The Food and Drug Administration (FDA) is a United States federal agency that is responsible for the control and supervision of various food and medical products. Specifically in regards to drug safety, the FDA requires drugs go through an approval process which consists of five steps: discovery/concept, preclinical research, clinical research, FDA review, and FDA post-market safety monitoring.
For the purposes of this debate, increasing testing requirements means increasing the length and due-dillegence performed during each step as well as adding longer term testing on human subjects before the post-market safety monitoring step and potentially adding additional steps before the drug is launched in the open market.