Reducing the drug discovery and validation phase

Well, today I attended a lecture that talked about the drug discovery process. What boggled me, so much, was the amount of time and money wasted in order to clinically test and develop drugs. its mind BOGGLING! I don't understand how a better way to develop these drugs hasn't been uncovered!

Problems associated with phases

• target validation: finding the right target, how do you know whether it is the right one?
• toxicology: in the body, metabolism, 
• animal models: differs from humans, not an entirely accurate projection
• long-term effect: it takes time! 

I still don't understand why it takes away a lot of our resources... gonna research and update this post