PRE-MARKET FDA DRUG TESTING. IS THE DRUG REALLY SAFE? Under U.S. law, before a new drug can be marketed, it must be approved by our federal Food and Drug Administration (FDA). How then can a new drug earn approval and yet turn out so bad that it is subsequently withdrawn from the market?
PERHAPS THE ANSWER lies in the very nature of the approval process. Three phases of clinical trials in humans are conducted by the drug maker. In Phase I (1-2 yrs, on a small number of people), data are obtained on the basic safety of the new substance. In Phase II (2 yrs, on hundreds of people), estimates of effective dose and duration of treatment are made. In Phase 3 (1.5 yrs, thousands of people), effectiveness of treatment and possible side effects are discovered. If all goes well the New Drug Application (NDA) is FDA approved, the drug is given a generic and a trade name, and marketing begins.
HOWEVER, testing is not complete: essentially, ongoing trials are being conducted by the many thousands of patients who are now taking the drug.The FDA and the drug makers know and expect this. Reports of adverse effects - or worse - are made by doctors, nurses, and others, on special forms submitted to the FDA. As in the case of Vioxx and Bextra, the post-marketing discovery of severe adverse effects can result in product withdrawal.
SO WE ASK the question, could not the original clinical testing be expanded to discover serious effects. Realistically, we note that clinical trials can now take as long as 8-10 years and cost a claimed $800 million. The FDA-approval procees itself can take 2-3 yrs. Should that be expanded? Also, critics claim that the drug makers and the FDA are not always honest about adverse effects of their clinical testing, or down-play the results.
Another action can influence safety and efficacy of new drugs. Sometimes the FDA compromises its approval process by requiring a manufacturer to validate AFTER APPROVAL that the new drug works and is safe. That is, as the new drug is being used. This is supposed to be within a limited timeline, but in practice less than half of promised "proof" is not supplied as required. It must be said that after-approval testing can be very difficult. For example, if you were a cancer patient receiving this type of drug, would you possibly agree to receive a placebo during the after-approval testing, as required by the FDA?
CONCLUSION. At present, post-marketing use by large numbers of patients can reveal very serious adverse effects that the FDA process could not catch. Drug makers and the FDA must be acutely critical of data generated in the three phases of clinical trials. |