Generic drugs?

Question

How long does a prescription drug have to be on the market before they can make a generic version of it?

Answer 1

It's complicated.  The patent clock starts ticking once the drug is patented during drug discovery and trials.  In total, normally the drug is patented for about 20 years, and half of that time is before the drug is being sold.  However, there are a bunch of games the companies can play to try and extend the patent length.

Answer 2

The  short answer is 7-10 years, in the US.

The long answer is "it depends". Drug companies get patents for 20 years (in the US), but that is inclusive of the time they develop the drug and perform clinical trials. If it take a shorter/longer time to get the drug to market, they still only have a total of 20 years for the patent, so it could be more/less time until another company can apply for a generic.

Also, there are lots of loopholes that a drug company can slip into to extend their patent and prevent a generic access to the market. These processes can extend the patent for years.