The Food and Drug Administration (FDA) has announced that it is looking into reports that Glaxo Smith Kline’s prostate drug Avodart and Merck & Co’s prostate drug Proscar may be contributing to an increase of male breast cancers.
Avodart and Proscar are used to treat baldness besides the “off label” use in prostate cancer as a drug that shrinks the size of the prostate prior to radiologic therapy and as a part of hormone therapy (ADT).
This is only an investigation; the FDA has not concluded that either drug poses any breast cancer risk.
Merck spokeswoman (Proscar) Pam Eisele said the prescribing instructions for Proscar already mention cases of male breast cancer seen in clinical trials. However, she said that “A causal relationship has not been established.”
Glaxo spokeswoman (Avodart) Sarah Alspach said the company evaluates all reported cases of breast cancer in men taking Avodart. She said that, “Based on reports evaluated to date, there is not conclusive evidence of a causal association between Avodart and male breast cancer.”
The investigation has been triggered by information supplied to the FDA through its Adverse Event Reporting System (AERS) Database for the period of October – December 2009.
I want to emphasize that the appearance of a drug on the database does not mean that FDA has concluded that the drug has the listed risk. It means that FDA has identified a potential safety issue, but does not mean that FDA has identified a causal relationship between the drug and the listed risk.
Once the FDA concludes the investigation and if it determines that the drug is associated with the risk, it may take a variety of actions. These potential actions include requiring changes to the labeling of the drug, requiring development of a Risk Evaluation and Mitigation Strategy (REMS), or gathering additional data to better characterize the risk.
FDA is not suggesting prescribers stop perscribing the drugs or that patients taking the drug should stop taking the medication. Patients who have questions about their use should contact their health care provider. When the evaluation is completed, the FDA will release its findings and if needed new prescribing directions.
What does this mean if you are taking a 5-alpha reductase inhibitor? Should you stop taking it? If your doctor suggests that you start it, should you?
My personal opinion is that all drugs always pose extra risks; your decision needs to be balanced against what you feel the advantages you are getting from the drug. In my case, I am not currently taking any of these drugs and intermittent ADT has done a good job controlling my cancer. In my case, I don’t see the potential risk out weighing the reward, so I am not planning to add these drugs. If the FDA still has not concluded their analysis and ADT starts to fail, I will give serious consideration to adding a 5-alpha reductase inhibitor.
If you are taking a 5-alpha reductase inhibitor (actually all of us should) you need to do a breast self-exam along with a testicular exam. Every American women has been taught to perform a self-breast exam, but I don’t know any man who has ever been taught. Next doctor appointment ask for help and learn how to perform an exam, it is even more important for men taking a 5-alpha reductase inhibitor.
Joel T Nowak, MA, MSW
May 12, 2010