AD is a neurodegenerative disorder characterized by severe memory loss and cognitive impairment with no available cure. Neuropathological correlates include extracellular amyloid-beta peptide deposition, intracellular neurofibrillary tangle formation, decreased synaptic integrity and neuronal loss. The basal forebrain cholinergic complex is significantly affected by AD-related neurodegeneration (59–63). To augment cholinergic function, Tuszynski and colleagues (64–68) delivered nerve growth factor (NGF), the prototypical neurotrophin with demonstrated neuroprotective properties, using retrovirus vector-transduced fibroblast grafts and demonstrated restoration and survival of cholinergic neurons in lesioned rodents and aged non-human primates. These initial studies set the stage for the first phase I clinical trial of ex vivo NGF gene therapy (ClinicalTrials.gov Identifier: NCT00017940). The rate of cognitive decline was slowed, and no apparent detrimental effects were observed arising from NGF expression 22 months post-engraftment (69). More recently, Ceregene has conducted phase I and II clinical trials using an AAV vector that expresses NGF (ClinicalTrials.gov Identifiers: NCT00087789 and NCT00876863, respectively). While the phase I trial demonstrated that stereotactic infusions of an NGF-expressing AAV vector is well tolerated, it is too early to know whether this gene therapy-based strategy will significantly impact the course and symptomology of the disease, given the phase II trial is currently ongoing.