Studies look at ways to sequence, cycle osteoporosis drugs

Researchers seek new approaches to maximize the potential of treatments to build up bones or slow bone loss.

By Victoria Stagg Elliott, AMNews staff. Sept. 19, 2005.

The two classes of osteoporosis drugs currently on the market -- one that builds bone and one that slows bone breakdown -- don't always work well together. But two papers published last month in the New England Journal of Medicine say this circumstance could be just a matter of timing.

Several studies have suggested that taking bisphosphonates and parathyroid hormone together might dull both treatments' efficacy, but these new studies showed that cycling or taking the drugs in sequence could lead to more satisfactory results.

"They're both good studies," said Robert Recker, MD, who wrote an accompanying editorial and is the director of the Osteoporosis Research Center at Creighton University in Omaha, Neb. "We need to figure out the best way to manage patients to get the best out of both medications."

One study involved 126 women already taking the bisphosphonate alendronate long term to reduce bone turnover. Participants were randomized into three groups. The first continued on this drug alone. The second group took alendronate and also received daily injections of teriparatide, a form of parathyroid hormone, continuously for 15 months. The third also took both drugs daily but injected the parathyroid hormone on a three-month on-again, off-again cycle.

Both groups receiving the hormone built more bone than the group that was only on alendronate. The group that cycled, however, did not re-absorb bone as much as the group that received non-stop hormone injections.