Approved drugs with CNS demyelination side effect., page-4

[Most investigators agreed that extremely acute clioquinol intoxications associated with gastrointestinal and neurological symptoms reflected ingestion of clioquinol at amounts exceeding therapeutic doses: symptoms generally rapidly resolved when exposure ceased. (Malizia, Macchiarelli, Ambrosini, Smeriglio and Andreucci, 1979)]
"Neurobehavioral Toxicology: Neurological and Neuropsychological Perspectives ...
By Stanley Berent, James W. Albers"
It seems like we have known for a long time that symptoms can resolve in humans after MPAC overdose. One problem in those days in Japan was the drug was not identified as the problem and symptoms were often treated with more CQ.
I don't understand how the FDA do not accept this. In a clinical trial with close observation any indication of toxicity could be quickly acted on. OK PBT2 has more BBB penetration than CQ, but to date in humans it seems to be safer. Of course because of lack of info I am guessing what the toxicities were, but the CQ neurological toxicities were demyelination.