Emerging drugs for progressive supranuclear palsy.

: Progressive supranuclear palsy (PSP) is a common cause of atypical parkinsonism and a rapidly progressive disease that greatly burdens both patients and caregivers. Drugs with disease-modifying potential, targeting mechanisms implicated in the disease's pathogenesis are currently tested in Phase 1 and 2 trials. If proven efficacious, these compounds might provide substantial benefits not only to patients with PSP but to patients with other tauopathies as well. : Drugs in Phase 1 and 2 trials in PSP, and Phase 2 trials in other tauopathies (Alzheimer's disease) are reviewed. : The rationale behind the currently tested compounds as well as the tools available to document a treatment effect offer hope for a therapeutic breakthrough in PSP. The current lack of sufficiently validated biomarkers remains a hurdle that needs to be overcome, in order to facilitate both clinical trials and the accurate prescription of future treatments.