TerminatedPhase 1Results posted

A Study of LY2599666 in Healthy Participants and Participants With Mild Cognitive Impairment or Alzheimer's Disease (AD)

Single-Dose and Multiple-Dose, Dose-Escalation Study With LY2599666 to Evaluate the Safety, Pharmacokinetics, and Tolerability in Healthy Subjects and Patients With Mild Cognitive Impairment Due to Alzheimer's Disease and Mild-to-Moderate Alzheimer's Disease

Lead sponsor

Eli Lilly and Company

Assets

LY2599666 / Solanezumab

Listed sites

Recruiting sites

Enrollment

actual

Study population

Alzheimer’s disease, MCI / preclinical Alzheimer’s

Key I/E criteria

•mild-to-moderate AD•Amyloid biomarker required (PET)•Study partner/caregiver required•Healthy volunteers•MRI contraindications excluded

Primary endpoint

•Serious Adverse Event (SAE) Considered by the Investigator to be Related

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 ID15491

Secondary IDI2L-MC-ALCAEli Lilly and Company

NCT IDNCT02614131

Timeline

Milestones

Study first posted2015-11-25estimated

Study start2015-12 (month precision)

Primary completion2016-12actual (month precision)

Study completion2016-12actual (month precision)

Results first posted2019-09-23actual

Last update posted2020-06-17actual

Assets

Drug assets

LY2599666 Solanezumab

Study populations

Who this study enrolls

Alzheimer’s diseaseMCI / preclinical Alzheimer’s

Eligibility

Who can enroll

Minimum age20 Years

SexAll

Healthy volunteersAccepted

Inclusion criteria

Healthy Participants Part A:

•Overtly healthy males or females as determined by medical history and physical examination

•Have a body mass index (BMI) between 18.0 and 32.0 kilograms per meter squared (kg/m²), inclusive

Participants With Mild Cognitive Impairment or Alzheimer's Disease (AD) [Part B and C]:

•Participants are at least 50 years old at screening

•Present with Mild Cognitive Impairment (MCI) due to Alzheimer's Disease (AD) or mild-to-moderate AD

•Have a caregiver/study informant who provides a separate written informed consent to participate

•Have adequate vision and hearing for neuropsychological testing in the opinion of the investigator

•Positive florbetapir scan

Exclusion criteria

All Participants

•Are currently enrolled in a clinical trial involving an investigational product or off-label use of a drug or device or are concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study

•Have known allergies to LY2599666, solanezumab, or any related compounds or components of the formulations, or have a history of significant atopy

•Have an abnormality in the 12-lead electrocardiogram (ECG) that, in the opinion of the investigator, increases the risks associated with participating in the study

•Have an abnormal blood pressure as determined by the investigator

•Have significant allergies to humanized monoclonal antibodies, diphenhydramine, epinephrine, or methylprednisone

•Require treatment with other monoclonal antibodies

Participants With Mild Cognitive Impairment or Alzheimer's Disease (AD) [Part B and C]

•Have medical or surgical conditions in which lumbar puncture and or/catheter insertion is contraindicated

•Have any contraindication for magnetic resonance imaging (MRI) studies, including claustrophobia, the presence of metal (ferromagnetic) implants, or a cardiac pacemaker that is not compatible with MRI

Participants With Mild Cognitive Impairment or Alzheimer's Disease (AD) [Part C]

•Have had lymphoma, leukemia, or any malignancy within the past 5 years except for basal cell or squamous epithelial carcinomas of the skin that have been resected with no evidence of metastatic disease for 3 years, cervical carcinoma in situ, or in situ prostate cancer with a normal prostate-specific antigen post treatment

Endpoints (14)

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

4 endpoints

Secondary/protocol endpoint

Plasma Amyloid Beta1-40 (Aβ1-40 ) Concentration Part A

Time frame:Day 1: Pre-dose and 2, 4, 8, 12, 24, 48, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part A)

concentration, descriptive

Secondary/protocol endpoint

Plasma Amyloid Beta (Aβ1-40 and Aβ1-42) Concentration Part B

Time frame:Day 85: Pre-dose, 2, 4, 8, 12, 24, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part B)

concentration, descriptive

Secondary/registry result

Plasma Amyloid Beta1-40 (Aβ1-40 ) Concentration Part A

Time frame:Day 1: Pre-dose and 2, 4, 8, 12, 24, 48, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part A)

concentration, descriptive

Posted result

Group	Value (geometric_mean), picograms per milliliter (pg/mL)	Geometric coefficient of variation
10 mg LY2599666 (Part A Cohort 1)n=8 Participants	18800	29
25 mg LY2599666 (Part A Cohort 2)n=8 Participants	36200	13
100 mg LY2599666 (Part A Cohort 3)n=8 Participants	49500	10
200 mg LY2599666 (Part A Cohort 4)n=8 Participants	67700	20

Secondary/registry result

Plasma Amyloid Beta (Aβ1-40 and Aβ1-42) Concentration Part B

Time frame:Day 85: Pre-dose, 2, 4, 8, 12, 24, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part B)

concentration, descriptive

Posted result

Group	Value (geometric_mean), pg/mL	Geometric coefficient of variation
25 mg LY2599666 (Part B Cohort 5)Aβ1-40n=4 Participants	51400	14
Aβ1-42n=4 Participants	5730	10

Safety / tolerability / PK

10 endpoints

Primary/protocol endpoint

Number of Participants With One or More Serious Adverse Event (SAE) Considered by the Investigator to be Related to Study Drug Administration

Time frame:Baseline through 4 weeks (Part A) or 16 weeks (Part B )

event count, event

Primary/registry result

Number of Participants With One or More Serious Adverse Event (SAE) Considered by the Investigator to be Related to Study Drug Administration

Time frame:Baseline through 4 weeks (Part A) or 16 weeks (Part B )

event count, event

Posted result

Group	Value (count_of_participants), Participants	Reported bounds
Placebo (Part A)n=11 Participants	0	-
10 mg LY2599666 (Part A Cohort 1)n=8 Participants	0	-
25 mg LY2599666 (Part A Cohort 2)n=8 Participants	0	-
100 mg LY2599666 (Part A Cohort 3)n=8 Participants	0	-
200 mg LY2599666 (Part A Cohort 4)n=8 Participants	0	-
Placebo (Part B)n=2 Participants	0	-
25 mg LY2599666 (Part B Cohort 5)n=5 Participants	0	-

Secondary/protocol endpoint

Pharmacokinetics (PK): Maximum Concentration (Cmax) of LY2599666 Part A

Time frame:Day 1: Pre-dose and 2, 4, 8, 12, 24, 48, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part A)

concentration, descriptive

Secondary/protocol endpoint

Pharmacokinetics (PK): Maximum Concentration (Cmax) of LY2599666 Part B

Time frame:Day 85: Pre-dose, 2, 4, 8, 12, 24, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part B)

concentration, descriptive

Secondary/protocol endpoint

Pharmacokinetics (PK): Area Under the Concentration Versus Time Curve From Zero to Infinity (AUC 0-∞) of LY2599666 Part A

Time frame:Day 1: Pre-dose and 2, 4, 8, 12, 24, 48, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part A)

concentration, descriptive

Secondary/protocol endpoint

Pharmacokinetics (PK): Area Under the Concentration Versus Time Curve From Zero to 168 Hours (AUC 0-168) of LY2599666 Part B

Time frame:Day 85: Pre-dose, 2, 4, 8, 12, 24, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 96, 120, 168 hours post-dose (Part B)

concentration, descriptive

Secondary/registry result

Pharmacokinetics (PK): Maximum Concentration (Cmax) of LY2599666 Part A

Time frame:Day 1: Pre-dose and 2, 4, 8, 12, 24, 48, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part A)

concentration, descriptive

Posted result

Group	Value (geometric_mean), nanograms per milliliter (ng/mL)	Geometric coefficient of variation
10 mg LY2599666 (Part A Cohort 1)n=8 Participants	NA	NA
25 mg LY2599666 (Part A Cohort 2)n=8 Participants	780	74
100 mg LY2599666 (Part A Cohort 3)n=8 Participants	5310	28
200 mg LY2599666 (Part A Cohort 4)n=8 Participants	9810	44

Secondary/registry result

Pharmacokinetics (PK): Maximum Concentration (Cmax) of LY2599666 Part B

Time frame:Day 85: Pre-dose, 2, 4, 8, 12, 24, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part B)

concentration, descriptive

Posted result

Group	Value (geometric_mean), ng/mL	Geometric coefficient of variation
25 mg LY2599666 (Part B Cohort 5)n=4 Participants	636	41

Secondary/registry result

Pharmacokinetics (PK): Area Under the Concentration Versus Time Curve From Zero to Infinity (AUC 0-∞) of LY2599666 Part A

Time frame:Day 1: Pre-dose and 2, 4, 8, 12, 24, 48, 72, 96, 120, 168, 216, 264, 336, 504, 672 hours post-dose (Part A)

concentration, descriptive

Posted result

Group	Value (geometric_mean), nanogramshour per milliliter (nghr/mL)	Geometric coefficient of variation
10 mg LY2599666 (Part A Cohort 1)n=8 Participants	NA	NA
25 mg LY2599666 (Part A Cohort 2)n=8 Participants	96200	30
100 mg LY2599666 (Part A Cohort 3)n=8 Participants	691000	20
200 mg LY2599666 (Part A Cohort 4)n=8 Participants	1590000	27

Secondary/registry result

Pharmacokinetics (PK): Area Under the Concentration Versus Time Curve From Zero to 168 Hours (AUC 0-168) of LY2599666 Part B

Time frame:Day 85: Pre-dose, 2, 4, 8, 12, 24, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 96, 120, 168 hours post-dose (Part B)

concentration, descriptive

Posted result

Group	Value (geometric_mean), ng*hr/mL	Geometric coefficient of variation
25 mg LY2599666 (Part B Cohort 5) Day 85n=4 Participants	76100	30

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.