MDR-1339 (DWK-1339) is an orally active and blood-brain-barrier-permeable Aβ-aggregation inhibitor, used in the research of Alzheimer's disease. IC50 & Target: Amyloid-β^[1] In Vitro: MDR-1339 is an Aβ-aggregation inhibitor, and shows no significant inhibition a panel of CYP isozymes, while it slightly inhibits CYP2C8 (IC₅₀, 31.4 μM). MDR-1339 (3.1-50 μM) dose-dependently blocks the formation of Aβ aggregates, and disaggregates Aβ fibrils. MDR-1339 (1.5-10 μM) also protects cells from this Aβ-induced toxicity^[1]. In Vivo: MDR-1339 (0.1-10 mg/kg, p.o.) dose-dependently restores the passive avoidance responses in mice models of Alzheimer's disease (AD), with an ED₅₀ of 0.19 mg/kg. MDR-1339 (30 and 100 mg/kg, p.o. daily for 8 weeks) significantly improves spontaneous alternation, and reduces the Aβ_1-40 and Aβ_1-42 levels in APP/PS1 mice^[1].