TerminatedPhase 3Results posted

An Extension To The B1451027 Protocol To Evaluate The Long Term Safety And Tolerability Of Dimebon In Patients With Alzheimer's Disease

An Open Label Extension To The B1451027 Protocol To Evaluate The Long Term Safety And Tolerability Of Dimebon (PF 01913539) In Patients With Alzheimer's Disease

Lead sponsor

Pfizer

Asset

Dimebon

Listed sites

105

Recruiting sites

Enrollment

649

actual

Study population

Alzheimer’s disease

Key I/E criterion

•Age ≥50

Primary endpoint

•Adverse Events (AEs)

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

Org study IDB1451029

NCT IDNCT00939783

Timeline

Milestones

Study first posted2009-07-15estimated

Study start2009-09 (month precision)

Primary completion2010-08actual (month precision)

Study completion2010-08actual (month precision)

Last update posted2012-11-14estimated

Results first posted2012-11-14estimated

Assets

Drug assets

Dimebon

Study populations

Who this study enrolls

Alzheimer’s disease

Eligibility

Who can enroll

Minimum age50 Years

SexAll

Healthy volunteersNot accepted

Inclusion criteria

•Completion of previous Phase 3 Dimebon study (B1451027)

Exclusion criteria

•Have any severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the patient inappropriate for entry into this study.

Endpoints (8)

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.

Coverage by outcome category

Safety / tolerability / PK

Other (unclassified)

Safety / tolerability / PK

6 endpoints

Primary/protocol endpoint

Percentage of Participants With Adverse Events (AEs)

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, event

Primary/registry result

Percentage of Participants With Adverse Events (AEs)

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, event

Posted result

Group	Value (number), Percentage of participants	Reported bounds
Dimebonn=648 Participants	73.1	-

Secondary/protocol endpoint

Percentage of Participants With Abnormal Clinically Significant Vital Signs

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, event

Secondary/protocol endpoint

Percentage of Participants With Clinically Significant Electrocardiogram (ECG) Findings

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, event

Secondary/registry result

Percentage of Participants With Abnormal Clinically Significant Vital Signs

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, event

Posted result

Group	Value (number), Percentage of participants	Reported bounds
DimebonSystolic BP (<90 mmHg) (n=646)n=646 Participants	1.1	-
Increase in systolic BP (>=30 mmHg) (n=642)n=646 Participants	11.5	-
Decrease in systolic BP (>=30 mmHg) (n=642)n=646 Participants	12.0	-
Diastolic BP (<50 mmHg) (n=646)n=646 Participants	2.0	-
Increase in diastolic BP (>=20 mmHg) (n=642)n=646 Participants	8.1	-
Decrease in diastolic BP (>=20 mmHg) (n=642)n=646 Participants	9.7	-
Heart rate (<40 bpm) (n=646)n=646 Participants	0.0	-
Heart rate (>120/>140 bpm) (n=646)n=646 Participants	0.0	-

Secondary/registry result

Percentage of Participants With Clinically Significant Electrocardiogram (ECG) Findings

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, event

Posted result

Group	Value (number), Percentage of participants	Reported bounds
DimebonPR int (>=300 msec) (n=608)n=646 Participants	0.3	-
Increase in PR int (>=25/50%) (n=605)n=646 Participants	0.3	-
Increase in QRS int (>=25/50%) (n=646)n=646 Participants	1.4	-
QTcF int (>450 to <=480 msec) (n=646)n=646 Participants	18.3	-
QTcF int (>480 to <=500 msec) (n=646)n=646 Participants	1.9	-
QTcF int (>500 msec) (n=646)n=646 Participants	0.3	-
Increase in QTcF int (>30 to <=60 msec) (n=646)n=646 Participants	8.0	-
Increase in QTcF int (>60 msec) (n=646)n=646 Participants	0.3	-

Other (unclassified)

2 endpoints

Secondary/protocol endpoint/low confidence

Percentage of Participants With Abnormal Clinically Significant Laboratory Values

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, improvement

Secondary/registry result/low confidence

Percentage of Participants With Abnormal Clinically Significant Laboratory Values

Time frame:Baseline up to Week 65 (end of treatment)

threshold achievement, improvement

Posted result

Group	Value (number), Percentage of participants	Reported bounds
DimebonHemoglobin (<0.8*LLN) (n=646)n=646 Participants	0.3	-
Red blood cell count (< 0.8*LLN) (n=646)n=646 Participants	0.5	-
Mean corpuscular volume (<0.9*LLN) (n=646)n=646 Participants	0.8	-
Mean corpuscular volume (>1.1*ULN) (n=646)n=646 Participants	0.2	-
Platelets (>1.75*ULN) (n=646)n=646 Participants	0.2	-
White blood cell count (<0.6*LLN) (n=646)n=646 Participants	0.2	-
White blood cell count (>1.5*ULN) (n=646)n=646 Participants	0.2	-
Lymphocytes (<0.8*LLN) (n=646)n=646 Participants	1.4	-
Lymphocytes (>1.2*ULN) (n=646)n=646 Participants	2.6	-
Total neutrophils (<0.8*LLN) (n=646)n=646 Participants	0.6	-
Total neutrophils (>1.2*ULN) (n=646)n=646 Participants	4.3	-
Eosinophils (>1.2*ULN) (n=646)n=646 Participants	1.4	-
Monocytes (>1.2*ULN) (n=646)n=646 Participants	1.5	-
Total bilirubin(>1.5*ULN) (n=646)n=646 Participants	0.3	-
Aspartate aminotransferase (>3.0*ULN) (n=645)n=646 Participants	0.5	-
Alanine aminotransferase (>3.0*ULN) (n=645)n=646 Participants	0.9	-
Alkaline phosphatase (>3.0*ULN) (n=646)n=646 Participants	0.2	-
Albumin (>1.2*ULN) (n=646)n=646 Participants	0.2	-
Blood urea nitrogen (>1.3*ULN) (n=646)n=646 Participants	1.4	-
Creatinine (>1.3*ULN) (n=646)n=646 Participants	1.4	-
Sodium (<0.95*LLN) (n=646)n=646 Participants	0.3	-
Sodium (>1.05*ULN) (n=646)n=646 Participants	0.9	-
Potassium (<0.9*LLN) (n=645)n=646 Participants	0.6	-
Potassium (>1.1*ULN) (n=645)n=646 Participants	0.5	-
Calcium (>1.1*ULN) (n=646)n=646 Participants	0.3	-
Magnesium (<0.9*LLN) (n=646)n=646 Participants	0.5	-
Magnesium (>1.1*ULN) (n=646)n=646 Participants	22.0	-
Phosphate (<0.8*LLN) (n=646)n=646 Participants	0.2	-
Phosphate (>1.2*ULN) (n=646)n=646 Participants	0.2	-
Bicarbonate (<0.9*LLN) (n=646)n=646 Participants	0.8	-
Bicarbonate (>1.1*ULN) (n=646)n=646 Participants	0.2	-
Glucose (>1.5*ULN) (n=646)n=646 Participants	17.6	-
Creatine kinase (>2.0*ULN) (n=646)n=646 Participants	2.5	-
Urine specific gravity (>1.030) (n=643)n=646 Participants	3.4	-
Urine pH (>8) (n=643)n=646 Participants	0.3	-
Urine glucose (>=1) (n=643)n=646 Participants	5.3	-
Urine ketones (>=1) (n=643)n=646 Participants	2.2	-
Urine protein (>=1) (n=643)n=646 Participants	3.3	-
Urine blood (>=1) (n=643)n=646 Participants	52.1	-
Urine leukocyte esterase (>=1) (n=643)n=646 Participants	29.4	-
Urine RBC (>=6) (n=518)n=646 Participants	18.1	-
Urine WBC (>=6) (n=562)n=646 Participants	34.3	-

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.