Ibandronate

Ibandronate is a drug that is prescribed to postmenopausal women to treat osteoporosis and prevent bone loss. It decreases the chance of fractures by decreasing the breakdown of bone, and by increasing bone mass in many women. It is available by prescription only, and is administered either in tablet form or in an injectible form.

Template:Infobox Drug

Uses/Indications

Ibandronate is used to treat or prevent osteoporosis in women after menopause. It may increase bone mass by slowing loss of bone in most women who take it, even though they won't be able to see or feel a difference. Ibandronate may help lower the chances of breaking bones (fractures).

Osteoporosis

Osteoporosis is a disease in which bones become fragile and more likely to break. If not prevented or if left untreated, osteoporosis can progress painlessly until a bone breaks. These broken bones, or fractures, occur typically in the hip, spine, and wrist.

Normal bone versus bone affected with osteoporosis

Any bone can be affected, but of special concern are fractures of the hip and spine. A hip fracture almost always requires hospitalization and major surgery. It can impair a person's ability to walk unassisted and may cause prolonged or permanent disability or even death (usually due to other conditions that come about due to the immobility associated with hip fractures, such as pneumonia or a blood clot in the lung). Spinal or vertebral fractures also have serious consequences, including loss of height, severe back pain, and deformity.

According to a 2004 report by the US Surgeon General on Bone Health and Osteoporosis, this bone disease is the most common cause of fractures. Roughly 10 million individuals over age 50 in the United States have osteoporosis of the hip. An additional 33.6 million individuals over age 50 have low bone mass or “osteopenia” of the hip and thus are at risk of osteoporosis and its potential complications later in life. Due primarily to the aging of the population, the prevalence of osteoporosis and low bone mass is expected to increase. By 2020, one in two Americans over age 50 is expected to have or be at risk of developing osteoporosis of the hip; even more will be at risk of developing osteoporosis at any site in the skeleton.

Mechanism of Action

The relationship between osteoblasts and osteoclasts in bone remodeling

Bone is in a constant state of remodeling. Osteoblasts are bone cells that help with bone formation, and osteoclasts are bone cells that break down bone. During childhood and until the age of approximately 30, bone formation exceeds bone breakdown, or resorption, then, as part of the natural aging process, bones begin to break down faster than new bone can be formed and bone loss occurs. In women, bone loss accelerates after menopause, when the ovaries stop producing estrogen--the hormone that protects against bone loss. Ibandronate works by inhibiting the activity of the cells responsible for bone resorption, called osteoclasts, thus slowing the removal of bone.

Side Effects

The following are some serious side effects associated with the use of idandronate:

• pain or trouble with swallowing
• chest pain
• very bad heartburn or heartburn that does not get better

Oral administration

• pain or trouble swallowing (dysphagia)
• heartburn (esophagitis)
• ulcers in the stomach or esophagus (the tube that connects the mouth and stomach)
• diarrhea
• pain in extremities (arms or legs)
• upset stomach (dyspepsia)

Intravenous administration

• transient bone or muscle pain
• influenza-like symptoms

Complications and Warnings

Several conditions preclude the use of ibandronate:

• Low blood calcium (hypocalcemia).
• cannot sit or stand up for at least 1 hour (60 minutes) after taking ibandronate.
• kidneys that work very poorly.
• allergy to ibandronate sodium or any of the other ingredients of ibandronate.

Ibandronate may cause serious problems in the stomach and the esophagus, such as trouble swallowing, heartburn, and ulcers. The risk of developing these reactions is reduced if ibandronate is taken with a full glass of water, and if the patient remains upright for at least 60 minutes after taking it. This helps ensure that the tablet does not get stuck in the esophagus or stay there for longer than necessary.

Some medicines, especially certain vitamins, supplements, and antacids can prevent ibandronate from getting to the bones. This can happen if other medications are taken too close to the time that ibandronate is taken.

Administration

Ibandronate is available in tablets of 2.5 mg or 150 mg. The lower dose is given daily and the higher dose is given monthly. Typically, ibandronate is taken in the morning at least one hour before eating and before taking other medications. Some side effects are minimized if ibandronate is taken with a full glass (6 to 8 ounces) of plain water (not mineral water).

Ibandronate is also available as and injection administered once every 3 months. Intravenous ibandronate is as effective as the tablet form, but has fewer gastrointestinal side effects that are associated with swallowing a pill.

Effectiveness

In postmenopausal women with osteoporosis, ibandronate has been found to increase bone mineral density and decrease the amount of vertebral fractures. Ibandronate is also effective in slowing bone loss in women who are at high risk for developing osteoporosis. Risk factors include a family history of osteoporosis, high bone turnover, decreased bone mineral density, previous fractures, thin body frame, being Caucasian or Asian, and smoking.

Controversy

In January 2006, the makers of Boniva were subject to a false claims lawsuit filed by manufacturers of a rival drug, Actonel. The makers of Actonel claimed that ads for Boniva were misleading because they made claims about the effectiveness of Boniva that were not justified by findings in clinical trials. In September of the same year, the injunction was rejected by a judge who thought the claims were unjustified and unfair.

Research

Click here for a list of research trials involving ibandronate.

References

External Links

• Food and Drug Administration: Consumer Information Sheet: Boniva

• Roche U.S. Pharmaceuticals: Boniva