An AE was any untoward, undesired, or unplanned clinical event in the form of signs, symptoms, disease, or laboratory or physiologic observations occurring in a person given study drug or in a sponsor's clinical study. The event did not need to be causally related to the study drug or the clinical studies. A treatment emergent AE was defined as an event that emerged during the treatment period that was absent before treatment, or worsened during the treatment period relative to the pretreatment state. An SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly.

Number of participants who experienced mild, moderate, or severe AEs (mild = does not interfere with subject's usual function; moderate = interferes to some extent with subject's usual function; severe = interferes significantly with subject's usual function)

Number of participants with brain abnormalities in MRI data that are either consistent or not consistent with AD, as determined by investigator.

Number of participants with abnormalities in neurological examinations as determined by the investigators. Neurological examinations included Mental Status, Speech, Cranial Nerves (including pupil equality and reactivity), Visual field, Sensory, Motor, Coordination, Gait, Primitive reflexes, Tendon reflexes and Romberg.