CompletedPhase 1Results posted

A Safety Study of PTI-125 in Healthy Volunteers

A Phase I, Single Center, Randomized, Double-blind, Placebo-controlled, Single Ascending Dose, Pharmacokinetic and Safety Study of PTl-125 in Healthy Volunteers

Lead sponsor

Pain Therapeutics

Asset

Simufilam

Listed sites

Recruiting sites

Enrollment

actual

Study population

Alzheimer’s disease

Key I/E criterion

•Age 18-45

Primary endpoints

•Cmax•Cmax (Tmax) (Tmax)•Last Quantifiable Plasma Concentration (Tlast)

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

Nih1R44AG056166

NCT IDNCT03784300

Org study IDPTI-125-01

Timeline

Milestones

Study start2017-08-18actual

Primary completion2017-10-09actual

Study completion2018-03-27actual

Study first posted2018-12-21actual

Last update posted2021-05-10actual

Results first posted2021-05-10actual

Assets

Drug assets

Simufilam

Study populations

Who this study enrolls

Alzheimer’s disease

Eligibility

Who can enroll

Minimum age18 Years

Maximum age45 Years

SexAll

Healthy volunteersAccepted

Inclusion criteria

•Male or female subjects between 18 and 45 years of age, inclusive.

•The subject has a body mass index (BMI) within 18-30 kg/m2 (inclusive).

•The subject is in good health as determined by medical history and physical examination and clinical laboratory parameters.

•The subject is willing and able to speak, read, and understand English and provide written informed consent.

•The subject is a non-smoker for at least 12 months. If a former smoker, the reason for stopping must be evaluated.

•Females who are physically incapable of childbearing defined as postmenopausal, or surgically sterile (hysterectomy, bilateral tubal ligation, bilateral oophorectomy or an Essure procedure). Appropriate documentation (ex; medical record) of the surgical sterilization procedure to be obtained and held within the subject's study file.

•The subject must agree to comply with the drawing of blood samples for the PK assessments.

•The subject is willing and able to comply with all testing and requirements defined in the protocol.

•The subject is willing and able to remain at the study site unit for the duration of the confinement period and return for the outpatient visit

Exclusion criteria

•The subject has any relevant deviations from normal in physical examination, electrocardiogram (ECG), or clinical laboratory tests, as evaluated by the investigator.

•The subject has had a clinically significant illness within 30 days of Check-in.

•The subject has a history of significant neurological, hepatic, renal, endocrine, cardiovascular, gastrointestinal, pulmonary, or metabolic disease.

•The subject has used any prescription medication within 14 days of dosing or overthe- counter (OTC) medication within 48 h of dosing or intends to use any prescription medication or OTC medication during the study that may interfere with the evaluation of study medication.

•The subject has used alcohol, caffeine or xanthine-containing products 48 h before dosing or intends to use any of these products during the study.

•The subject has used grapefruit, grapefruit juice, or grapefruit-containing products days before dosing or intends to use any of these products during the study.

•The subject has a history of substance abuse or a positive ethanol breath test, urine cotinine, or urine drug screen at screening or at check-in. The subject has a positive serum hepatitis B surface antigen or positive HCV antibody test at the Screening Visit.

•The subject has a positive HIV test at the Screening Visit.

•Female subject is pregnant or breastfeeding.

•The subject has received an investigational drug within 30 days of Check-in.

•The subject has donated or lost a significant volume of blood (>450 mL) within 4 weeks prior to the study.

•The subject is unwilling to reside in the study unit for the duration of the study or to cooperate fully with the investigator or site personnel.

•The subject has an AST/ALT or total bilirubin greater than the ULN. One repeat test will be allowed.

Endpoints (22)

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

14 endpoints

Primary/protocol endpoint

Maximum Plasma Concentration (Cmax)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Primary/protocol endpoint

Time to Maximum Plasma Concentration (Tmax) (Tmax)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

time to event, event

Primary/protocol endpoint

Time to Last Quantifiable Plasma Concentration (Tlast)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

time to event, event

Primary/protocol endpoint

Last Quantifiable Plasma Concentration (Clast)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Primary/protocol endpoint

Termination Elimination Half-Life (T1/2)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Primary/protocol endpoint

Area Under the Curve (AUC)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Primary/protocol endpoint

Area Under the Curve to Infinity (AUCinf)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Primary/registry result

Maximum Plasma Concentration (Cmax)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Posted result

Group	Value (mean), ng/mL	Standard deviation
50 mg PTI-125n=6 Participants	315	96.6
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	550	146
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	1240	276
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result

Time to Maximum Plasma Concentration (Tmax) (Tmax)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

time to event, event

Posted result

Group	Value (mean), hours	Standard deviation
50 mg PTI-125n=6 Participants	1.56	0.69
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	1.08	0.48
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	1.28	0.57
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result

Time to Last Quantifiable Plasma Concentration (Tlast)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

time to event, event

Posted result

Group	Value (mean), hours	Standard deviation
50 mg PTI-125n=6 Participants	44.0	16.4
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	46.0	4.6
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	50.00	11.8
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result

Last Quantifiable Plasma Concentration (Clast)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Posted result

Group	Value (mean), ng/mL	Standard deviation
50 mg PTI-125n=6 Participants	1.04	0.495
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	0.795	0.294
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	0.806	0.292
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result

Termination Elimination Half-Life (T1/2)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Posted result

Group	Value (mean), hours	Standard deviation
50 mg PTI-125n=6 Participants	6.05	3.87
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	4.45	0.39
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	5.93	3.87
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result

Area Under the Curve (AUC)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Posted result

Group	Value (mean), h*ng/mL	Standard deviation
50 mg PTI-125n=6 Participants	2040	893
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	3130	1150
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	8130	1530
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result

Area Under the Curve to Infinity (AUCinf)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

concentration, descriptive

Posted result

Group	Value (mean), h*ng/mL	Standard deviation
50 mg PTI-125n=6 Participants	2180	897
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	3260	1150
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	8250	1530
200 mg PTI-125 Placebon=2 Participants	NA	NA

Other (unclassified)

8 endpoints

Primary/protocol endpoint/low confidence

Elimination Rate Constant (λz)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

descriptive

Primary/protocol endpoint/low confidence

Percent Extrapolated of Area Under the Curve to Infinity (AUCextrap[%]).

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

threshold achievement, improvement

Primary/protocol endpoint/low confidence

Oral Clearance (Cl/F)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

descriptive

Primary/protocol endpoint/low confidence

Volume of Distribution (Vz/F)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

descriptive

Primary/registry result/low confidence

Elimination Rate Constant (λz)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

descriptive

Posted result

Group	Value (mean), 1/hour	Standard deviation
50 mg PTI-125n=6 Participants	0.141	0.0539
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	0.157	0.0155
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	0.144	0.0516
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result/low confidence

Percent Extrapolated of Area Under the Curve to Infinity (AUCextrap[%]).

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

threshold achievement, improvement

Posted result

Group	Value (mean), percent extrapolated	Standard deviation
50 mg PTI-125n=6 Participants	0.410	0.187
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	0.151	0.0366
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	0.144	0.0156
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result/low confidence

Oral Clearance (Cl/F)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

descriptive

Posted result

Group	Value (mean), (L/h)	Standard deviation
50 mg PTI-125n=6 Participants	25.7	8.42
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	33.0	8.16
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	24.9	4.53
200 mg PTI-125 Placebon=2 Participants	NA	NA

Primary/registry result/low confidence

Volume of Distribution (Vz/F)

Time frame:Blood samples will be drawn on Day 1 after dosing at 20, 40, and 60 minutes and at 2, 3, 4, 6, 8, 12, 24, 36, 48 and 72 hours.

descriptive

Posted result

Group	Value (mean), (L)	Standard deviation
50 mg PTI-125n=6 Participants	199	64.9
50 mg PTI-125 Placebon=2 Participants	NA	NA
100 mg PTI-125n=6 Participants	215	64.8
100 mg PTI-125 Placebon=2 Participants	NA	NA
200 mg PTI-125n=6 Participants	214	154
200 mg PTI-125 Placebon=2 Participants	NA	NA

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.