Clinical trial Recruiting at 2 sites Phase 1 Interventional Ages 18 to 65

Testing CPTX2309 in healthy adults

Official title: A First-in-Human, Phase 1, Open-Label, Single and Multiple Ascending Dose Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of CPTX2309 by Intravenous Administration in Healthy Volunteers and Subjects With Moderate to Severe Rheumatoid Arthritis (RA) or Systemic Lupus Erythematosus (SLE)

Run by Capstan Therapeutics · NCT06917742 · Data updated 2026-11-12

This study is testing a new drug called CPTX2309 in healthy adults to see if it is safe and how their bodies react to it.

Quick facts

PhasePhase 1
Study typeInterventional
Ages18 Years to 65 Years
SexAll
Enrollment64 (estimated)
SponsorCapstan Therapeutics
Industry-sponsored
Locations3 sites (Herston, Queensland and 2 other locations)
StatusRecruiting
StartedApril 9, 2025
Main results expectedNovember 2027
Study endsNovember 2027
Registry record updatedJuly 16, 2026
Trial IDNCT06917742 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates for this study are healthy adult males and females who meet the inclusion criteria and are willing to comply with the study protocol.

Probably not a fit

Patients with any evidence of organ dysfunction or significant deviations from normal health may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This Phase 1 clinical trial aims to evaluate the safety and tolerability of CPTX2309 in healthy adult participants. The study involves administering a single ascending dose (SAD) and multiple ascending doses (MAD) of the drug intravenously. Participants will be closely monitored for any adverse effects or reactions to the treatment throughout the study duration. The trial is designed to gather essential data on how the drug behaves in a healthy population.

Why it matters

Potential benefit: If successful, this study could provide critical safety data that may support future clinical use of CPTX2309 in treating various conditions.

How similar studies have gone: While this is a first-in-human study, similar Phase 1 trials have successfully established safety profiles for new drugs in healthy volunteers.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Male and female participants who are healthy as determined by the investigator based on review of medical history, physical examination, and clinical laboratory tests obtained during the screening period.
* Participant is willing and able to adhere to the study visit schedule and other protocol requirements.

RA Only:

* Clinical diagnosis of RA and fulfilling the 2010 ACR/EULAR classification criteria for RA
* Presence of rheumatoid factor or ACPA above the ULN
* Confirmation of at least moderate active disease at screening with the presence of at least 6 swollen and 6 tender joints at screening using the 68 (tender)/66 (swollen) joint count OR the presence of at least 3 joints with active synovitis via MRI assessment.

SLE Only:

* Clinical diagnosis of SLE and fulfilling the 2019 EULAR/ACR classification criteria for SLE
* Positive ANA\>=1:80 and the presence of at least one of the following autoantibodies above the upper limit of normal (ULN): anti-double standard DNA (dsDNA) or anti-Smith (Sm).

Exclusion Criteria:

* Evidence of organ dysfunction or any clinically significant deviation from normal in physical examination, vital signs, or clinical laboratory tests beyond what is consistent with a healthy population in the region in which the study is conducted.
* Use of any investigational medical device or investigational drug within 30 days or 5 half-lives of the investigational drug (whichever is longer) prior to the first administration of CPTX2309.

RA Only:

\- Participants diagnosed with Felty's syndrome

SLE Only:

* Active neuropsychiatric SLE, as defined by the CNS portion of SLEDAI at Screening, or signs of symptoms of neuropsychiatric SLE within 6 months prior to Screening (lupus headache permissible)
* Note: Other protocol-defined inclusion/exclusion criteria apply

Where it's running

  • Veritus Research
    Bayswater, Victoria, Australia
    Recruiting
  • Linear Clinical Research
    Nedlands, Western Australia, Australia
    Recruiting
  • Nucleus Network Brisbane
    Herston, Queensland, Australia
    Completed

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.