Study With Lu AF20513 in Patients With Mild Alzheimer's Disease (AD) or Mild Cognitive Impairment (MCI) Due to AD

Inclusion Criteria: * The patient has a diagnosis of AD or Mild Cognitive Impairment (MCI) due to AD. * The patient has evidence of an abnormal amyloid and tau status, consistent with AD, by means of a positive CSF test at screening * The patient is aged ≥50 and ≤85 years. If a woman, the patient must be post-menopausal. Exclusion Criteria: * The patient has participated in a clinical study where he/she has received passive or active anti-Aβ immunotherapy or other active immunisation for the treatment of AD. * The patient has, in the investigator's opinion, evidence and/or history (clinically or on MRI) of any clinically significant neurodegenerative disease, serious neurological disorder, other intracranial or systemic diseases or conditions resulting in a definite or probable diagnosis of Major or Mild Neuro-Cognitive disorder other than AD, per DSM-5® criteria. Other in- and exclusion criteria may apply