Denosumab Achieved Superior Bone Mineral Density Gains in Head-to-Head Trial versus Weekly Alendronate (FOSAMAX(R))

Amgen (NASDAQ: AMGN) today announced complete results from a head-to-head, double-blind study comparing the effects of twice-yearly subcutaneous injections of denosumab versus weekly oral doses of alendronate (FOSAMAX®) on bone mineral density (BMD) in postmenopausal women with low BMD. The results were presented during a late breaking session at this year’s 35th Annual European Symposium on Calcified Tissues (ECTS) meeting. Top-line results of this study were previously reported in January 2008. In the non-pivotal Phase 3 study, administration of denosumab resulted in significantly greater BMD gains at all sites measured, compared with alendronate. "This study is the first of any investigational or approved therapy to show greater BMD gains compared with alendronate at all skeletal sites measured,” said Jacques Brown, lead study investigator, Laval University and Le Centre hospitalier, Universitaire de Québec. "We may be seeing a greater effect with denosumab at all sites measured because as a RANK Ligand inhibitor, denosumab may be able to target all osteoclasts – wherever they are found in bone tissue throughout the skeleton – and at all stages of their formation and function.” For the primary endpoint, denosumab resulted in significant increases in BMD at the total hip compared with alendronate (3.5 percent vs. 2.5 percent, p<0.0001). Denosumab also resulted in significant increases in BMD compared with alendronate at the trochanter (4.5 percent vs. 3.5 percent), 1/3 radius (1.1 percent vs. 0.6 percent), lumbar spine (5.3 percent vs. 4.2 percent), and femoral neck (2.2 percent vs. 1.6 percent) (p=0.0003 at all sites). The company is awaiting results of its pivotal Phase 3 registrational trial later this year that will assess the potential anti-fracture efficacy of denosumab. The incidence and types of adverse events and serious adverse events observed in this study were similar between the denosumab and alendronate treatment groups. The most common adverse events across both treatment arms were arthralgia, back pain, constipation, and dyspepsia. "The results of the head-to-head study presented here at ECTS are encouraging because they demonstrate that administration of denosumab can result in significantly greater BMD gains compared with alendronate,” said Javier San Martin, Global Development Lead for the denosumab osteoporosis program. "The novel means by which denosumab inhibits osteoclast-mediated bone breakdown shows the promise of RANK Ligand inhibition.” Study Design A total of 1,189 women with postmenopausal osteoporosis were randomized 1:1 to receive denosumab or alendronate, and subsequently followed for one year to assess changes in BMD. The study primary endpoint was to evaluate the effect of denosumab on percent change from baseline in BMD at the total hip compared to alendronate. Secondary endpoints were to evaluate the effect of denosumab on percent change from baseline in BMD at the lumbar spine, hip trochanter, femoral neck, and 1/3 radius compared to alendronate. Denosumab: Clinical Studies in Bone Loss and Destruction Denosumab is an investigational fully-human monoclonal antibody in late-stage clinical development that specifically targets RANK Ligand, an essential regulator of osteoclasts (the cells that break down bone). Underscoring Amgen’s commitment to science, its researchers have instituted a broad clinical development program for denosumab as they explore the bone biology of various diseases associated with the RANK Ligand pathway. In addition to four Phase 3 and two Phase 2 trials in postmenopausal osteoporosis, Amgen has evaluated denosumab’s effects on bone erosions in rheumatoid arthritis in a Phase 2 study. In the oncology setting, denosumab is being evaluated in four Phase 3 and two Phase 2 studies in advanced cancer patients with, or at risk for, bone metastases. In a Phase 2 study, denosumab is being evaluated as a possible treatment for patients with multiple myeloma. Osteoporosis: Impact and Prevalence Often referred to as the "silent epidemic,” osteoporosis is a global problem that is increasing in significance as the population of the world both increases and ages. The World Health Organization (WHO) has recently identified osteoporosis as a priority health issue along with other major non-communicable diseases. Although fractures to the vertebrae and hip are the most commonly discussed osteoporotic fractures, they do not account for the majority of fractures. In fact, fractures at skeletal sites such as the wrist, pelvis, humerus, clavicle, femur, and lower leg (tibia/fibula) make up an estimated 59 percent of all osteoporotic fractures in the United States (U.S.).i The economic burden of osteoporosis is comparable to that of other major chronic diseases; for example, in the U.S. the costs associated with osteoporosis-related fractures are equivalent to those of cardiovascular disease and asthmaii,iii,iv. It has been reported that osteoporosis results in more hospital bed-days than stroke, myocardial infarction or breast cancer.v About Amgen Amgen discovers, develops, manufactures and delivers innovative human therapeutics. A biotechnology pioneer since 1980, Amgen was one of the first companies to realize the new science's promise by bringing safe and effective medicines from lab, to manufacturing plant, to patient. Amgen therapeutics have changed the practice of medicine, helping millions of people around the world in the fight against cancer, kidney disease, rheumatoid arthritis, and other serious illnesses. With a deep and broad pipeline of potential new medicines, Amgen remains committed to advancing science to dramatically improve people's lives. To learn more about our pioneering science and our vital medicines, visit www.amgen.com. Forward-Looking Statements This news release contains forward-looking statements that are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and assumptions that could cause actual results to differ materially from those described. All statements, other than statements of historical fact, are statements that could be deemed forward-looking statements, including estimates of revenues, operating margins, capital expenditures, cash, other financial metrics, expected legal, arbitration, political, regulatory or clinical results or practices, customer and prescriber patterns or practices, reimbursement activities and outcomes and other such estimates and results. 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Our products may compete against products that have lower prices, established reimbursement, superior performance, are easier to administer, or that are otherwise competitive with our products. In addition, while we routinely obtain patents for our products and technology, the protection offered by our patents and patent applications may be challenged, invalidated or circumvented by our competitors and there can be no guarantee of our ability to obtain or maintain patent protection for our products or product candidates. We cannot guarantee that we will be able to produce commercially successful products or maintain the commercial success of our existing products. Our stock price may be affected by actual or perceived market opportunity, competitive position, and success or failure of our products or product candidates. Further, the discovery of significant problems with a product similar to one of our products that implicate an entire class of products could have a material adverse effect on sales of the affected products and on our business and results of operations. The scientific information discussed in this news release related to our product candidates is preliminary and investigative. Such product candidates are not approved by the U.S. Food and Drug Administration (FDA), and no conclusions can or should be drawn regarding the safety or effectiveness of the product candidates. Only the FDA can determine whether the product candidates are safe and effective for the use(s) being investigated. Further, the scientific information discussed in this news release relating to new indications for our products is preliminary and investigative and is not part of the labeling approved by the FDA for the products. The products are not approved for the investigational use(s) discussed in this news release, and no conclusions can or should be drawn regarding the safety or effectiveness of the products for these uses. Only the FDA can determine whether the products are safe and effective for these uses. Healthcare professionals should refer to and rely upon the FDA-approved labeling for the products, and not the information discussed in this news release. FOSAMAX is a registered trademark of Merck & Co., Inc. i Johnell O, Kanis JA. Osteoporosis Int. 2006; 17:1726-1733. ii Burge R, et al. J Bone Miner Res. 2007; 22:465-475 iii "Osteoporosis Fast Facts.” Washington (DC): National Osteoporosis Foundation. Accessed at http://www.nof.org/osteoporosis/stats.html. iv "Economic Cost of Cardiovascular Diseases.” Dallas (TX): American Heart Association. Accessed at http://www.americanheart.org/statistics/10econom.html. v Lippuner K, et al. "Incidence and direct medical costs of hospitalisations due to osteoporotic fractures in switzerland.” Osteoporosis International. 1997;7:414-25.