ACD855

ACD855 is a small molecule positive allosteric modulator (PAM) of the tropomyosin receptor kinases TrkA and TrkB, originally developed by AlzeCure Pharma for the treatment of cognitive and psychiatric disorders, including Alzheimer's disease and depression. The compound works by potentiating neurotrophin signaling, specifically involving nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), to enhance neuronal function and cognitive performance. Chemically, ACD855 is identical to the veterinary antiparasitic agent ponazuril. Although it demonstrated robust cognitive effects in preclinical models and was found to be safe in Phase I clinical trials, its development for systemic indications was terminated in 2019 due to an unexpectedly long half-life in humans. Following this termination, AlzeCure redirected the compound toward local administration for ocular indications, while its backup candidate, ACD856, became the primary lead for oral cognitive therapy.

Other names

ponazuril