A Phase 2 Safety, Tolerability, PK, and Efficacy Study of CS-1103 Following Fentanyl Challenge Wi… (NCT07459166) | Clinical Trial Compass
RecruitingPhase 2
A Phase 2 Safety, Tolerability, PK, and Efficacy Study of CS-1103 Following Fentanyl Challenge With Naloxone Blockade
United States16 participantsStarted 2026-05
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 range
18 Years – 55 Years
Sex
ALL
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.
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Number of participants with CS-1103-related adverse events (AEs) assessed by physical examinations
Timeframe: 3 days plus follow-up on Day 10
2
Number of participants with CS-1103-related adverse events (AEs) assessed by electrocardiograms (ECGs)
Timeframe: 3 days plus follow-up on Day 10
3
Number of participants with CS-1103-related adverse events (AEs) assessed by vital signs
Timeframe: 3 days plus follow-up on Day 10
4
Number of participants with CS-1103-related adverse events (AEs) assessed by laboratory parameters
Timeframe: 3 days plus follow-up on Day 10
5
Time course of CS-1103 blood and urine concentrations
Timeframe: 48 hours
6
Time course and magnitude of urine excretion of fentanyl