AC-1204 26-Week Long Term Efficacy Response Trial With Optional Open-label Ext

Inclusion Criteria: * Dementia status of mild to moderate * CT or MRI scan within 18 months prior to screening compatible with a diagnosis of probable Alzheimer's disease * Score on the Wechsler Memory Scale - Logical Memory II recall below a pre-determined cut-off, adjusted for education level * Confirmed apolipoprotein E genotype prior to randomization * Prior and current use of medication that corresponds with protocol requirements * Stable medical condition, with the exception of dementia, for at least 3 consecutive months prior to screening * No active suicidal thoughts within 6 months of screening, no active history of suicide attempt in the previous 2 years, no more than 1 lifetime suicide attempt, no serious suicidal risk * Able to comply with protocol testing and procedures for the duration of the study * Has a permanent caregiver (caregiver is not expected to change during the course of the study) who is willing to attend all visits, oversee the participant's compliance with protocol procedures and study medication administration, and report on the participant's status * Resides in the community (includes assisted living facilities, but excludes long-term care nursing facilities) * Both participant and caregiver have the ability to read and write in English or Spanish and have hearing, vision and physical abilities adequate to perform the assessments (corrective aids allowed) * Participant and caregiver have provided full written informed consent prior to the performance of any protocol-specified procedure. If participant is unable to provide informed consent due to cognitive status, provision of informed consent by cognitively intact legally acceptable representative (where this is in accordance with local laws, regulations and ethics committee policy) * Participant is able to ingest oral medication Exclusion Criteria: * Current use, or use within 3 months of baseline, of medium-chain triglyceride-containing products * Use of any other investigational agent within 60 days prior to screening * Known allergy or hypersensitivity to milk or soy products * In the opinion of the investigator, presence or history of advanced, severe, progressive or unstable disease of any type that could interfere with protocol assessments or put the participant at particular risk * Any medical or neurological condition other than Alzheimer's disease that could explain the patient's dementia * History or clinical laboratory evidence of moderate congestive heart failure * Clinically significant ECG abnormalities at screening * History of new cardiovascular events within 6 months prior to baseline * History of or current psychiatric illness * Major depression as determined by Cornell Scale for Depression in Dementia * Insulin-dependent diabetics * Systolic blood pressure \> 165 mmHg or diastolic blood pressure \> 95 mmHg * Drop of 20 mm Hg systolic blood pressure or greater upon standing upright from a seated position within 3 minutes at screening * Clinically significant anemia at screening * Clinically significant renal disease or insufficiency at screening * Laboratory values for liver function tests \> 2.5 times the upper limit of normal at screening or history of severe liver disease * Fasting triglycerides \> 2.5 times the upper limit of normal at screening * Clinically significant B12 deficiency within 12 month prior to screening * Inflammatory bowel disease or peptic ulcer disease. * Participants with current or a history of (within the last 5 years) complicated reflux disease or severe GERD that is not well-controlled by medication. * Irritable bowel syndrome, diverticular disease (e.g., diverticulosis or diverticulitis), or chronic gastritis (exclusionary if there has been a diagnosis or an acute event within 5 years prior to Screening.) * Has donated ≥ 2 units of blood within the 2 months prior to screening * History of alcohol or drug abuse within 6 months prior to screening, or positive urine drug test at screening * Participant or caregiver is an immediate family member or employee of the clinical site, sponsor or sponsor's agents * An alternative cause for dementia other than Alzheimer's disease as determined by a required CT or MRI scan within 18 months prior to screening * History of neoplasm or malignancies within 5 years prior to screening, except for basal cell or squamous cell carcinoma of the skin * Clinically significant hypothyroidism as determined thyroid function testing at screening * Participant has scheduled or expected hospitalization and/or surgery during the course of the study