New Osteoporosis Drug
The United States Food and Drug Administration has approved a new osteoporosis drug for the treatment of bone weakness in some postmenopausal women. The new medication, called Prolia, is targeted at women after menopause who are at high risk of bone fracture. The drug is administered as an injection, needed only twice a year. At the time of writing it was due to become available in June 2010.
Menopause And Bones
Our bones are constantly breaking down and renewing themselves, even though, for the most part, we're totally unaware of this process. The hormone estrogen plays a vital role in the ability of our bones to build themselves up again. Because estrogen levels fluctuate during menopause, and then remain low after menopause, postmenopausal women may have weaker bones that fail to rebuild. This can lead to a bone-weakening condition called osteoporosis. Women with this condition have a higher chance of breaking a bone. These are women who may benefit from taking Prolia.
How Prolia Works
Prolia is a form of biologic therapy. Basically, what this means is that it's a human antibody which has been artificially produced in a laboratory. Prolia impedes the breakdown mechanism of the bones by targeting a chemical signal called RANK Ligand.
RANK Ligand plays a key role in the natural bone breakdown process. When treated with Prolia, it simply works more slowly.
Candidates For Prolia
Prolia is not recommended for all postmenopausal women with osteoporosis. After 3 years of clinical trials, involving at least 30 separate trials and approximately 12,000 patients, the FDA has decided that Prolia should be prescribed only for the following women:
Postmenopausal osteoporosis patients with high risk of fracture, either because they -
a) have a history of previous fractures due to osteoporosis
b) have other, multiple fracture risk factors
Fracture risk factors in women with osteoporosis include: heavy smoking, a low body mass index and long-term glucocorticoid therapy, among others.
Prolia appears to reduce calcium levels in some women. Patients whose calcium levels are already low will not be recommended Prolia treatment.
The clinical trials of Prolia did expose some risks to patients as well as benefits. For example, because the action of Prolia not only slows bone breakdown but also slows bone remodeling, it may actually make it harder for fractures to heal, if and when they do occur despite a patient being in receipt of treatment with Prolia.
Other possible risks included:
Osteonecrosis of the jaw (permanent or temporary loss of blood supply to the jaw, causing bone damage)
Unusual bone fractures
Pain in the back, extremities, muscles and bones
Prolia may also have a negative effect on a patient's immune system, giving a higher risk of infections, including bladder infections.
The makers of Prolia say they have implemented a careful monitoring and information program as the drug becomes available for patient treatment. They believe that for some postmenopausal women, the benefits for Prolia outweigh the risks. The problems mentioned above by no means affect every Prolia patient. The FDA obviously agrees with Prolia's producers on this point.