Long-Term Bisphosphonate Side Effects May Include Esophageal CancerApr 3, 2012 | Parker Waichman LLP
Evidence continues to mount that long-term use of oral bisphosphonates, including Fosamax, could lead to serious consequences continues to mount. One of those possible consequences could be the development of esophageal cancer.
According to the U.S. Food & Drug Administration (FDA), approximately 5 million Americans use oral bisphosphonates like Fosamax. They are mostly used for the treatment and prevention of osteoporosis in post-menopausal women. Other approved indications include treatment to increase bone mass in men with osteoporosis, treatment and/or prevention of glucocorticoid-induced osteoporosis, and Paget’s disease.
Case reports have suggested an association between use of oral bisphosphonates for osteoporosis and increased risk of esophageal cancer, but definitive proof is lacking. It had long been assumed that Fosamax and other bisphosphonates could safely be taken indefinitely, but as side effects have mounted, that assumption has been challenged. Unfortunately, most studies of bisphosphonates have only looked at the drugs for a few years.
In 2010, the FDA added information to the Warnings and Precautions section of the drugs' labels describing the risk of atypical thigh fractures. As we reported previously, there have been hundreds of reports of atypical thigh fractures occurring in patients taking bisphosphonates, often for longer than five years.
In September 2010, a study published in the British Medical Journal found that people who had taken the oral bisphosphonates over five years had twice the risk of developing esophageal cancer. The study analyzed data from the UK General Practice Research Database, which has anonymised patient records for around six million people. The researchers focused on men and women 40 years old, 2,954 of whom had esophageal cancer. Another 2,018 had stomach cancer, while 10,641 had colorectal (bowel) cancer. All of the subjects were diagnosed between 1995 and 2005. The study found that those with 10 or more prescriptions for oral bisphosphonates, or with prescriptions over about five years, had nearly double the risk of esophageal cancer compared with people with no bisphosphonate prescriptions. No increase risk was seen with colorectal or stomach cancer.
The FDA is currently conducting an on-going review of the possible link between oral bisphosphonates and esophageal cancer. In a Drug Safety Communication issued in September 2010, the agency noted that studies on possible link have been conflicting, and it has been unable to reach a conclusion thus far. While the FDA said it believed the benefits of bisphosphonates continued to outweigh their risks, it acknowledged that further study of the issue was needed.