Read with caution!
This post was written during early stages of trying to understand a complex scientific problem, and we didn't get everything right. The original author no longer endorses the content of this post. It is being left online for historical reasons, but read at your own risk.
update 2013-01-31: this post has been deprecated; please see Fluphenazine, trimipramine and two styryl compounds for a more complete treatment of this subject.
@s just noticed today this study from late 2011. Thomas Wisniewski’s lab at NYU tested two already FDA-approved drugs, trimiprimine (an antidepressant) and fluphenazine (an antipsychotic) in mice and found significant delays (about 20%) in disease onset as well as reduction in severity. Since they’re both psychiatric-indicated drugs, they obviously both know how to cross the blood-brain barrier. The mouse model was scrapie mice infected via intraperitoneal injection.
The study in PLoS ONE:
And see also the NYU press release.