Phase 1 data support erda-iDRS as bladder-sparing strategy in FGFR-altered disease

In this video, Antoni Vilaseca Cabo, MD, discusses the final analysis of the first-in-human phase 1 trial of the erdafitinib intravesical drug-releasing system (erda-iDRS, TAR-210), a device designed to deliver sustained local concentrations of the pan-FGFR inhibitor erdafitinib directly into the bladder over 3-month treatment cycles in patients with FGFR-altered non–muscle invasive bladder cancer (NMIBC). He presented the findings at the 41st Annual Congress of the European Association of Urology in London, United Kingdom.¹

The trial enrolled 2 distinct cohorts. Cohort 1 comprised high-risk, BCG-experienced patients with recurrent disease who had undergone complete tumor resection prior to treatment—essentially an adjuvant setting. Despite a heavily pretreated population in which 50% had at least 4 prior recurrences, the 12-month recurrence-free survival rate reached 83%, with a median recurrence-free survival of 20.3 months. Cohort 3 enrolled intermediate-risk patients with recurrent low-grade disease and visible tumors at enrollment, evaluating the device in a chemoablative role. Here, 89% of patients achieved complete response at first or second evaluation, with a median response duration of 18 months.

Safety, the primary end point, was favorable. Treatment-related adverse events were predominantly low-grade urinary symptoms—hematuria and dysuria—with only 5% of patients experiencing grade 3 or higher events. Critically, pharmacokinetic data confirmed sustained erdafitinib concentrations in urine alongside plasma levels approximately 40 times lower than urine levels. This explains the absence of systemic toxicities such as hyperphosphatemia and retinal toxicity that have characterized oral erdafitinib use in metastatic urothelial carcinoma. The quarterly device exchange aligns with standard cystoscopic surveillance intervals, adding no additional visits.

Vilaseca Cabo characterizes these results as proof of concept for the local delivery approach, with phase 2 and 3 trials now underway.

REFERENCE

1. Final analysis of the phase 1 first-in-human study of erda-iDRS, an erdafitinib intravesical drug-releasing system, in patients with non–muscle-invasive bladder cancer harboring select FGFR alterations. Presented at: 41st Annual Congress of the European Association of Urology. March 13-16, 2026. London, United Kingdom. Abstract LBA008. https://urosource.uroweb.org/resource-centres/EAU26/269116/abstract