Actually the story of the FDA and thalidomide is worth knowing. The FDA delayed approval out of dumb luck in the late 1950's and early 1960's and the US missed all those awful birth defects (the kids born with flipper like limbs). The woman who called for more studies was later given a medal by President Kennedy. That led to a culture of cautiousness at the FDA for many decades and is a current that exists to this day. The push to get HIV drugs approved more quickly modified that somewhat in the 80's and 90's, but that cautiousness is still a major trait at the FDA, and has seen a resurgence after the all the issues with the COX-2 inhibitors.
If you are hoping to get a drug approved by the FDA, it is worth knowing the culture of the FDA.
Also if you look at websites devoted to claims of injury from vaccines, you will see a lot of concern about adjuvants, and I think that it is a reasonable conclusion that the FDA will be extra cautious about approving new adjuvants.
Hopefully, though, Ampligen's status as an orphan drug will help it get approved for CFS. If XMRV is out of the picture, they will still be an orphan drug and will not have competition from antiretrovirals for the CFS market. It complicates their plans for doing another Phase III using XMRV antibody status, but I think that HEB has shown themselves to be flexible enough to adapt to changing circumstances.