Abroad

CompletedPhase 2Results posted

Study to Assess Adverse Events, Change in Disease Activity and How Oral ABBV-552 Capsules Moves Through the Body of Participants Aged 50 to 90 Years With Mild Alzheimer's Disease

A Randomized, Double-blind, Placebo-controlled, Dose-finding Study to Evaluate the Safety, Efficacy, Pharmacokinetics and Pharmacodynamics of ABBV-552 in Participants With Mild Alzheimer's Disease

Lead sponsor

AbbVie

Asset

ABBV-552

Listed sites

Recruiting sites

Enrollment

263

actual

Study population

Alzheimer’s disease

Key I/E criteria

•Alzheimer's disease•CDR global 0.5•MMSE 20-26

Primary endpoint

•ADAS-Cog

Footprint

Where this trial recruits

Site locations as reported to ClinicalTrials.gov. Site count is not enrollment count; per-site enrollment is not available from source.

Identifiers

Registered as

Secondary ID2022-501918-55-00EU CTR

Org study IDM23-515

NCT IDNCT05771428

Timeline

Milestones

Study first posted2023-03-16actual

Study start2023-06-05actual

Primary completion2024-08-06actual

Study completion2024-09-12actual

Last update posted2025-10-15actual

Results first posted2025-10-15actual

Assets

Drug assets

ABBV-552

Study populations

Who this study enrolls

Alzheimer’s disease

Eligibility

Who can enroll

Minimum age50 Years

Maximum age90 Years

SexAll

Healthy volunteersNot accepted

Inclusion criteria

•Diagnosis of probable Alzheimer's disease according to the National Institute of Aging-Alzheimer's Association (NIA-AA) (2011) criteria.

•Mini-Mental State Examination (MMSE) score of 20 to 26, a Clinical Dementia Rating (CDR) global score of 0.5 or 1.0, with a CDR memory score of 0.5 or higher, and at least 1 CDR functional domain (community affairs, home and hobbies, or personal care) score of 0.5 or higher at Screening Visit 1

Exclusion criteria

- Clinically significant and/or unstable medical conditions or any other reason that the investigator determines would interfere with participation in this study (e.g., unlikely to adhere to the study or procedures, keep appointments, or is planning to relocate during the study) or would make the participant an unsuitable candidate to receive ABBV-552.

Endpoints (2)

What's being measured

Protocol endpoints and posted registry outcome measures, grouped into outcome categories. Composite endpoints show their component event types. Standard codes (LOINC, SNOMED CT) are shown where available.

Global cognition

2 endpoints

Primary/protocol endpoint

Change From Baseline in the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog 14) Score at Week 12

Time frame:Week 12

ADAS-Cog

change from baseline, improvement

Primary/registry result

Change From Baseline in the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog 14) Score at Week 12

Time frame:Week 12

ADAS-Cog

change from baseline, improvement

Posted result

Group	Value (least_squares_mean), score on a scale	Standard error
Placebon=58 Participants	-1.26	0.660
ABBV-552: 1 mgn=56 Participants	-1.28	0.668
ABBV-552: 5 mgn=58 Participants	-1.68	0.658
ABBV-552: 15 mgn=59 Participants	-1.01	0.655

LS Mean of Difference-0.0295% CI-1.87 - 1.83p0.9819Mixed-effect Model Repeated Measurement

LS Mean of Difference-0.4295% CI-2.25 - 1.42p0.6545Mixed-effect Model Repeated Measurement

LS Mean of Difference0.2595% CI-1.58 - 2.08p0.7860Mixed-effect Model Repeated Measurement

Provenance

Sources

Trial identity, design, statusClinicalTrials.gov API v2

Snapshot dateJuly 21, 2026

Endpoint classificationDelfa ADRD endpoint taxonomy

Results tableClinicalTrials.gov results section

Trial facts come from public ClinicalTrials.gov records. Endpoint categories are Delfa's classification of those records, not a ClinicalTrials.gov field. All figures reflect the July 21, 2026 snapshot.