Flare Therapeutics’ lead asset, FX-909, is currently undergoing its Phase 1 study of a first-in-human, dose-escalation and expansion study in patients with advanced solid malignancies, including advanced urothelial carcinoma.

The study is evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics and clinical activity of FX-909. FX-909 will be given initially in a dose-escalation phase (Part A) to determine the recommended Phase 2 dose. FX-909 will be given initially orally once daily in 28-day cycles. Part B will be a monotherapy expansion phase to further evaluate the efficacy, safety, tolerability, pharmacokinetics, and pharmacodynamics of FX-909 in patients with locally advanced (unresectable) or metastatic urothelial carcinoma. Additional information on this clinical trial can be found on www.clinicaltrials.gov (NCT05929235).


What is FX-909?
FX-909 is a novel, first-in-class small molecule that inhibits the transcription factor peroxisome proliferator-activated receptor gamma (PPARG). Discovered and developed by Flare Therapeutics Inc., FX-909 is being tested in a clinical study in patients with advanced solid malignancies, including advanced urothelial carcinoma, also known as bladder cancer.
What exactly is PPARG?
PPARG is a type of protein known as a transcription factor, which plays a significant role in regulating gene expression and various biological processes in the body. It is a nuclear receptor that binds to specific DNA sequences and influences the expression of genes. It is believed that when PPARG gene expression is high, bladder cancer can result. FX-909, a PPARG inhibitor, is believed to inhibit this mode of tumor growth.
How does FX-909 work as a treatment for bladder cancer?
Treatments that target and inhibit transcription factors have been backbone therapies in cancer for decades. The transcription factor PPARG was found to be over-expressed and genetically altered in the luminal subtype of advanced urothelial cancer, highlighting its potential as a target for treatment. FX-909 inhibits cell growth and causes tumor regression in bladder cancer models, and Flare Therapeutics is studying the drug to evaluate its efficacy, safety, and tolerability for the treatment of patients with bladder cancer.
What are the key findings from the preclinical data on FX-909?
The preclinical data has shown that FX-909 is highly potent, demonstrating robust anti-tumor activity in animal models of bladder cancer at very low oral doses, while exhibiting a favorable tolerability. You can learn more from our press release issued at the 2023 AACR meeting.
What is the main goal of the FX-909 clinical study?
The primary goals of the clinical study are to evaluate the safety and tolerability of FX-909 in the treatment of patients with bladder cancer, as well as to determine the right dose level for patients.
Are you currently enrolling in the FX-909 clinical study?
Yes, we are currently enrolling patients in the study of FX-909.
How can I learn more about the clinical study and eligibility to participate?
To learn more about the FX-909 study, sponsored by Flare Therapeutics, and eligibility criteria for participation, please visit the official clinical study page at https://clinicaltrials.gov/study/NCT05929235.
Who can I contact at Flare Therapeutics for more information about FX-909 or the clinical study?
For further general inquiries, you can contact Flare Therapeutics at clinops@flaretx.com. You can also consult with your doctor.
How is the drug administered?
In the clinical study, FX-909 will be given initially orally once daily in 28-day cycles.
Have patients been treated with FX-909?
Yes, patients have been dosed in the Phase 1 first-dose cohort of the FX-909 study. For more information, please read our press release about the dosing of patients issued on October 19, 2023.
What is the anticipated timeline for the Phase 1 study of FX-909?
The Phase 1 study consists of two parts: (1) the dose escalation phase anticipated to complete enrollment in advanced solid malignancies by the end of 2024, and (2) the dose-expansion phase in genetically-defined advanced bladder cancer, which is projected to complete enrollment in late 2025/early 2026.
How can we stay updated on the progress of FX-909 and the clinical study?
Please refer to the Flare Therapeutics’ News section or clinicaltrials.gov for the latest updates on FX-909.


Compassionate use, also called expanded access, refers to a pathway in which patients with serious or immediately life-threatening diseases may gain access to an investigational therapy outside the context of participation in clinical trials. At this time, Flare Therapeutics does not have an expanded access program that allows patients to have access to our investigational products prior to FDA approval.


This links to an external website.