Safety and tolerability will be assessed through reporting of adverse events, physical and neurological testing, ECGs, as well as blood and urine analyses. Baseline and end-point measures of cognition and function, MRI brain scans, and cerebrospinal fluid (CSF) biomarker analyses will be used to determine preliminary efficacy of TPI-287 in mild-moderate AD. Pharmacokinetic and pharmacodynamic properties of TPI-287 will be calculated from blood plasma collected after the first infusion, and from CSF collected on the last visit of the placebo-controlled phase.