Clinical trials of newer drugs are somewhat risky in humans, thanks to 3D Printing, the newer organ-on-a-chip have been introduced that can cut off the risk. This newer technology is used to produce micro organs called organoids, especially liver, heart and lung which can then be used to test the drugs before use in humans. The technology is further being improved at Wake Institute for Regenerative Medicine with aid from Wake Forest Baptist Medical Center.
Source: https://www.sciencedaily.com/releases/2017/10/171005121056.htm