Dueling Osteoporsis Drug Ads

Dueling Osteoporosis Drug Ads

The goal of osteoporosis drug therapy is not to stop bone loss or improve bone density. Rather it is to reduce the chance of having a serious fracture. Over the years, osteoporosis researchers have found that improving bone density does not always lead to fracture reduction. The drug class called bisphosphonates has dominated the osteoporosis drug market ever since Fosamax became available in 1994. Actonel, another bisphosphonate soon followed. Boniva is the latest drug in this class.

How good are these drugs at reducing the rate of hip fracture, the most serious consequence of osteoporosis? Not very. The first clinical trial proving Fosamax’s benefit showed that at three years, 1% of the drug-treated women had had a hip fracture, compared with 2% of the women on the placebo. Significantly, the elderly women in this trial all had evidence of a previous fracture; whereas many younger women are inappropriately put on long-term Fosamax purely because a bone-mineral density test showed bone loss.

As Fosamax nears the end of its patent life, its competitors, Actonel and Boniva, are promoted in ads that emphasize the fact that they do not have to be taken daily. For example, the TV and print ads for Boniva feature its once-a-month dose convenience, but the ads for once-a-week Actonel also mention its proven fracture-prevention. These two different promotional approaches merit scrutiny.

What did the clinical trials prove?

In a three-year trial, Boniva was no better than a placebo in reducing non-spinal fractures (hence the Boniva ads’ focus on once-a-month dosing). As for Actonel, its advertised claims are correct but misleading: “Actonel is clinically proven to help protect many bones where a woman is most vulnerable to fractures caused by osteoporosis: The spine and a combination [emphasis added] of wrist, hip, collarbone, upper arm, leg and pelvis.”

Clustering the non-spinal fractures together clearly makes the clinical trial results look more impressive. 11% rate of the women on a placebo had a non-spinal fracture, compared to 7% for the women on Actonel. However, where it concerns hip fracture, the same trials showed Actonel to be much less impressive. The rate of hip fracture of the women on Actonel was identical (2%) to that of the women on the placebo. (These findings appear in Actonel’s “label,” known as the packet insert which provides prescribing information for doctors.)

Who were the study participants?

In both the Boniva and the Actonel clinical trials, the participants were postmenopausal women with documented osteoporosis—that is, spinal fractures shown on x-ray—but only some had symptoms. In many cases, women are unaware of their spinal fractures.

Cautions

The bisphosphonates, particularly Fosamax and Actonel, are usually prescribed for five years or more. In her excellent Web site, Susan Ott, MD, one of the country’s leading osteoporosis researchers, explains why five years is enough. “The bisphosphonates get deposited in the bone and will accumulate for years. It is possible that many years of continuous medicine would make bone more brittle or impair the ability to repair damage. Bisphosphonates do reduce fractures and improve measurements of bone strength for the first five years in both animal studies and in women who have osteoporosis. After five years, the fracture rates are as high in the women who keep taking alendronate [Fosamax] as in the women who quit.” (http://courses.washington.edu/bonephys)

Alternatives:

Reduce the chances of falling by eliminating scatter rugs from the home and by avoiding certain prescription drugs like tranquilizers and barbiturates. Regular exercise will also reduce the risk of fracture. Daily supplements of 1000 mg calcium and 800 IU vitamin D3 decrease the likelihood of a first hip fracture, according to an analysis of relevant clinical trials published last year in the Journal of the American Medical Association. This is a lower amount of calcium and a higher amount of vitamin D than the longstanding recommendations.