THOUSAND OAKS, California, March 23, 2011 /PRNewswire/ -- Amgen today announced new long-term data showing that during the fourth and fifth years of Prolia(R) (denosumab) treatment, postmenopausal women with osteoporosis receiving Prolia continued with further, statistically significant, year-over-year increases in lumbar spine and total hip bone mineral density (BMD), a key measurement of bone strength. The overall adverse event profile was similar for the fourth and fifth years of consecutive Prolia treatment.

The data, which were presented at the annual European Congress Osteoporosis and Osteoarthritis (ECCEO11-IOF) in Valencia, Spain, showed that treatment with Prolia, the first and only approved RANK Ligand inhibitor for the treatment of postmenopausal osteoporosis, resulted in robust BMD gains after five continuous years of treatment (13.7 percent for lumbar spine BMD and 7.0 percent for total hip BMD).

The FREEDOM Study and the 5-Year Prolia Data

The pivotal FREEDOM (Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months) study established the efficacy and safety of Prolia based on three years of data from approximately 7,800 postmenopausal women. The open-label extension of FREEDOM is evaluating the long-term (up to 10 years) efficacy and safety of Prolia in 4,550 postmenopausal women. Seventy percent of eligible women from the FREEDOM study continued enrollment in the extension study; 2,343 women continued to receive Prolia treatment, and 2,207 transitioned from placebo to Prolia.

Continued treatment with Prolia resulted in consistent year-over-year gains in BMD at the lumbar spine and total hip. In years 4 and 5 respectively, women taking Prolia experienced further 1.9 percent and 1.7 percent increases in lumbar spine BMD and further 0.7 percent and 0.6 percent increases in total hip BMD (all P<0.0001 compared with extension baseline).

The incidences of new osteoporotic fractures also remained low for women taking Prolia for five years.

The women who transitioned from placebo to Prolia in the extension study showed significant BMD increases during the first two years of Prolia treatment: 7.9 percent increase in lumbar spine BMD and 4.1 percent increase in total hip BMD (all P<0.0001 compared with extension baseline).

Rates of adverse events (AEs) were 83.4 percent for women who continued on Prolia and 82.8 percent for women transitioned from placebo to Prolia. Rates of serious AEs were 18.9 percent and 19.4 percent for the two groups respectively. Two subjects in the group that transitioned from placebo to Prolia had AEs adjudicated to osteonecrosis of the jaw (ONJ) that healed without further complications. One of these subjects continued Prolia, and one subject discontinued. No atypical femoral fractures were reported in either group.

Osteoporosis: Impact and Prevalence

Referred to as a "silent epidemic" by the International Osteoporosis Foundation (IOF), osteoporosis is a global problem that is increasing in significance as the population of the world both increases and ages. The World Health Organization has officially declared osteoporosis a public health crisis, and the IOF is urging governments worldwide to make osteoporosis a healthcare priority.

Osteoporosis-associated fractures are a significant cause of mortality and morbidity. In 2000, the number of osteoporotic fractures in Europe was estimated at 3.79 million, of which 890,000 were hip fractures.(1) Since 2001, the incidence of hip fractures in European countries has risen significantly.(2) In the United States (U.S.), the number of fractures due to osteoporosis is expected to rise to more than three million by 2025.(3)

The direct medical cost of osteoporotic fractures in Europe is expected to rise from euro 31.7 billion in 2000 to euro 76.7 billion in 2050.(4) In 2005, osteoporosis-related fractures were responsible for an estimated $19 billion in cost in the U.S., and this cost is expected to rise to approximately $25 billion by 2025.(5)