–First-in-human trial evaluating safety, tolerability, and clinical activity of FX-909 in patients with advanced solid malignancies including advanced urothelial carcinoma–

CAMBRIDGE, MA, USA I January 26, 2024 I Flare Therapeutics Inc., a biotechnology company targeting transcription factors (TF) to discover precision medicines for cancer and other diseases, today announced a poster presentation outlining the Phase 1 clinical trial design of FX-909, a highly potent and selective inhibitor of PPARG, at the 2024 ASCO Genitourinary Cancers Symposium taking place from January 25-27, 2024 in San Francisco, CA.

“FlareTx has built a robust body of preclinical evidence that supports investigation of FX-909 in clinical trials in patients,” said Michael L. Meyers, M.D., Ph.D., Chief Medical Officer of Flare Therapeutics. “Results shown to date reveal that FX-909 eradicates tumors in urothelial cancer (UC) animal models at low oral doses. Our scientists have also leveraged high PPARG expression as a defining feature of luminal muscle-invasive UC (MIUC) to identify genetically defined populations and select the patients that may be more likely to benefit from a treatment like FX-909. In addition, we recently shared novel translational data correlating increased PPARG expression with an immunosuppressive tumor microenvironment (TME) and shorter real-world progression-free survival to anti-PD1 treatment.”

PPARG drives luminal cell identity and accounts for two-thirds of all advanced cases of UC. Targeting PPARG offers a novel approach to treating advanced UC that could pave the way to improved clinical outcomes in patients with a luminal subtype. Treatment of genetically defined UC xenografts with FX-909 has shown an 84% tumor growth inhibition at a dose expected to be equivalent to a 50 mg dose in humans – the starting dose in the Phase 1 clinical study.

FX-909-CLINPRO-1 (NCT05929235) is a first-in-human, multicenter, open-label Phase 1 study designed to assess the safety and tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary clinical activity of FX-909 given orally to patients with advanced solid malignancies. Exploratory objectives include the evaluation of patient selection biomarkers from tissue and blood samples and association with clinical outcomes. In the US, approximately 10 sites are planned for Phase 1A and 12-15 sites for Phase 1B.

“While advanced bladder cancer and MIUC remain lethal diseases, we are starting to see a real renaissance in providing new treatment options, thanks to increasing knowledge of the underlying molecular pathways involved,” said Gopa Iyer, Genitourinary Oncologist & Early Drug Development Specialist, Memorial Sloane Kettering Cancer Center. “FlareTx’s novel mechanism of action offers the possibility of a much needed second line option for patients who demonstrate disease progression following standard-of-care platinum chemotherapy, immune checkpoint inhibition, and/or ADC-based therapies.”

Details for the presentation are as follows:

Poster Title: A Phase 1, First-in-Human, Dose-Escalation and Expansion Study of FX-909 in Patients with Advanced Solid Malignancies, Including Advanced Urothelial Carcinoma
Abstract Number: TPS709
Presenter: Gopa Iyer MD, Memorial Sloane Kettering Cancer Center
Date, Time: Session B: Urothelial Carcinoma – Friday, January 26, 2024, 11:30 AM-1:00 PM PT; 5:45 PM-6:45 PM PT
Location: Moscone West Conference Center, San Francisco, California Posters, Exhibits, and Food Room

About FX-909
Flare Therapeutics’ lead investigational compound, FX-909, is a first-in-class, highly potent and selective small molecule that inhibits the transcription factor peroxisome proliferator-activated receptor gamma (PPARG) to treat patients with the luminal subtype of advanced urothelial carcinoma (UC) and potentially other solid tumors. Preclinical data for FX-909 has demonstrated robust anti-tumor activity, excellent PK/PD correlation, durable efficacy, and a favorable safety profile in mouse models of UC (PPARG-amp and RXRA-mut) at very low oral doses.

About the FX-909 Phase 1 Study
The ongoing Phase 1 study is a first-in-human, dose-escalation and -expansion study of FX-909 in patients with advanced solid malignancies, including advanced urothelial carcinoma. The study will evaluate 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).

About Advanced Urothelial Carcinoma (UC)
There are an estimated 725,549 people living with bladder cancer in the United States alone, making it the sixth most common cancer overall, and fourth most common among men (SEER – 2020). Each year, there are more than 83,000 new cases diagnosed among men and women, and about 25% of those cases are classified as muscle-invasive UC (DRG 2020). Treatment outcomes have remained poor with typical five-year survival rates of 8% in advanced metastatic disease (SEER – 2020). The transcription factor peroxisome proliferator-activated receptor gamma (PPARG) is associated with the luminal lineage subtype which represents approximately 65% of all advanced UC cases (Robertson, Cell 2017). Recurrent genetic alterations in PPARG are characteristic of this molecular subtype.

About Flare Therapeutics Inc.
Flare Therapeutics is a biotechnology company exclusively focused on drugging transcription factors (TFs) to fully unlock the therapeutic potential of this previously elusive target class. Flare Therapeutics’ integrated discovery engine converges rich genetic, biochemical, and chemical insights to reveal druggable pockets and identify small molecule ligands capable of modulating TFs of high therapeutic potential. Our proteomic and mass spectrometry platform is powered by a proprietary library of electrophilic compounds unique to Flare Therapeutics. The team has rapidly established an emerging pipeline of programs, highlighted by FX-909, a first-in-class investigational orally bioavailable small molecule inhibitor of PPARG, a master regulator of the luminal lineage in advanced urothelial cancer that has entered the clinic. For more information, please visit www.flaretx.com and follow us on LinkedIn.

SOURCE: Flare Therapeutics