Anle138b ameliorates pathological phenotypes in mouse and cellular models of Huntington's disease

Huntington's disease (HD) is a hereditary movement disorder caused by a CAG repeat expansion in the huntingtin gene. HD is characterized by deposition of mutant huntingtin (mHTT) aggregates, and by severe neurodegeneration of the basal ganglia and neocortex. No cure is currently available, and new treatment options are urgently needed. Here, we show that the oligomer modifying molecule anle138b (INN: emrusolmin) improves multiple disease phenotypes in cell culture and in two mouse models of HD. Application of anle138b reduced mHTT aggregate formation and ameliorated neurotoxicity in primary neurons. Oral administration of anle138b delayed deposition of mHTT inclusions, reduced brain atrophy, mitigated neuroinflammation and transcriptional alterations, improved motor function and extended life span in HD mice. Downregulation of striatal markers and synapse loss in striatal spiny projection neurons were also partially rescued. No adverse effects of anle138b were observed in wildtype animals. Moreover, anle138b markedly decreased mHTT aggregation in human neural precursor cells differentiated from HD patient-derived induced pluripotent stem cells (iPSCs). Altogether these results illustrate the potential of anle138b as a disease-modifying treatment for HD.