Am Fam Physician. 2006;73(2):305-306
Synopsis
Ibandronate (Boniva) is the newest oral bisphosphonate approved for the treatment and prevention of osteoporosis in women who are postmenopausal. It is the first drug in its class that can be taken daily or monthly.
| Name | Starting dosage | Dose form | Approximate monthly cost* |
|---|---|---|---|
| Ibandronate (Boniva) | 2.5 mg daily | 2.5− or 150-mg tablets | $78 (either dosage) |
| 150 mg monthly |
Safety
Ibandronate, like other bisphosphonates administered orally, may cause esophagitis, esophageal ulcer, or gastric ulcer. These risks may be increased in patients taking concurrent nonsteroidal anti-inflammatory drugs. Ibandronate is not recommended for use in patients with severe renal impairment and has not been studied in patients with hepatic impairment.1 The U.S. Food and Drug Administration has classified ibandronate category C for use during pregnancy.
Tolerability
Adverse effects with ibandronate most commonly are gastrointestinal and include dyspepsia, gastroenteritis, and nausea. They are comparable to the adverse effects of other drugs in the same class.2,3 In two clinical trials, 7 percent and 7.5 percent of participants in the ibandronate 2.5 mg daily groups dropped out because of medication-related adverse effects.2,3 Adverse effects that were reported in greater than 5 percent of patients taking ibandronate included back pain, headache, bronchitis, and myalgias. The overall adverse-effect profiles of the daily and monthly preparations were similar.4
Effectiveness
There are many questions regarding the effectiveness of ibandronate in preventing outcomes of importance to patients. Daily ibandronate was compared with placebo in 2,929 postmenopausal women with a prior vertebral fracture.3 Treatment decreased the absolute risk of new, symptomatic, radiographically confirmed vertebral fracture from 5.3 to 2.8 percent over three years (absolute risk reduction 2.3 percent; number needed to treat = 43 for three years).3 There was no difference in the likelihood of clinical nonvertebral fracture between placebo and ibandronate. The 2.5-mg daily and 150-mg monthly dosages of ibandronate were equivalent in terms of percent change in lumbar spine bone mineral density from baseline to one year. The effects of ibandronate on rates of hip fracture, death, and symptomatic vertebral fracture have not been assessed.4 Data on the fracture prevention of ibandronate in patients with osteoporosis but without previous fracture are lacking.5 No bisphosphonate has been compared with adequate doses of calcium and vitamin D.5
Price
The cost of ibandronate is approximately $78 per month for either dosage. Weekly alendronate (Fosamax) costs $77 per month and weekly risedronate (Actonel) costs $74 per month.
Simplicity
Ibandronate can be taken once daily or once monthly, similar to the daily or intermittent formulations of alendronate and risedronate. It should be taken only with water, at a time when the patient will be able to remain upright for one hour following the dose, and should not be taken within one hour of eating or of ingesting any other medication. Products containing calcium, aluminum, magnesium, or iron (e.g., milk, many foods, antacids) interfere with absorption of ibandronate. Thus, monthly dosing may be more convenient for some patients.
Bottom Line
Ibandronate is a bisphosphonate that can be taken daily or monthly. The daily dosage has been shown to decrease vertebral fractures in women with osteoporosis and a history of previous vertebral fractures. Neither formulation has been shown to reduce the risk of hip fracture or other nonvertebral fracture, nor to reduce fractures in women without prior fracture. Ibandronate has not been compared directly with other bisphosphonates or with adequate daily doses of calcium and vitamin D. The convenience of monthly dosing needs to be balanced against the lack of data on fracture prevention.