Alzheimer's disease (AD) is a progressive, irreversible neurological disorder and is the most common cause of dementia in the elderly population. Clinical symptoms of the disease may begin with occasional forgetfulness such as misplacement of items, forgetting important dates or events, and may progress to noticeable memory loss, increased confusion and agitation, and eventually, loss of independence and non-responsiveness. The purpose of this study is to test how safe ABBV-1758 is, how well it works, how the body processes it and what effects it has on the body. ABBV-1758 is an investigational drug being developed for the treatment of Alzheimer's disease. This study is conducted in 3 stages. Stage A is a multiple ascending dose study with a 1 in 5 chance (4:1 randomization) that participants are assigned to receive placebo. Stage B is a dose expansion phase, also using 4:1 randomization for ABBV-1758 or placebo. Stage C enrolls Japanese and Chinese participants with the same randomization scheme. Approximately 210 participants will be enrolled at about 55 sites in the United States, China, and Japan. Participants will receive intravenous (IV) or subcutaneous (SC) doses of ABBV-1758 or placebo once every 4 weeks (Q4W) for 24 weeks and will be followed for additional 12 weeks in the Follow-up Period. Participants will have the option of participating in a 12-month, blinded Extension Period receiving ABBV-1758 or placebo based on amyloid PET results. There may be higher treatment burden for participants in this trial compared to their standard of care due to study procedures. Participants will attend regular visits during the study at a hospital or clinic. The safety of the treatment will be checked by medical assessments, blood tests, and completing questionnaires.
Age range
50 Years – 90 Years
Sex
ALL
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Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Percentage of Participants Experiencing Adverse Events (AEs)
Timeframe: Up to approximately 40 weeks
Percentage of Participants with Abnormal Change from Baseline in Clinical Laboratory Test Results
Timeframe: Up to approximately 40 weeks
Percentage of Participants With Amyloid-Related Imaging Abnormalities (ARIA)
Timeframe: Up to approximately 40 weeks
Percentage of Participants with Abnormal Change From Baseline in Vital Sign Measurements
Timeframe: Up to approximately 40 weeks
Percentage of Participants with Abnormal Change From Baseline in Electrocardiograms (ECGs) Parameters
Timeframe: Up to approximately 40 weeks
Percentage of Participants Experiencing Any Suicidal Ideation or Suicidal Behavior As Assessed by Columbia-Suicide Severity Rating Scale (C-SSRS)
Timeframe: Up to approximately 40 weeks
Stage A, B, and C: Change from Baseline in Brain Amyloid Load
Timeframe: Up to approximately 28 Weeks
Stage A and C: Maximum Plasma Concentration (Cmax) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Time to Cmax (Tmax) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Trough Concentration measured at the end of a dosing interval at steady state (Ctrough) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Area under the Plasma Concentration-time Curve from Time Zero to the End of the Dosing Interval (AUCtau) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Average Serum Concentration at Steady-State (Cav,ss) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Accumulation ratio for (AUCtau) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Total Body Clearance (CL) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Apparent Clearance (CL/F) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Volume of Distribution at Steady-State (Vss)
Timeframe: Up to approximately 40 weeks
Stage A and C: Apparent Volume of Distribution during the Terminal Phase (Vz)
Timeframe: Up to approximately 40 weeks
Stage A and C: Terminal Phase Elimination Rate Constant (β) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Terminal Phase Elimination Half-Life (t1/2) of ABBV-1758
Timeframe: Up to approximately 40 weeks
Stage A and C: Effective Half-Life (T1/2,eff)
Timeframe: Up to approximately 40 weeks