The Food and Drug Administration (FDA) has been archiving the FDA.gov site at archive-it.org .
Leaving a lot of dead links on the FDA site. Sometimes they tell you to look in the archives for the old information, without giving you a link to it, and sometimes they don't, they just expect you to know.
Now why can't the FDA afford the space to keep their pages forever on their own site? Fill in your favorite conspiracy theory...
Some of the information that has been removed, such as the 2015 hearings on Fluoroquinolone antibiotics, are important health research as just one example.