Anle138b is a novel oligomer modulator and an aggregation inhibitor, blocking the formation of pathological aggregates of prion protein (PrP(Sc)) and of α-synuclein (α-syn) with good oral bioavailability, blood-brain-barrier penetration and no detectable toxicity. Anle138b shows a new approach for disease-modifying therapy in neurodegenerative diseases such as prion and Parkinson’s disease.