Aren't there problems when something potentially useful wouldn't be patentable (say, it's already known elsewhere) so there's no major profit in going thru the

Aren't there problems when something potentially useful wouldn't be patentable (say, it's already known elsewhere) so there's no major profit in going thru the FDA approval process? I'd think it would be better to tie the temporary exclusivity to who put it thru the approval process directly (and relax the restrictions a bit, but that's a separate issue...).