 3 studies of brodalumab in psoriatic arthritis, AMVISION-1 and AMVISION-2, which together will provide detailed information on the impact of brodalumab on improving clinical signs and symptoms in psoriatic arthritis, as well as its ability to prevent joint damage.