So far in the arsenal of bone health drugs used to treat osteoporosis we have, Evista (raloxifene); bisphosphonates such as Fosamax (alendronate), Actonel (risedronate), Boniva (ibandronate), and Reclast (zoledronic acid); Forteo (teripartatide); and Miacalcin (calcitonin). All have their established efficacy and their associated adverse effects. Evista is not that effective and causes hot flashes and has the risk for thromboembolism. Forteo is effective at increasing bone density and reducing fracture risk, but use is limited to two years. The bisphosphonates carry the largest amount of controversy with them, those being: osteonecrosis of the jaw; renal failure with IV administration of Reclast; and atypical fractures of the femur. There are also concerns with use beyond 5 years, not knowing if the drugs are safe and still yet effective. Miacalcin (calcitonin) is not as effective as the bisphosphonates but has minimal side-effects and can be useful as an adjunct in those with back pain from vertebral crush fractures. Now I will be the first one to state that we rely too heavily upon the use of drugs to reduce the risk of a fracture, and the most effective fracture risk-reduction strategy, especially in the old-old population, is fall risk-reduction (fall prevention). The approach needs to be multi-factorial, looking at a comprehensive assessment for fall risk factors, and engaging the person to address those risk factors, whether they be poor balance, medications, home safety issues, leg weakness, etc. But for those with high-fracture risk due to low bone density, where drug treatment is justified, along with the multi-factorial approach to reducing fall risk, there is now Prolia.
Prolia (denosumab) is a monoclonal antibody which is very effective at increasing bone density, at least as effective as bisphosphonates and Forteo. It is easily administered by a subcutaneous injection (fatty tissue under the skin) twice a year. Many of the side-effects seen with bisphosphonates are not there, and the complexity of taking an orally administered bisphosphonate clearly disappears with an injection. The drug-drug interaction between proton pump inhibitors, e.g. Prilosec and others, is non-existent, which otherwise render bisphosphonates ineffective. It also doesn’t have the risk for renal failure, as is seen with Reclast injection. There are some data that suggest eczema and serious skin infections may occur, and more needs to be known about that. However, Prolia has been on the market, for other uses and other names for about 8 years. So the safety data are quite well established. For those that have very low bone density, and are at high fall and fracture risk, Prolia just might be a very reasonable alternative, to combine with an effective fall prevention strategy.