Alzheimer Disease, Amyloid beta-protein

Inclusion Criteria

- Presence of MCI defined as abnormal cognition on objective testing in the absence of dementia or significant functional loss.
 - Absence of systemic or other neurological disease that may contribute to cognitive impairment or prevent follow-up over two years.
 - Able to give written informed consent.
 - Age  >/= 60 years of age.

Exclusion Criteria

- Mini mental state examination (MMSE) score < 24 at baseline
 - Clinical dementia rating (CDR) score > 0.5 at baseline
 - Patients who receive regular medication of drugs which may adversely impact cognition (e.g. tricyclic antidepressants, antipsychotics and/or large doses of hypnotics or anxiolytics)
 - Existing or history of cancer
 - History of severe head trauma, brain surgery or intracranial hematoma with permanent brain lesion
 - Lifetime history of major affective disorder, schizophrenia, or schizo-affective disorder
 - Contraindications to MRI (Magnetic resonance imaging)
 - Relevant history, physical or imaging findings of neurological disease other than MCI and mild depression 
 - History of severe anaphylactic reaction or high risk of allergic reaction to drugs
 - Patient has received another investigational drug in the preceding 14 days