Authors: Martha Powell, Future Science Group
Prion diseases, also termed transmissible spongiform encephalopathies (TSEs), are a group of destructive neurodegenerative diseases, which at present lack any effective treatment and without this, are universally fatal [1,2].
Prion diseases result from the misfolding of cellular prion protein (PrPC) – a naturally occurring cell-surface protein – into a mutant, pathological and transmissible conformation (PrPSc). PrPSc can self-replicate by inducing the conformational transformation of PrPC; thus triggering fatal brain damage and other progressive symptoms such as personality changes and mobility restrictions [4,5].
Confirmed human prion diseases exist in three distinctive forms: sporadic (sporadic Creutzfeldt-Jakob disease (CJD)), genetic (genetic CJD) and acquired (kuru, variant CJD and iatrogenic CJD); sporadic is the most common form, accounting for 85% of incidences. TSEs are also exemplified in animals, for example, scrapie in sheep, bovine spongiform encephalopathy in cattle and chronic wasting disease in deer. Human prion diseases affect approximately one in a million individuals worldwide per annum and have become a serious concern since the emanation of the variant Creutzfeldt-Jakob disease (vCJD) – a zoonotic form of prion disease originating from the bovine spongiform encephalopathy agent [1,3].
Although there are currently no effective treatments, several compounds have been trialed in human studies thus far. Here, we take a look at the treatments that have been studied in humans –either in clinical trials, or on a compassionate, case-by-case basis – and look at what the future might hold for the treatment of prion diseases.