(UroToday.com) The 2026 American Society of Clinical Oncology Genitourinary (ASCO) Annual Meeting held in Chicago, IL, will host the Kidney and Bladder Cancer - Posters Session. Dr. Muhammad H. Alkazemi presented Abstract 4623: Chemoablation with oral erdafitinib in recurrent FGFR3-altered NMIBC: A phase II window-of-opportunity trial.
Recurrence remains a major challenge in patients with NMIBC despite the availability of multiple intravesical therapies, often resulting in repeated TURBT procedures over time. Given the high prevalence of FGFR3 alterations in NMIBC, they evaluated the potential role of oral erdafitinib as a chemoablative strategy in patients with recurrent FGFR3-altered disease.
This window-of-opportunity trial enrolled patients with recurrent NMIBC harboring FGFR3 alterations identified through MSK-IMPACT testing. Patients received oral erdafitinib at a dose of 6 mg daily for approximately 28 days prior to TURBT. Tumor response was evaluated using RECIST-Bladder criteria, while tissue, blood, and urine samples were collected for pharmacodynamic and biomarker analyses. Adverse events were graded according to CTCAE v5.0.
A total of 20 patients with recurrent FGFR3-mutated NMIBC were enrolled. The most common FGFR3 alterations included S249C (n=12), followed by Y373C (n=3) and R248C (n=3). Most patients (70%) had a prior history of low-grade Ta disease. All patients had previously received at least one intravesical therapy, while 55% had undergone multiple prior courses of BCG, gemcitabine, mitomycin, or combination intravesical regimens.
Oral erdafitinib demonstrated encouraging activity in this recurrent NMIBC population, with an objective response rate of 75% (15/20). Complete response was achieved in 11 patients, corresponding to a CR rate of 55%.
Treatment was generally well tolerated, with no grade ≥3 toxicities observed during the study period.
Key remarks:
- Oral erdafitinib demonstrated promising chemoablative activity in recurrent FGFR3-altered NMIBC
- The study achieved an objective response rate of 75%, including complete responses in more than half of treated patients
- Most enrolled patients had heavily pretreated disease with prior exposure to multiple intravesical therapies
- Treatment was well tolerated, with no grade ≥3 toxicities observed
- These findings support further investigation of FGFR-targeted approaches in molecularly selected patients with NMIBC
Presented by: Muhammad H. Alkazemi, MD, Urologic Oncology Fellow at the Dept. of Surgery, Memorial Sloan Kettering Cancer Center, New York City, NY
Written by: Julian Chavarriaga, MD, Clinical Assistant Professor, Urologic Oncologist, Department of Urology at Penn State Health @chavarriagaj on X during the American Society of Clinical Oncology Genitourinary (ASCO) Annual Meeting held in Chicago, IL between May 29th and June 1st, 2026