Actively Recruiting
A Phase 1 Randomised, Double-Blind, Placebo-Controlled Single Ascending Dose Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of CITY-FXI in Healthy Adults and Adults With Factor V Leiden or Prothrombin G20210A Mutation
Led by City Therapeutics · Updated on 2026-02-24
128
Participants Needed
1
Research Sites
8 weeks
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating the safety, tolerability, pharmacokinetics, and pharmacodynamics of CITY-FXI, a drug targeting Factor XI, in healthy adults and adults with Factor V Leiden (FVL) or prothrombin G20210A mutation. This first-in-human, randomized, double-blind, placebo-controlled study aims to better understand how CITY-FXI works in these populations and its potential effects. The trial is sponsored by City Therapeutics and includes participants aged 18 to 60 years. The study consists of two parts: Part A involves single ascending doses of CITY-FXI or placebo given by subcutaneous injection to healthy adults, and Part B includes similar dosing in adults diagnosed with FVL or prothrombin G20210A mutation. Women of childbearing potential in Part B must use highly effective contraception. The doses will be increased in a controlled manner to assess safety and drug behavior. Participants will be monitored for adverse events throughout the study, up to 360 days after dosing. Researchers will measure drug levels in the blood and urine shortly after dosing, and track changes in blood clotting factors and activity over time. Study visits will include physical exams, laboratory tests, and safety assessments to evaluate treatment effects and participant well-being over the follow-up period.
CONDITIONS
Brief Title
A Single Ascending Dose Study to Assess the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of CITY-FXI in Healthy Adults and Adults With FV Leiden or Prothrombin G20210A Mutation
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Males and women of non-childbearing potential aged 18 to 45 years (Part A only)
- Male and female participants aged 18 to 60 (Part B only)
- Body Mass Index (BMI) between 18 and 25 kg/m2 and minimum weight of 50 kg
- Ability and willingness to comply fully with all study procedures and lifestyle considerations
- Confirmed diagnosis of Factor V Leiden or prothrombin G20210A mutation via genetic testing (Part B only)
- Women of childbearing potential must agree to use acceptable highly effective contraceptive methods (Part B only)
You will not qualify if you...
- Any clinically significant systemic disease or disorder including cardiovascular, hepatic, or oncological conditions
- History or evidence of any bleeding disorders
- History of clinically significant spontaneous bleeding
- Prior treatment with an investigational agent
- Confirmed diagnosis of homozygous mutations or combined thrombophilic defects (Part B only)
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
Duration - Single dose with follow-up up to Day 360
Participants receive a single subcutaneous injection of CITY-FXI or placebo in either healthy adults or adults with Factor V Leiden or Prothrombin G20210A Mutation.
Multiple visits for assessments between Day -1 and Day 360
Trial Site Locations
Total: 1 location
1
Richmond Pharmacology
London, United Kingdom, SE1 1YR
Actively Recruiting
Research Team
C
City Therapeutics
How is the study designed?
Study Type
INTERVENTIONAL
Masking
DOUBLE
Allocation
RANDOMIZED
Model
SEQUENTIAL
Primary Purpose
TREATMENT
Number of Arms
4
Similar Trials
Frequently Asked Questions
Have more questions? Get in touch with our team for quick support
Not the Right Trial for You?
Explore thousands of other clinical trials that might be a better match.
Sign up to get personalized trial recommendations delivered to your inbox.
Already have an account? Log in here