A Clinical Study to Evaluate the Safety of CS-1103 in Healthy Participants

A Phase 1a, Randomized, Double-Blind, Placebo-Controlled, Single Center Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of CS-1103 Following Single, Ascending Intravenous Dose Administration in Healthy Participants

The purpose of this Phase 1a study is to evaluate safety, tolerability, and pharmacokinetics (PK) of single, ascending doses of CS-1103, administered by intravenous (IV) infusion in healthy participants.

Study Overview

• Status: Completed
• Conditions: Substance Use Disorders; Methamphetamine Abuse; Methamphetamine Intoxication
• Intervention / Treatment: Drug: CS-1103; Drug: Sterile Saline

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Kansas
    • Overland Park, Kansas, United States, 66212
      • Dr. Vince Clinical Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Major Inclusion Criteria:

1. Healthy male and/or female participants aged 18 to 55 years, inclusive.
2. A body mass index between 18.0 to 30.0 kg/m2, inclusive, and a minimum body weight of 50 kg.
3. Females must be of nonchildbearing potential.

Major Exclusion Criteria:

1. Estimated glomerular filtration rate <90 mL/min/1.73 m2
2. Any clinically significant abnormalities in rhythm, conduction or morphology of the resting ECG, and any clinically important abnormalities in the 12-lead ECG
3. Current smokers, or those who have smoked or used nicotine products (including nicotine patches) within 1 month prior to dose administration.
4. History of alcohol abuse or excessive intake of alcohol

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cohort 1; 6 participants received a single dose of 2.7 mg/kg (2.5 mg/kg free acid) CS-1103 administered as solution for infusion by IV over 10 minutes. A diluted CS-1103 saline solution in an IV bag is used for drug administration.	Drug: CS-1103; CS-1103 for infusion
Experimental: Cohort 2; 6 participants received single dose of 8.0 mg/kg (7.5 mg/kg free acid) CS-1103 administered as solution for infusion by IV over 10 minutes. A diluted CS-1103 saline solution in an IV bag is used for drug administration.	Drug: CS-1103; CS-1103 for infusion
Experimental: Cohort 3; 6 participants received a single dose of 16.0 mg/kg (15.1 mg/kg free acid) CS-1103 administered as solution for infusion by IV over 10 minutes. A diluted CS-1103 saline solution in an IV bag is used for drug administration.	Drug: CS-1103; CS-1103 for infusion
Experimental: Cohort 4; 6 participants received a single dose of 19.0 mg/kg (17.9 mg/kg free acid) CS-1103 administered as solution for infusion by IV over 10 minutes. A diluted CS-1103 saline solution in an IV bag is used for drug administration.	Drug: CS-1103; CS-1103 for infusion
Placebo Comparator: Placebo; 2 participants for each cohort were administered with placebo. Total administered volume of saline matched administered volume for the corresponding CS-1103 solution in each cohort.	Drug: Sterile Saline; Sterile Saline for Injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Treatment-Emergent Adverse Events (AEs)	Treatment-emergent adverse events assessed through physical examinations, vital signs (blood pressure, pulse rate, respiratory rate, oxygen saturation, and body temperature), electrocardiograms (digital 12-lead electrocardiograms (ECGs). Any correlation between CS-1103 plasma concentrations and changes in QT intervals will be noted), and laboratory parameters (clinical chemistry, hematology, coagulation, and urinalysis).	3 days plus 8 days for follow-up
Number of Participants by Severity of AEs	Severity of AEs was classified as mild, moderate, or severe (increasing severity). A subject experiencing multiple occurrences of an adverse event in a particular category was counted, at most, once for that category for each treatment.	3 days plus 8 days for follow-up

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma Pharmacokinetic (PK) Parameter: Cmax	Maximum concentration, obtained directly from the observed concentration versus time data.	End-of-Infusion (EOI), 5, 10, 20, 30, 40 min, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 36, 48 hr
Plasma PK Parameter: Tmax	Time of maximum observed blood plasma concentration (Cmax) of CS-1103	End-of-Infusion (EOI), 5, 10, 20, 30, 40 min, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 36, 48 hr
Plasma PK Parameter: t1/2	Terminal Elimination Half-life of CS-1103	End-of-Infusion (EOI), 5, 10, 20, 30, 40 min, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 36, 48 hr
Plasma PK Parameter: CL	Systemic Clearance of CS-1103	End-of-Infusion (EOI), 5, 10, 20, 30, 40 min, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 36, 48 hr
Plasma PK Parameter: Vz	Volume of Distribution of CS-1103	End-of-Infusion (EOI), 5, 10, 20, 30, 40 min, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 36, 48 hr
Urine PK Parameter: Fe (0-last)	Cumulative fraction of dose excreted in urine during the pooled collection intervals. Due to inherent error in measuring CS-1103 recovered in urine, the calculated recovery may exceed 100% of the dose.	Time intervals from 0-24 hours after IV administration of CS-1103

Collaborators and Investigators

• Sponsor: Clear Scientific, Inc.
• Collaborators: National Institute on Drug Abuse (NIDA)

Study record dates

Study Major Dates

• Study Start (Actual): February 7, 2024
• Primary Completion (Actual): May 30, 2024
• Study Completion (Actual): June 6, 2024

Study Registration Dates

• First Submitted: March 5, 2024
• First Submitted That Met QC Criteria: March 12, 2024
• First Posted (Actual): March 19, 2024

Study Record Updates

• Last Update Posted (Actual): November 10, 2025
• Last Update Submitted That Met QC Criteria: October 28, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders
• Other Study ID Numbers: CS-1103-01; U01DA053054 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No