Putting the cart before the horse
The typical course of drug R&D goes something like this:
- a druggable target is identified
- early discovery efforts are launched
- a lead drug candidate is selected
- preclinical studies are conducted
- an IND is filed
- PhI, PhII and PhIII trials are run in humans
Each of these steps requires successful completion of the previous ones for the sake of safety, efficient resource allocation and ultimately as a matter of due process. Paramount to drug R&D is safety, which is why drug candidates are first tested in animals and then, typically,