A Study in Patients With Metastatic Castration-Resistant Prostate Cancer
A Phase 1, First-in-Human, Dose-Finding Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of FX-111 in Patients With Metastatic Castration-Resistant Prostate Cancer
- Metastatic Castration Resistant Prostate Cancer
- mCRPC
- mCRPC (Metastatic Castration-resistant Prostate Cancer)
- Prostatic Neoplasms
- Prostatic Neoplasms, Castration-Resistant
- mCRPC or Advanced/Metastatic Solid Tumors
- mCRPC, Metastatic Castration Resistant Prostate Cancer
- Neoplasms Prostate
At a glance
- Phase
- Phase 1
- Study type
- Interventional
- Sponsor
- Flare Therapeutics Inc.
- Enrolment target
- 60
- Started
- 1 July 2026
- Main results due
- 15 February 2028
- Study sites
- 10
- Registry updated
- 24 September 2026
Can you take part?
- Aged 18 years and over.
- Men only.
- You need the condition being studied — healthy volunteers are not accepted.
These are the headline rules only. Every study has a longer list, and whether you are eligible is decided by the research team at the site — never by this page.
Read the full eligibility criteria
Inclusion Criteria: * Confirmed adenocarcinoma of the prostate. * PSA levels ≥ 2 ng/mL at screening visit. * Progressing PSA, defined as two consecutive increases in the most recent PSA measurements taken at least 1 week apart. * Progressed on Androgen Deprivation Therapy (ADT) and at least one prior potent Androgen Receptor (AR) pathway inhibitor given in castration-sensitive prostate cancer setting or approved for castration-resistant prostate cancer (eg, apalutamide, darolutamide, abiraterone, enzalutamide). * Ongoing primary ADT with gonadotropin-releasing hormone agonist or antagonist in the absence of bilateral orchiectomy. * Acceptable physical functioning and laboratory measurements, per the study protocol. * Discontinued prior therapies within protocol-specified timeframes. * Commit to use of highly-effective contraception while on study and for 90 days after. * Willing and able to adhere to the study visit schedule and other protocol defined requirements. Exclusion Criteria: * Predominance of small cell carcinoma of the prostate/neuroendocrine prostate cancer in most recent tumor biopsy. * Participants with brain metastases that require ongoing treatment with radiation or high-dose steroids. * Not recovered from side effects of prior surgery or cancer treatments. * Evidence of active viral, bacterial, or fungal infection requiring treatment with antivirals, antibiotics, or anti-fungal medications. * Prior treatment with AR degraders and molecules with an AR ligand such as AR Regulated Induced Proximity Targeting Chimera (RIPTAC). * Blood clots ≤ 4 weeks prior to start of treatment. * Concurrent malignancy requiring treatment or history of prior malignancy active within 2 years prior to the first dose of study drug. Patients may be eligible if the malignancy is clinically stable or has been treated with curative intent. * Any evidence of severe or uncontrolled systemic diseases. * Any condition that, in the opinion of the Investigator, would interfere with evaluation of the investigational product or interpretation of the patient's safety or study results.
What this study is about
In the sponsor’s own words, from the registry.
The goal of this clinical trial is to find out if FX-111 is safe enough to permit further studies in adult male participants with metastatic castration-resistant prostate cancer (mCRPC). It will also study the drug's pharmacokinetics (how the body breaks down FX-111) and how well FX-111 treats mCRPC. The main questions it aims to answer are:
What are the side effects of FX-111?
Does FX-111 work to reduce or prevent progression of mCRPC?
The study doctor will oversee participants' treatment with FX-111 and ask about any side effects. Participants will take FX-111 every day by mouth and will have regular physical and laboratory examinations to check health and tumor status.
Study sites(10)
START Los Angeles
Los Angeles, California, United States
Recruiting
Massachusetts General Hospital
Boston, Massachusetts, United States
Not yet recruiting
Dana Farber Cancer Institute
Boston, Massachusetts, United States
Not yet recruiting
START Midwest
Grand Rapids, Michigan, United States
Recruiting
START New Jersey
East Brunswick, New Jersey, United States
Recruiting
START Carolinas
Myrtle Beach, South Carolina, United States
Recruiting
Tennessee Oncology
Nashville, Tennessee, United States
Not yet recruiting
START Dallas-Fort Worth
Fort Worth, Texas, United States
Recruiting
NEXT Houston
Houston, Texas, United States
Recruiting
NEXT Oncology
San Antonio, Texas, United States
Recruiting
Showing 10 of 10 sites. 7 of the 10 sites on this study are recruiting right now — a site can stop enrolling while the study as a whole is still open.
Source: ClinicalTrials.gov record NCT07719361. Trialion does not run this study, is not paid to refer anyone to it, and cannot enrol you. Eligibility is always decided by the research team at the site.
Not the right study?
Answer three questions and see the studies recruiting near you, in plain language.
Find a study for me