Not every drug designed by pharmaceutical companies makes it to the market; very few do. Only 9.6% of new drugs in development in the years 2006-2015 successfully made it to the market to be used by patients. That’s because there’s quite a process a drug needs to go through to make sure it’s not only effective for what it’s designed for, but that it’s not harmful.
After animal trials, that provide essential information on the effects of the drug on vital organs and how toxic the drug is at different doses, the drug progresses to testing in humans.

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