What Does It Mean When a Drug Companies “exclusivity” Runs Out on a Drug?

Question by JDH.: What does it mean when a drug companies “exclusivity” runs out on a drug?
What does it mean when a drug companies “exclusivity” on a drug runs out? Does it mean that others can make generics? Or must they wait for the patent to expire?

I am wondering because my grandmother is taking Namenda for Alzheimer’s Disease and the “exclusivity” expires in October of 2008 (this year), but the patent doesn’t expire until 2010.

Can anyone explain this to me, please? thank you.
By “exclusivity” I mean what the FDA grants a drug company for a particular product.

Best answer:

Answer by JoeHavinFun
Under exclusivity other companies can manufacture the drug but have to pay a royalty.
Once the patent expires they no longer have to.

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