TerminatedPhase 2Results posted

A Long-term Extension Study to Evaluate Safety, Tolerability, and Efficacy of AL002 in Alzheimer's Disease

A Multicenter, Long-term Extension Study to Evaluate the Safety, Tolerability, and Efficacy of AL002 in Participants With Alzheimer's Disease

Lead sponsor

Alector Inc.

Asset

AL002

Listed sites

Recruiting sites

Enrollment

197

actual

Study population

Alzheimer’s disease

Key I/E criterion

•Study partner/caregiver required

Primary endpoints

•Safety and Tolerability•Long-term Safety and Tolerability of AL002•Effect of Dose Titration on the Occurrence of ARIA-E by Assessing the Number

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 IDAL002-LTE

NCT IDNCT05744401

Timeline

Milestones

Study start2023-01-04actual

Study first posted2023-02-27actual

Primary completion2025-01-31actual

Study completion2025-02-05actual

Last update posted2026-02-25actual

Results first posted2026-02-25actual

Assets

Drug assets

AL002

Study populations

Who this study enrolls

Alzheimer’s disease

Eligibility

Who can enroll

Minimum age50 Years

Maximum age85 Years

SexAll

Healthy volunteersNot accepted

Inclusion criteria

•Completion of the Planned Treatment Period in the AL002-2 study.

•The participant is willing and able to give informed consent.

•Study partner who consents to study participation and who cares for/visits the participant at least 10 hours a week

Exclusion criteria

•Participants deemed not able to provide consent or assent by the Investigator or by local regulations.

•Participants who were prematurely and permanently discontinued from treatment in the parent study for safety reasons.

•Participation deemed inappropriate per Investigator discretion.

Endpoints (12)

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

Amyloid biomarkers

Behavior / neuropsychiatric

2 endpoints

Primary/protocol endpoint

To Evaluate the Long-term Safety and Tolerability of AL002, by Assessing the Number of Suicidal Risk Events Using the Columbia-Suicide Severity Rating Scale (C-SSRS)

Time frame:From the Screening period and throughout the treatment period until the end of the study participation up to 49 weeks.

event count, event

Primary/registry result

To Evaluate the Long-term Safety and Tolerability of AL002, by Assessing the Number of Suicidal Risk Events Using the Columbia-Suicide Severity Rating Scale (C-SSRS)

Time frame:From the Screening period and throughout the treatment period until the end of the study participation up to 49 weeks.

event count, event

Posted result

Group	Value (number), Number of Participants	Reported bounds
AL002 15 mg/kgn=41 Participants	1	-
AL002 40 mg/kgn=49 Participants	0	-
AL002 60 mg/kgn=43 Participants	0	-
Titration Cohortn=64 Participants	0	-

Amyloid biomarkers

4 endpoints

Primary/protocol endpoint

To Evaluate the Effect of Dose Titration on the Occurrence of ARIA-E by Assessing the Number of Participants With ARIA-E Events

Time frame:Screening, Week 9, Week 17, Week 25, Week 33, Week 41, End of Study visit, and Early Termination visit, if applicable up to 49 weeks

event count, event

Primary/protocol endpoint

To Evaluate the Effect of Dose Titration on the Occurrence of ARIA-H by Assessing the Number of Participants With ARIA-H Events

Time frame:Screening, Week 9, Week 17, Week 25, Week 33, Week 41, End of Study visit, and Early Termination visit, if applicable up to 49 weeks

event count, event

Primary/registry result

To Evaluate the Effect of Dose Titration on the Occurrence of ARIA-E by Assessing the Number of Participants With ARIA-E Events

Time frame:Screening, Week 9, Week 17, Week 25, Week 33, Week 41, End of Study visit, and Early Termination visit, if applicable up to 49 weeks

event count, event

Posted result

Group	Value (number), Number of Participants	Reported bounds
AL002 15 mg/kgn=97 Participants	23	-
AL002 40 mg/kgn=94 Participants	23	-
AL002 60 mg/kgn=77 Participants	17	-
Titration Cohortn=64 Participants	7	-

Primary/registry result

To Evaluate the Effect of Dose Titration on the Occurrence of ARIA-H by Assessing the Number of Participants With ARIA-H Events

Time frame:Screening, Week 9, Week 17, Week 25, Week 33, Week 41, End of Study visit, and Early Termination visit, if applicable up to 49 weeks

event count, event

Posted result

Group	Value (number), Number of Participants	Reported bounds
AL002 15 mg/kgIncidence of ARIA-Hn=97 Participants	30	-
Incidence of Microhemorrhagesn=97 Participants	17	-
Incidence of Superficial Siderosisn=97 Participants	12	-
Incidence of Macrohemorrhagesn=97 Participants	1	-
AL002 40 mg/kgIncidence of ARIA-Hn=94 Participants	30	-
Incidence of Microhemorrhagesn=94 Participants	18	-
Incidence of Superficial Siderosisn=94 Participants	12	-
Incidence of Macrohemorrhagesn=94 Participants	0	-
AL002 60 mg/kgIncidence of ARIA-Hn=77 Participants	25	-
Incidence of Microhemorrhagesn=77 Participants	18	-
Incidence of Superficial Siderosisn=77 Participants	6	-
Incidence of Macrohemorrhagesn=77 Participants	1	-
Titration CohortIncidence of ARIA-Hn=64 Participants	9	-
Incidence of Microhemorrhagesn=64 Participants	6	-
Incidence of Superficial Siderosisn=64 Participants	2	-
Incidence of Macrohemorrhagesn=64 Participants	1	-

Safety / tolerability / PK

6 endpoints

Primary/protocol endpoint

Safety and Tolerability as Measured by Number of Treatment-expected Adverse Events (TEAE) and Treatment-related Adverse Events (AEs).

Time frame:From the Screening period and throughout the treatment period until the end of study participation, up to 49 weeks.

event count, event

Primary/protocol endpoint

Safety and Tolerability as Measured by Number of Adverse Events of Special Interest and Serious Adverse Events

Time frame:From the Screening period and throughout the treatment period until the end of study participation, up to 49 weeks.

event count, event

Primary/protocol endpoint

Safety and Tolerability as Measured by the Number of Cases of Abnormal Vital Signs, Clinical Laboratory Results and Findings From Physical, Neurological, Ophthalmological Examinations and Electrocardiograms.

Time frame:From the Screening period and throughout the treatment period until the end of study completion, up to 49 weeks

event count, event

Primary/registry result

Safety and Tolerability as Measured by Number of Treatment-expected Adverse Events (TEAE) and Treatment-related Adverse Events (AEs).

Time frame:From the Screening period and throughout the treatment period until the end of study participation, up to 49 weeks.

event count, event

Posted result

Group	Value (number), Occurrence of Adverse Event	Reported bounds
AL002 15 mg/kgTEAE: Deathn=41 Participants	0	-
TEAE: Severen=41 Participants	1	-
TEAE: Moderaten=41 Participants	5	-
TEAE: Mildn=41 Participants	10	-
Treatment-Related TEAE: Deathn=41 Participants	0	-
Treatment-Related TEAE: Severen=41 Participants	1	-
Treatment-Related TEAE: Moderaten=41 Participants	2	-
Treatment-Related TEAE: Mildn=41 Participants	1	-
AL002 40 mg/kgTEAE: Deathn=49 Participants	0	-
TEAE: Severen=49 Participants	0	-
TEAE: Moderaten=49 Participants	3	-
TEAE: Mildn=49 Participants	17	-
Treatment-Related TEAE: Deathn=49 Participants	0	-
Treatment-Related TEAE: Severen=49 Participants	0	-
Treatment-Related TEAE: Moderaten=49 Participants	1	-
Treatment-Related TEAE: Mildn=49 Participants	4	-
AL002 60 mg/kgTEAE: Deathn=43 Participants	1	-
TEAE: Severen=43 Participants	2	-
TEAE: Moderaten=43 Participants	11	-
TEAE: Mildn=43 Participants	19	-
Treatment-Related TEAE: Deathn=43 Participants	0	-
Treatment-Related TEAE: Severen=43 Participants	0	-
Treatment-Related TEAE: Moderaten=43 Participants	2	-
Treatment-Related TEAE: Mildn=43 Participants	7	-
Titration CohortTEAE: Deathn=64 Participants	0	-
TEAE: Severen=64 Participants	4	-
TEAE: Moderaten=64 Participants	11	-
TEAE: Mildn=64 Participants	21	-
Treatment-Related TEAE: Deathn=64 Participants	0	-
Treatment-Related TEAE: Severen=64 Participants	2	-
Treatment-Related TEAE: Moderaten=64 Participants	4	-
Treatment-Related TEAE: Mildn=64 Participants	10	-

Primary/registry result

Safety and Tolerability as Measured by Number of Adverse Events of Special Interest and Serious Adverse Events

Time frame:From the Screening period and throughout the treatment period until the end of study participation, up to 49 weeks.

event count, event

Posted result

Group	Value (number), Occurrence of Adverse Event	Reported bounds
AL002 15 mg/kgTreatment-Emergent Adverse Event of Special Interestn=41 Participants	2	-
Treatment-Related Adverse Events of Special Interestn=41 Participants	2	-
Treatment-Emergent Serious Adverse Event (TESAE)n=41 Participants	0	-
Treatment-Related Serious Adverse Eventn=41 Participants	0	-
AL002 40 mg/kgTreatment-Emergent Adverse Event of Special Interestn=49 Participants	2	-
Treatment-Related Adverse Events of Special Interestn=49 Participants	2	-
Treatment-Emergent Serious Adverse Event (TESAE)n=49 Participants	0	-
Treatment-Related Serious Adverse Eventn=49 Participants	0	-
AL002 60 mg/kgTreatment-Emergent Adverse Event of Special Interestn=43 Participants	5	-
Treatment-Related Adverse Events of Special Interestn=43 Participants	5	-
Treatment-Emergent Serious Adverse Event (TESAE)n=43 Participants	3	-
Treatment-Related Serious Adverse Eventn=43 Participants	0	-
Titration CohortTreatment-Emergent Adverse Event of Special Interestn=64 Participants	11	-
Treatment-Related Adverse Events of Special Interestn=64 Participants	11	-
Treatment-Emergent Serious Adverse Event (TESAE)n=64 Participants	7	-
Treatment-Related Serious Adverse Eventn=64 Participants	3	-

Primary/registry result

Time frame:From the Screening period and throughout the treatment period until the end of study completion, up to 49 weeks

event count, event

Posted result

Group	Value (number), Occurrence of Abnormal Findings	Reported bounds
AL002 15 mg/kgn=41 Participants	0	-
AL002 40 mg/kgn=49 Participants	0	-
AL002 60 mg/kgn=43 Participants	0	-
Titration Cohortn=64 Participants	0	-

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.