Men's Osteoporosis Support Group
Two recent denosumab review studies
Horm Metab Res. 2009 Jun 17. [Epub ahead of print]. Efficacy and Safety of Denosumab in Postmenopausal Women with Osteopenia or Osteoporosis: A Systematic Review and a Meta-analysis. Anastasilakis AD. PMID: 19536731. This article is a meta-analysis of the recent research on denosumab as a treatment for osteoporosis, with all research currently being done on postmenopausal women. Denosumab is an antibody to receptor activator of nuclear factor-kappaB ligand (RANKL), which is involved in osteoclast formation and function. In summary, denosumab is a bone antiresorptive agent, which thereby leads to increased bone formation. Bone formation stays the same, bone resorption is decreased, with a net long-term increase in bone as the end result.
The authors found nine randomized controlled trials (RCTs) that included 10,329 women. They found denosumab effective at reducing markers of bone resorption and that it increased lumbar and hip bone mineral density (BMD). But they also found that denosumab was not associated with a significant reduction in fracture risk and that participants on denosumab had increased risk of serious adverse events and serious infections. They noted, "In conclusion, although effective as an antiresorptive agent, denosumab has not yet proved its efficacy on fracture risk reduction while increased infection risk questions its safety."
Curr Opin Rheumatol. 2009 Jul;21(4):369-73. Denosumab update. Lewiecki EM. PMID: 19424068. This is also a 2009 review of the recent literature on denosumab. It's findings are, however, different from those stated in the Anastasilakis and others study above. Lewiecki notes that denosumab, "reduces fracture risk in women with postmenopausal osteoporosis" and that, "Adverse events and serious adverse events, including infections and malignancy, are generally similar in patients treated with denosumab compared with those receiving placebo or alendronate."
Editor's comments. So the results from these two review studies are conflicting, leaving readers to wonder what the facts are regarding denosumab. Since it is not yet FDA-approved, we have to leave these issues up to the FDA to resolve. Hopefully there will be more research results in the mean time, or the FDA findings will be explanatory, if they approve it. Here is a recent Update with more details on how denosumab works and some of the early research results. Note that it is given via twice-yearly injections, a very nice feature if it is eventually proven effective and safe, and receives FDA approval.