TAR-210, an intravesical formulation of erdafitinib, is under investigation in a phase 1 study (NCT05316155) for patients with FGFR-altered high- and intermediate-risk non-muscle invasive bladder cancer (NMIBC). Antoni Vilaseca Cabo, MD, from Hospital Clínic de Barcelona, discussed the rationale and design of the study, highlighting the unmet need for more effective therapies in this patient population.
Unmet Needs in NMIBC
Despite available treatments, recurrence rates in NMIBC remain high, underscoring the necessity for improved therapeutic options. Activating FGFR alterations are present in a significant proportion (50% to 80%) of patients with advanced bladder cancer, making them potential oncogenic drivers.
Rationale for Intravesical Erdafitinib
Erdafitinib, a selective pan-FGFR tyrosine kinase inhibitor, has demonstrated efficacy in metastatic and advanced urothelial carcinoma and is approved for use following first-line systemic treatment. The THOR-2 study (NCT04172675) previously indicated activity with systemic erdafitinib in NMIBC. However, systemic adverse effects were deemed too significant for the NMIBC patient population. To mitigate these effects, TAR-210 was developed as an intravesical drug delivery system to administer erdafitinib locally, aiming to reduce systemic toxicities while preserving its efficacy.
Study Design and Patient Population
The phase 1 study included multiple cohorts, with data presented from cohorts 1 and 3. Cohort 1 comprised patients with high-risk NMIBC, specifically those with recurrent high-grade TA or T1 papillary tumors without carcinoma in situ, all of whom had previously been treated with BCG. Cohort 3 included patients with intermediate-risk NMIBC, characterized by a history of recurrent low-grade TA or T1 disease. All patients in this cohort had visible tumors in the bladder prior to treatment initiation. The study employed an accumulation design, and all patients in both cohorts had FGFR alterations identified through tissue samples or cell-free DNA from urine.
