Enbrel first biologic with up to 9 years rheumatoid arthritis safety, sustained efficacy data

THOUSAND OAKS, Calif., November 12, 2006 -- Amgen (NASDAQ: AMGN) today announced that Enbrel? (etanercept) is the first biologic with published data to show improvements in multiple measures of efficacy that were sustained in rheumatoid arthritis (RA) patients completing up to nine years of therapy. These new data are being presented at the American College of Rheumatology (ACR) Scientific Meeting in Washington, D.C.

"The current data in Rheumatoid Arthritis suggest that Enbrel is both effective and safe in long-term use," said Mark Genovese, M.D., Stanford University Medical Center, Palo Alto, California. "These findings are significant because they provide a degree of reassurance to both the patient and the physician that unexpected safety concerns do not appear to be developing after nine years of use."

ENBREL continues to have a strong safety profile for extended periods of use. In the studies presented at ACR, rates of serious adverse events and serious infections remained low and were consistent with controlled portions from the double-blind phases of the studies. The overall number of observed malignancies (excluding nonmelanoma skin cancers) were similar in type and number to what would be expected in the general population.

Additionally, data showed that 77 early rheumatoid arthritis (ERA) and 280 long-standing rheumatoid arthritis (LRA) patients who completed ENBREL treatment for up to eight years experienced substantial improvements in their ACR scores. Additionally, 73 LRA patients who completed ENBREL treatment for up to nine years experienced similar improvements. ACR scores are a composite measure of improvement in RA symptoms, including joint swelling and tenderness, pain, level of disability, overall patient and physician assessment, and an objective marker of inflammation, such as erythrocyte sedimentation rate.

Data being presented at ACR showed that ENBREL provided sustained improvement in the signs and symptoms of RA, in those patients who continued in the study, regardless of duration of disease. Following eight years of ENBREL therapy: 75 percent of ERA patients and 76 percent of LRA patients achieved ACR 20; 60 percent of ERA patients and 52 percent of LRA patients achieved ACR 50; 35 percent of ERA patients and 26 percent of LRA patients achieved ACR 70. Further, for those patients with LRA who received ENBREL treatment for nine years, 74 percent achieved ACR 20, 41 percent achieved ACR 50, and 22 percent achieved ACR 70.

The ability to perform daily activities is an important goal for many people with RA, and data presented at ACR showed that treatment with ENBREL may help them achieve this goal. Through eight years of treatment with ENBREL, data showed that 73 to 85 percent of patients with ERA and 53 to 72 percent of patients with LRA achieved a clinically significant improvement in the Health Assessment Questionnaire (HAQ) score, a patient questionnaire that measures disability. A clinically significant improvement in HAQ was defined as at least a 0.22 improvement from baseline.

"Before I was diagnosed with RA, the pain, stiffness and fatigue stopped me from doing many of the activities I enjoyed," said Gloria Treece, a participant in the study. "Since starting ENBREL treatment approximately nine years ago, I'm now able to take part in many activities with my family."

These studies were designed to assess the safety and long-term efficacy of ENBREL in adult LRA patients who have failed to respond to at least one disease-modifying antirheumatic drug, and adult patients with ERA (defined as less than or equal to three years of disease duration). Patients with RA who participated in controlled clinical trials of ENBREL were eligible to enroll in open-label extension studies (LRA, N=644; ERA, N=207).