There are typically three pre-licensure phases to a clinical trial (and yes, I have participated in conducting them), when safety is assessed via animal data, and from small to larger groups of human subjects as described on the FDA website and summarized below. However, Phase IV, which continues to look at more rare side effects and adverse outcomes are not always conducted; however, when enough people worldwide have been exposed to the drug, these more rare complications come to light. This is not the first drug to have these serious complications come to light, only when many many people have had the drug-- e.g., remember Phen-Fen in weight control which became linked to valvular heart disease?
As for your comment that questioned why the surgeon used the drug if he realized it was linked to embolism.... Apparently he did not know of the link, but only in retrospect--as similar cases began to be reported in the literature as case studies did he come to this conclusion.
Having said that, I agree Pelley's reporting on this and other stories is not up to par.
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A bit of a primer on Phase I-IV Clinical Trials:
http://www.fda.gov/FDAC/features/2003/503_trial.html Done at hospitals and research centers around the country, clinical trials are conducted in phases. Phase 1 trials try to determine dosing, document how a drug is metabolized and excreted, and identify acute side effects. Usually, a small number of healthy volunteers (between 20 and 80) are used in Phase 1 trials.
Phase 2 trials include more participants (about 100-300) who have the disease or condition that the product potentially could treat. In Phase 2 trials, researchers seek to gather further safety data and preliminary evidence of the drug's beneficial effects (efficacy), and they develop and refine research methods for future trials with this drug. If the Phase 2 trials indicate that the drug may be effective--and the risks are considered acceptable, given the observed efficacy and the severity of the disease--the drug moves to Phase 3.
In Phase 3 trials, the drug is studied in a larger number of people with the disease (approximately 1,000-3,000). This phase further tests the product's effectiveness, monitors side effects, and, in some cases, compares the product's effects to a standard treatment, if one is already available. As more and more participants are tested over longer periods of time, the less common side effects are more likely to be revealed.
Sometimes, Phase 4 trials are conducted after a product is already approved and on the market to find out more about the treatment's long-term risks, benefits, and optimal use, or to test the product in different populations of people, such as children.