If you are among the people in America who agree with one or other of the following two statements, you need an immediate crash course in what approval of a new drug by the U.S. Food & Drug Administration (FDA) does actually mean:
FDA only approves drugs without serious side effects.
FDA only approves “extremely effective” drugs.
According to a recent survey conducted by Schwartz and Woloshin and just published in the Archives of Internal Medicine:
25 percent of 2,944 people surveyed did indeed believe that the FDA only approves drugs without any serious side effects.
39 percent of 2,944 people surveyed did indeed believe that the FDA only approves “extremely effective” drugs.
In fact, neither of these two things are true at all. So what is the truth?
In reality, FDA approval only implies that — after careful review — the agency has determined that “the benefits [of the approved agent] are judged to be greater than the harms. It doesn’t mean that they’re big and important,” said Woloshin in a statement to Reuters, which has also reported on this study.
Schwartz and Woloshin also assessed people’s perceptions about the relative value of newer and older medicines based on FDA approval. The two drugs used in this test actually had approximately equal efficacy and approximately the same side effects in the management of heartburn, but some 66 percent of those questioned picked the newer medication when asked to make a choice between the two.
In fact, in many cases, FDA approval is not based on direct comparisons of effectiveness and safety between drug X and drug Y, so there may be no good reasons to believe that one is any better or safer than the other. In the case of new cancer drugs, the FDA does try hard to encourage drug developers to carry out trials that compare a new drug to the “standard of care” at the time a new trial is being designed, but it is not always possible to do this, and events may overtake reality.
As an example, it would be nice to know whether MDV3100 is or is not safer or more effective than abiraterone acetate in the treatment of castration-resistant prostate cancer (CRPC). However, abiraterone acetate wasn’t approved at the time the Phase III trials of MDV3100 were being designed. At that time, the standard of care for any man with CRPC — metastatic or otherwise — was still chemotherapy with docetaxel + predisone. Unless either the survival benefit demonstrated by MDV3100 is a lot more or a lot less than 3.9 months compared to placebo, or the side effects of MDV3100 are a lot worse or a lot better than those exhibited by patients on abiraterone acetate compared to placebo, there will be no way to assess whether one drug is any “better” than the other. For very similar reasons, we have no idea of the relative merits of treating men with CRPC with either abiraterone acetate of sipuleucel-T.
The FDA does its best to ensure that important new drugs for conditions like prostate cancer are moved through the regulatory process in a timely manner. In recent years, they have become pretty successful at this. However, we are likely, over time, to discover than some of these new drugs have additional, and potentially significant, side effects that were simply not seen or reported in the relatively small numbers of patients who participate in the clinical trials that customarily lead to drug approval.
Here is a brief list of some very simple things that it is well worth understanding about what an FDA approval of a new drug actually does and does not mean:
FDA approval means that, on average, the benefits of using a drug outweigh the risks in a well-defined set of patients with a specific disorder.
FDA approval means that the FDA has worked closely with the drug developer to create detailed prescribing information for the new drug
The prescribing information for every drug includes
Information about what types of patients the drug is approved for
Information about the effectiveness of the drug in this set of patients
Information about the side effects of the drug when used in this set of patients
Warnings about serious adverse effects (up to and including death) associated with the use of the drug
Information about the recommended dose of the drug and how it should be given to or taken by patients
FDA approval of a drug never implies that
A drug is completely safe
A drug has no side effects
All the side effects of a drug have been discovered
A drug will necessarily be effective for you as an individual
On average, the benefits of using a drug will outweigh the risks if the drug is used to treat an unapproved condition
A drug is “better” than other drugs for the approved condition (unless it has been compared to another drug or drug in a “head-to-head” clinical
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