The problem here Eric, is with the way drug approval is now done. First, the FDA is not and never has been in this business of picking one drug over another. Their entire focus is supposed to be “safe & effective.” Thus, if a drug proves through scientific study to not actually do what it is supposed to or to carry significant risk of unintended consequences or to actually be harmful in some way rather than beneficial, it is the business of the FDA to say “You can’t sell that here” – even if a drug has been on the market for a number of years. Scientific studies take time. Evidence can take years to accumulate.
It used to be that much of the study involved in testing a new drug for FDA approval had to be done before the drug was approved by the FDA. Now, because of the demand for drugs to treat AIDS, drugs under development for “critical” things like AIDS and cancer are fast tracked – put out for general consumption after only limited testing. In the past, those new drugs were still available in a more limited way as part of ongoing medical studies. The participants knew from the get go that they were participating in a study for a drug that might or might not work (and that they might or might not get – some people always get a placebo.) Under these new rules, those studies are done AFTER the drug goes to market. Essentially, if you take a new drug these days you are a human guinea pig.
Because of the way the pharmaceutical regulations are now written, it is not the least uncommon for a company to come up with something new (and thus still under the fast-track regs) and much more expensive to replace something that is either proving to be a drug that is going to be pulled by the FDA or one that is approaching the end of the gravy train. Drug companies achieve huge, HUGE profits the first few years a drug is on the market because no generics are allowed. As that time comes to an end the drug is no longer profitable, so something new is developed.
