A Randomized, Double-blind, Placebo-controlled, Parallel-group, Multicenter Study to Assess the Efficacy and Safety of JNJ-63733657, an Anti-tau Monoclonal Antibody, in Participants With Early Alzheimer’s Disease

– Early Alzheimer’s disease (AD): Gradual and progressive subjective decline in the
participant’s cognition over at least the past 6 months, as reported by the
participant and informant (study partner) and Clinical Dementia Rating-Global Score
(CDR-GS) of 0.5 and memory box score greater than or equal to (>=) 0.5

– Participants must have positive tau PET results

– Able to read and write and with a minimum 5 years of formal education as reported by
participant and study partner at screening

– Have a designated study partner who has adequate literacy to participate and be judged
to have high likelihood of completing the study with the participant

– Male participants must agree not to donate sperm during the study and up to 16 weeks
after the last dose of study intervention

Exclusion Criteria:

– Participants with CDR GS >=1 during screening or at predose baseline CDR
administration

– Participants who fulfill diagnostic criteria for Mild Cognitive Impairment (MCI) or
dementia/mild or major neurocognitive disorder suspected to be due to any etiology
other than AD (eg, MCI/dementia due to frontotemporal lobar degeneration, diffuse lewy
body disease, parkinson’s disease, cerebrovascular disease, normal pressure
hydrocephalus, head injury, drug or alcohol abuse/dependence, anoxic brain injury, (Et
cetera[etc])

– Geriatric Depression Scale (GDS) 30 score >=11

– Rosen Modified Hachinski Ischemic Scale (HIS) > 4

– Has received medications that affect the central nervous system (CNS), except
treatments for AD, for less than 2 months; that is, doses of chronic medications that
effect the CNS should be stable for at least 2 months before the start of screening