Drug testing? 
Drug testing?
My guess is that if they could manufacture a liver, kidney, etc. they could test for drug toxicity and effectiveness w/o having to make use of humans for drug trials.
Drug trials are done in three phases: Phase I studies are usually just a test to see what a "safe" dosage of that particular drug is. It's a limited pool of patients, and they're not given any hope that the drug may cure them.
Think FDA drug approval, not DEA law enforcement.