PROJECT SUMMARY There is an enormous need for therapeutics to prevent and treat Alzheimer's disease (AD). Adult Hippocampal Neurogenesis (AHN) is critical for normal learning and memory, but it declines in patients with AD. Work in animal models has underscored the role of AHN in improving cognition in the face of AD pathology. Thus, restoring AHN has emerged as an attractive target for an AD therapy. Augmenting AHN in the diseased brain is widely considered a potential therapeutic modality for the treatment of AD as well as for other disease states characterized by diminished neurogenesis e.g., frontotemporal dementia, treatment-resistant depression, post traumatic stress disorder, and stroke. However, drug development efforts to date have lacked sufficient specificity to selectively increase AHN without perturbing other stem cell regulatory mechanisms. In this Phase I effort, Bolden Therapeutics will test exon-skipping antisense oligonucleotides (ASOs) against an undisclosed target expressed in neural stem cells to increase AHN. These candidate exon-skipping ASOs successfully skip the target region of interest in cultured cells and demonstrate favorable characteristics. We will use these ASOs in wild-type and AD mouse models to evaluate their effect on AHN, disease pathology, and cognition. Exon-skipping ASOs have emerged as effective and safe agents for regulating alternative splicing in the CNS. Determining in vivo efficacy of our candidate compounds is a critical step towards developing a highly targeted, safe and effective therapeutic for promoting AHN and improving cognition in AD. Following these studies, the exon-skipping ASOs will be ready for IND-enabling experiments and rapid preclinical development as we work towards developing a safe and effective therapy for AD and other disorders of impaired cognition via increasing AHN.