Not Yet RecruitingPhase 2

A Phase 2 Safety, Tolerability, PK, and Efficacy Study of CS-1103 Following Fentanyl Challenge With Naloxone Blockade

United States16 participantsStarted 2026-04

Plain-language summary

The purpose of the study is to evaluate the safety, tolerability, pharmacokinetics, and efficacy of CS-1103 (1,000 mg), given by intravenous (IV) infusion in healthy participants in the presence of a clinically relevant dose of fentanyl (200 μg, IV), with naloxone blockade (400 μg, IV).

Who can participate

Age range18 Years – 55 Years

SexALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion criteria

✓. Healthy participants aged 18 to 55 years, inclusive;
✓. Have prior experience with opioids, such as from a dental procedure, chronic pain management, or previous inpatient surgical procedure;
✓. A body mass index between 18.0 to 30.0 kg/m2, inclusive, and a minimum body weight of 56 kg;
✓. Females must not be lactating and must have a negative pregnancy test during screening and admission.

Exclusion criteria

✕. Estimated glomerular filtration rate \<60 mL/min/1.73 m2;
✕. History of cardiovascular disease;
✕. History of any clinically important disease or disorder which, in the opinion of the Investigator, may interfere with safe study participation.

What they're measuring

Number of participants with CS-1103-related adverse events (AEs) assessed by physical examinations

Timeframe: 3 days plus follow-up on Day 10

Number of participants with CS-1103-related adverse events (AEs) assessed by electrocardiograms (ECGs)

Timeframe: 3 days plus follow-up on Day 10

Number of participants with CS-1103-related adverse events (AEs) assessed by vital signs

Timeframe: 3 days plus follow-up on Day 10

Number of participants with CS-1103-related adverse events (AEs) assessed by laboratory parameters

Timeframe: 3 days plus follow-up on Day 10

Time course of CS-1103 blood and urine concentrations

Timeframe: 48 hours

Time course and magnitude of urine excretion of fentanyl

Timeframe: 48 hours

Trial details

NCT IDNCT07459166

SponsorClear Scientific, Inc.

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2026-07

Contact for this trial

Anna Del Rosario, B.S.

617-621-8500 adelrosario@clearsci.com

View on ClinicalTrials.gov More Fentanyl Overdose trials

Who can participate

Age range18 Years – 55 Years

SexALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion criteria

✓. Healthy participants aged 18 to 55 years, inclusive;
✓. Have prior experience with opioids, such as from a dental procedure, chronic pain management, or previous inpatient surgical procedure;
✓. A body mass index between 18.0 to 30.0 kg/m2, inclusive, and a minimum body weight of 56 kg;
✓. Females must not be lactating and must have a negative pregnancy test during screening and admission.

Exclusion criteria

✕. Estimated glomerular filtration rate \<60 mL/min/1.73 m2;
✕. History of cardiovascular disease;
✕. History of any clinically important disease or disorder which, in the opinion of the Investigator, may interfere with safe study participation.

What they're measuring

Number of participants with CS-1103-related adverse events (AEs) assessed by physical examinations

Timeframe: 3 days plus follow-up on Day 10

Number of participants with CS-1103-related adverse events (AEs) assessed by electrocardiograms (ECGs)

Timeframe: 3 days plus follow-up on Day 10

Number of participants with CS-1103-related adverse events (AEs) assessed by vital signs

Timeframe: 3 days plus follow-up on Day 10

Number of participants with CS-1103-related adverse events (AEs) assessed by laboratory parameters

Timeframe: 3 days plus follow-up on Day 10

Time course of CS-1103 blood and urine concentrations

Timeframe: 48 hours

Time course and magnitude of urine excretion of fentanyl

Timeframe: 48 hours