September 9, 2011
I am Dr. Diana Zuckerman, president of the NationalResearchCenter for Women & Families and the Cancer Prevention and Treatment Fund. Our Center does not accept funding from pharmaceutical companies, so I have no conflicts of interest.
Our nonprofit Center analyzes and reviews research on a range of health issues, and provides objective and understandable information to patients and providers. My perspective is as a former faculty member at Vassar and Yale and research director at Harvard. I am also currently a fellow at the University of Pennsylvania Center for Bioethics.
I was trained in epidemiology at YaleMedSchool, so my perspective is to focus on meaningful data – real proof of benefits and risks. I urge you to do the same. Regarding benefits, we should focus on the data on the reduction or increase of fractures, especially fractures that affect people’s health, not on bone density or asymptomatic fractures.
You’ve heard a lot of different versions of what the data show, but if you focus on the meaningful data, not bone density, there is no proof of any benefits for bisphosphonates taken for more than 5 years. But there is evidence of harm, even after 3 years. And the longer these drugs have been on the market, the more we have learned about serious risks. That is a pattern that is of great concern, even in the absence of conclusive data.
Regarding cancer risk, the evidence is not clear but a possible risk is credible. Most cancers take about 15 -20 years to develop. By the time we find out if bisphosphonates increase the risk of esophageal cancer, it will be too late for many of the women taking the drugs to do anything useful with that information.
We clearly need better long-term studies to determine exactly what the long-term risks and benefits are. Meanwhile, we need labels that make it clear that these products have no proven benefits associated with taking them for more than 5 years, and have evidence of risk if taken more than 3 years.
But we need better long-term data. How are we to get those data?
It is easy to ask companies to conduct post-market studies, but not so easy to get them to do those studies in a timely manner, and to collect all the data required. The incentive isn’t there. That’s why revising the label to restrict the use of these drugs is so important. If the companies can prove that their drugs are more effective if taken for more than 5 years, or can prove that those benefits outweigh the risks, then the label can be changed in the future to reflect those findings. Until then, the label should warn about the risks after 3 years, and the lack of clear benefits associated with taking them for more than 5 years.