I do think medicine is a special category because people need it, whereas if there is a 36 month gap between a novel's first printing and second, I (being the radical copyright reform advocate I consider myself) wouldn't think we need an exception to allow other publishers to publish it during that window, as with medicine.
I do think that at some point that window is long enough that the author and publisher lose any logical justification for keeping something unavailable while the rest of us subsidize their ability (via courts, laws, and police) to do so. After all, if we're paying for that stuff, what are we getting in return?
Maybe we should look at it differently. If there was no patenting, only way to create drugs will be know-how: just keep contents secret and there will be no copy-catting. But that's not allowed: they can't sell drugs without telling the public what's in them, and assuring that the content and the effects of it have been thoroughly tested.
I do think that at some point that window is long enough that the author and publisher lose any logical justification for keeping something unavailable while the rest of us subsidize their ability (via courts, laws, and police) to do so. After all, if we're paying for that stuff, what are we getting in return?