Amgen has presented new long-term data which shows that women with osteoporosis who have been treated Prolia for up to five years experienced statistically significant, year-over-year increases in lumbar spine and total hip bone mineral density.

The 4,550-patient follow-up data, which were presented at the European Congress on Osteoporosis and Osteoarthritis  in Valencia, Spain, showed that treatment with Prolia (denosumab), a first-in-class, fully human monoclonal antibody designed to target RANK ligand, resulted in "robust BMD gains after five continuous years of treatment", ie 13.7%for lumbar spine BMD and 7.0% for total hip BMD.

In years 4 and 5 respectively, women taking Prolia experienced further 1.9% and 1.7% increases in lumbar spine BMD and extra 0.7%and 0.6% increases in total hip BMD. Amgen also noted that the incidences of new osteoporotic fractures also remained low for women taking Prolia for five years. Also, the women who transitioned from placebo to Prolia in the extension study showed significant BMD increases during the first two years of treatment: 7.9% in lumbar spine BMD and 4.1% in total hip BMD.

The biotech major noted that two subjects in the group that switched from placebo to Prolia had  suffered from osteonecrosis of the jaw but they healed without further complications.

More compliance with denosumab than alendronate

Amgen also reported data from another new two-year study, which showed postmenopausal women with osteoporosis had "significantly greater adherence, compliance, and persistence" with Prolia than those on alendronate, the oral bisphosphonate commonly used to treat osteoporosis and sold by Merck & Co as Fosamax.

Results from the DAPS study also presented in Valencia, also found that more than 90% of patients preferred Prolia (an injection) over alendronate (a tablet).