Shots for Osteoporosis — Convenient, Expensive, & Possibly Dangerous

Printer-friendly versionSend to friend Share this
Women's Health Activist Newsletter
November/December 2009

By Cindy Pearson

Some day soon, you may be offered a shot for osteoporosis. If you’re a woman who is already being treated for osteoporosis, or who has been being encouraged to take medication to prevent bone loss, the prospect of a shot may seem very appealing. After all, none of us like taking pills, and it really can be difficult to remember to do so — whether the pill needs to be taken once a day or once a week. And, if you add to those issues the uncomfortable side effects of osteoporosis pills, well then, it’s easy to want to forget taking those pills.

So, it’s no surprise that creative researchers have come up with a shot for osteoporosis. But, as with all new drugs, NWHN believes that women’s first question should not be “How do I take it?” but, rather, “Do I need it?” followed quickly by, “How safe is it?”

If you’ve already started talking with your clinician about osteoporosis, you’re likely to be over 50. The age factor is important, because aggressive marketing of drugs to the over-50 crowd has made it harder for curious patients to get an answer to the question of whether they even need a particular drug.

It used to be that drugs weren’t prescribed to patients until a diagnosis was established and it was clear that a specific medication would help with that particular diagnosis. You had a problem, you saw a doctor or a nurse practitioner, he or she worked with you to figure out your problem, diagnosed it, and prescribed treatment. But, the simple days of “diagnosis first, prescription after” have gone the way of rotary dial telephones. Now it’s “risk factor first, prescription next, drugs for many years, and diagnosis maybe never.” “Diagnosis maybe never” could be considered a success of all those years of drug treatment. But, what if something else bad happens along the way as a result of all those years of drug treatment? What if preventive drugs are actually harmful? Then the “risk factor first, prescription next, diagnosis maybe never” approach doesn’t make so much sense.

That’s the dilemma facing many women over age 50. Being diagnosed with osteoporosis means that one’s bones fracture easily because they’ve become weak, either due to age or to a medical condition. Osteoporosis is a real danger for women, and has several risk factors. In recent years, however, loss of bone density has morphed into being viewed as the primary risk factor for osteoporosis. (“Low bone density” means that an individual’s bones are less dense than average.) The view that bone density is the one and only risk factor for osteo, and that women with low bone density either have, or will soon develop, osteoporosis, has been widely promoted by marketers of osteo drugs.

Because scanning bones to assess their density is easy and relatively inexpensive, it is now a very popular strategy being heavily promoted by osteoporosis drug manufacturers. These manufacturers have bought scanning machines and given them to physicians for free; they’ve paid groups to create guidelines that recommend all women begin bone screening at age 50. They’ve even paid non-profit organizations to publicize toll-free numbers for women to call for the location of a nearby screening machine. Yet, while bone density can be measured, the bone’s strength — and therefore the likelihood of experiencing a bone fracture — cannot be measured.

Therefore, the Network encourages women in their 50s to reject bone density screening. No independent, science-based organization recommends screening women under age 65. The youngest recommendation is age 60, for women who are thin. All of the guidelines that suggest one should start screening at age 50 have drug company money behind them.

If your only reason for taking an osteoporosis drug is because you have been diagnosed with low bone density, you probably don’t need the drug at all. You certainly don’t need to make a rushed decision about whether to use it or not. Take time to find out more about what makes women more likely to experience a bone fracture (family history, for example) and decide for yourself if you need the drug. So, let’s say you’ve thought through whether or not you need a drug for osteoporosis, and for you, the answer is yes. Will the shot be the right choice for you? (It’s not on the market yet, but may be soon.)

We wrote this article shortly after an FDA Advisory Committee meeting held in August 2009 about the shot for osteoporosis. Its chemical name is denosumab. The first thing the Network believes that women should know is that this shot is likely to be very expensive. For that reason alone, we don’t recommend women try denosumab until they’ve first tried other FDA-approved osteoporosis medications. There are several, including bisphosphonates and selective estrogen receptor modulators (SERMs), and a variety of brands of each type. Most women will be able to find something that works for them, without needing to consider denosumab.

Some women can’t take bisphosphonates or SERMS, because of side effects or contraindications. These women still need safe and effective treatment for osteoporosis. What do we know about the safety and effectiveness of denosumab? It was studied in 7,800 postmenopausal women who had osteoporosis and who were 72 years old, on average. Women were given shots of either denosumab or a placebo every six months for three years. When the results were analyzed, women given denosumab had increased bone density and had experienced fewer bone fractures, when compared to the women given placebo shots. During the three-year study period, 0.7% of women on denosumab had a hip fracture versus 1.2% of women on placebo. There were also lower rates of less serious fractures in women who were given denosumab. Similarly, a smaller study of younger post-menopausal women (average age 58) also showed that denosumab prevents bone loss even when fractures aren’t likely to occur.1

These are good effectiveness results. But, denosumab also caused significant health problems for women in these studies, including ovarian and cervical cancer, pancreatic cancer, breast cancer recurrences, and serious infections that required hospitalization. While the numbers of cancers were too small to say with certainty that they were caused by denosumab, the risk of serious infection seems to be real.

Clearly, denosumab is not completely safe, so the question becomes whether or not the benefits of using it outweigh the risks. The numbers show that about 0.7% more women on denosumab had a serious infection than did the women on placebo — exactly the same fraction of women who avoided a hip fracture. The aftermath of a hip fracture is very serious and some women never fully recover from it, but serious infections can be very dangerous, too, and led to at least one death in the denosumab studies.

In response to this dilemma, the Network told the FDA Advisory Committee that we did not think that the benefit of denosumab outweighed the risks, at least not yet. Any time a drug is being considered for long-term use by many people who will never benefit from it, information about its safety needs to be weighed very heavily. We believe that women deserve more information about the possible risk of cancer caused by denosumab, and that this information will only emerge as the participants in the clinical trials are followed for a long time.

At the end of the Advisory Committee meeting, the members expressed their opinion that the benefit of preventing a hip fracture in an older woman by treating her osteoporosis with denosumab may be worth the risk of her getting a serious infection, and worth the possible risk of cancer. The members did not believe, however, that denosumab is safe enough to be approved for use by younger, post-menopausal women who do not have osteoporosis. The FDA is expected to issue its decision on denosumab later this year. The Network will continue to advocate to the FDA that the agency take enough time before approving denosumab to ensure that women have all the information they need about it.

References:

1. Background Document for Meeting of Advisory Committee for Reproductive Health Drugs (August 13, 2009) http://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/Drugs/ReproductiveHealthDrugsAdvisoryCommittee/UCM176595.pdf