THOUSAND OAKS, California, March 23, 2011 /PRNewswire/ -- Amgen today announced new data that showed postmenopausal women with osteoporosis had significantly greater adherence, compliance, and persistence during Prolia(R) (denosumab) treatment than during alendronate treatment, an oral bisphosphonate commonly used to treat osteoporosis.

Adherence to treatment, which includes both compliance (a measure of how well patients follow directions for taking medication) and persistence (a measure of whether patients continue with treatment), was measured over two years.

Results from the DAPS (Denosumab Adherence Preference and Satisfaction) study presented at the annual European Congress on Osteoporosis and Osteoarthritis (ECCEO11-IOF) in Valencia, Spain, also found that more than 90 percent of patients preferred Prolia as a treatment option over alendronate. In addition, significantly more patients were satisfied with denosumab injection compared with alendronate tablet (mean score of 4.5 vs. 3.2; score scale of 1-5, higher score, higher satisfaction, p<0.0001).

"Despite the availability of several treatment options, many postmenopausal women with osteoporosis are not taking their medication as prescribed and therefore remain at risk for fractures," said Professor Nick Freemantle, University of Birmingham, Birmingham, UK. "Prolia is an important treatment option for patients not only because of its efficacy and safety, but also because, as this study suggests, women may be more likely to stay on treatment compared to weekly oral alendronate."

DAPS Study Results

DAPS was a two-year, multicenter, open-label, crossover study of 250 postmenopausal women with a bone mineral density (BMD) T-score of less than or equal to -2.0 to greater than or equal to -4.0 at the lumbar spine, total hip, or femoral neck and no prior bisphosphonate treatment. Patients were randomized (1:1) to receive either Prolia every six months in year 1 followed by weekly oral alendronate in year 2, or receive alendronate in year 1 followed by Prolia in year 2.

In the study, 92.4 percent of the patients preferred Prolia over alendronate versus 7.6 percent who preferred alendronate (p<0.0001). Additionally, 91.2 percent preferred Prolia as a treatment option versus 8.8 percent for alendronate (p<0.0001), and overall significantly more patients were more satisfied with treatment with Prolia compared to treatment with oral alendronate.

In patients who received Prolia in the second year of the study, treatment with Prolia compared to alendronate was associated with significantly greater:

- adherence (92.5 percent vs. 63.5 percent, p<0.0001), - compliance (93.4 percent vs. 67.8 percent, p<0.0001), and - persistence (97.2 percent vs. 71.3 percent, p<0.0001) with treatment.

Patients were considered adherent to treatment if they received two Prolia injections within 6 months (plus or minus 4 weeks) apart, or took greater than or equal to 80 percent weekly oral alendronate and at least two alendronate tablets in the last month, and returned for the final study visit within an allotted time.

The incidence and types of adverse events (AEs) and serious adverse events (SAEs) were generally similar between the Prolia and alendronate patient groups. SAEs were reported in 3.5 percent and 3.9 percent of patients receiving Prolia and alendronate, respectively.

Osteoporosis: Impact, Prevalence and the Role of Adherence

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)

Postmenopausal women with osteoporosis who have experienced a fracture are at increased risk for another fracture.(6),(7),(8) Poor adherence can increase fracture risk and has been associated with more fracture-related hospitalizations.(9) Yet globally, adherence to osteoporosis treatments remains low.

- An analysis of data combined over multiple U.S. health plans showed that approximately 50 percent of patients discontinue oral bisphosphonate therapy within the first year.(10) - Data from the UK Health Improvement Network and General Practice Research Database showed that less than 50 percent of women in the UK continue osteoporosis therapy after six months.(11) - In Germany, the IMS(R) Disease Analyser database showed that compliance with medication helped reduce the risk for fracture, yet only one third of women in the database were still on treatment after one year.(12)