According to a Yale School of Medicine study published in the January 22, 2014 issue of JAMA, reviewed 188 drugs and technologies from 2005-2012 and documented that more than 1/3 of the drugs were approved not only on the basis of a single clinical trial, but also were often small, short, and involved surrogate metrics rather than clear clinical endpoints. It is hard to have trust in these kinds of criteria.
The study also found that about 40% of drug approvals were brought to market without ever being compared to already existing approved drugs. The power of the FDA is remarkable, and makes one wonder if its conflicts of interest with the pharmaceutical and technology industries influence FDA approval.