A new medication for osteoporosis prompts the body to rebuild bone and could potentially strengthen the skeleton against fractures, researchers report.

The experimental drug, romosozumab, frees the body's ability to stimulate bone production by blocking biochemical signals that naturally inhibit bone formation, explained Dr. Michael McClung, founding director of the Oregon Osteoporosis Center in Portland, Ore, Newsmax Health reports.

The new drug uses an antibody to block the function of sclerostin, a protein the body produces to naturally inhibit bone growth.

This phase 2 clinical trial involved more than 400 postmenopausal women aged 55 to 85 who had osteopenia, which is low bone mass that is not low enough to be classified as osteoporosis. They were randomly assigned to receive one of four treatments for a year: romosozumab; a placebo; or one of two current osteoporosis medications.

Results showed that romosozumab increased bone mineral density in the spine by 11.3 percent during the study period, compared with a 7.1 percent increase with teriparatide and alendronate - 4.1 percent.

"In terms of rebuilding bone mass, this is clearly better than Forteo or the bisphosphonates," said Dr. Robert Recker, president of the National Osteoporosis Foundation and director of the Osteoporosis Research Center at Creighton University in Omaha, Neb, who was not involved with the study.

The new drug also appears to be safe, with no major side effects reported, McClung said.

The drug is still several years from coming to market, McClung noted. Researchers have to prove to the U.S. Food and Drug Administration that it actually protects against bone fractures, which will require more research.