Patients who start and eventually stop regimens of a common class of osteoporosis drugs called bisphosphonates may be unable to benefit from parathyroid hormone (PTH), which can rebuild bone mass lost due to advanced stage osteoporosis. PTH has been proven to increase the volume and strength of the honeycomb-like bone infrastructure, the inner mesh that begins to diminish in old age.
Bisphosphonates, the active ingredient in widely prescribed osteoporosis medications such as Fosamax, Actonel, and Boniva are currently taken by more than thirty million Americans.
"These medicines work by preventing further bone loss," explains Dr. Warren Levy, president and CEO of Unigene Laboratories, Inc. "However, recent reports suggest that some patients using bisphosphonates may be unable to repair or replace older or damaged bone. Furthermore, it has been reported that the prior use of certain bisphosphonates may blunt the effects of PTH, which could render the only currently available bone growth drug ineffective. Since bisphosphonates typically deposit in the bones for years, the use of a bisphosphonate could compromise the ability to grow new bone later in life when it is most needed."
Estrogen alternatives have grown in recent years, including calcitonin, a naturally occurring hormone involved in calcium regulation and bone metabolism. In third-party clinical trials, calcitonin demonstrated a 62% reduction in the incidence of new vertebral fractures for a subgroup of women over seventy-five years of age, one of the most significant reductions demonstrated by any current osteoporosis therapy.