For at least ten years, I have avoided commenting about this drug — the CFS community at onetime was very divided over it. Ampligen is also know as rintatolimod and poly(I).poly(C12U).
Efficacy of rintatolimod in the treatment of chronic fatigue syndrome/ myalgic encephalomyelitis (cfs/me).  “Rintatolimod has achieved statistically significant improvements in primary endpoints in Phase II and Phase III double-blind, randomized, placebo-controlled clinical trials with a generally well tolerated safety profile and supported by open-label trials in the United States and Europe.”
- Comment: while this sounds nice, “statistically significant” could mean as little as 1% improvement, see next quote
- “the immune modulator rintatolimod improved some measures of exercise performance compared with placebo in 2 trials (low strength of evidence).” 
- A double-blind, placebo-controlled, randomized, clinical trial of the TLR-3 agonist rintatolimod in severe cases of chronic fatigue syndrome.  “The improvement observed represents approximately twice the minimum considered medically significant by regulatory agencies.” — so, barely any improvement!
- A controlled clinical trial with a specifically configured RNA drug, poly(I).poly(C12U), in chronic fatigue syndrome.  “After 24 weeks, patients receiving poly(I).poly(C12U) had higher scores for both global performance and perceived cognition than did patients receiving placebo.”
After 22 years, the best results has been “statistically significant” being just a little above the minimum needed to make a claim of improvement. No remissions reported. For this one, a major thumbs down!!!