Reader Question: I have been on all the medications on the market for osteoporosis, including the yearly IV medication, Reclast, and the daily injection, Forteo. Are there any new medications available, or soon to be available, that I can look forward to?
A very important drug trial result was released at the American Society for Bone and Mineral Research in Montréal, Quebec. This involved the long awaited biologic agent, Denosumab. This is hopefully, the last trial necessary before they can apply to the Federal Drug Administration (FDA) for approval.
How does the drug work?
Bone is constantly active with many cells involved in remodeling, the process of new bone replacing old bone. The cells that build the bone are called osteoblasts while the ones that break down the bone are called osteoclasts. Peak bone mass occurs at around age 30 and begins to favor the osteoclasts after menopause. This results in increased bone breakdown in the first years after one's menstrual cycle stops.
Denosumab stops these osteoclasts, the cells that break down the bone. It targets RANK ligand, a protein that these osteoclasts need to work. By stopping the breakdown of bone, it allows the osteoblasts, the builders to do their job and build the bone.
This agent is important as it involves a new pathway to treatment, one that is significantly different than any other one currently on the market.
What is a biologic agent and how is it given?
A biologic agent is a substance that is made from a living organism. It is given by injection under the skin twice a year.
Can you explain the trial and the results?
This was a phase lll clinical trial called the FREEDOM study. It involved a total of 7,868 women ages 60 to 90 from 32 different countries. In the trial, postmenopausal women with low bone mineral density received subcutaneous Denosumab every six months or a placebo (inactive or fake pill) for three years as well as 1,000 mg of elemental calcium and up to 800 IU of vitamin D daily.
At the conclusion the study showed that with Denosumab patients compared to placebo had a:
• 68% reduction of a new vertebral fracture.
• Reduction of non-vertebral fractures by 20%.
• Reduction of hip fractures 40%
• Increase in bone mineral density at the lumbar spine of 9% and 6% at the total hip
Were there any side effects?
With biologic agents there is a concern that they may increase the risk of cancer or infections. However, this large trial did not show that there was any increase in these or any other conditions compared to placebo.
In conclusion, the results from this trial were very impressive. The agent appears safe and as good, if not significantly better, than most agents currently on the market. Hopefully, with approval by the FDA, this drug will quickly become available to help patients treat their osteoporosis and decrease their risk of fractures.