AF710B, an M1/sigma-1 receptor agonist with long-lasting disease-modifying properties in a transgenic rat model of Alzheimer's disease

Introduction: AF710B (aka ANAVEX 3-71) is a novel selective allosteric M1 muscarinic and sigma-1 receptor agonist. In 3XTg-AD mice, AF710B attenuates cognitive deficits and decreases Alzheimer-like hallmarks. We now report on the long-lasting disease-modifying properties of AF710B in McGill-R-Thy1-APP transgenic (Tg) rats. Methods: Chronic treatment with AF710B (10 mu g/kg) was initiated in postplaque 13-month-old Tg rats. Drug or vehicle was administered orally daily for 4.5 months and interrupted 5 weeks before behavioral testing. Results: AF710B long-term treatment reverted the cognitive deficits associated with advanced Alzheimer-like amyloid neuropathology in Tg rats. These effects were accompanied by reductions in amyloid pathology and markers of neuroinflammation and increases in amyloid cerebrospinal fluid clearance and levels of a synaptic marker. Importantly, these effects were maintained following a 5-week interruption of the treatment. Discussion: With M1/sigma-1 activity and long-lasting disease-modifying properties at low dose, AF710B is a promising novel therapeutic agent for treating Alzheimer's disease. (C) 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.