A Study of Oral Erdafitinib in People With Recurrent Non-Invasive Bladder Cancer

Participants will receive erdafitinib at a dose of 6 mg orally once daily for the first 14 days (±3 days). Serum phosphate levels will be assessed on day 14 (±3 days) and the dose of erdafitinib may be lowered based on the serum phosphate level. Treatment with erdafitinib at a dose of 6 mg orally once daily, or at a lower dose level for another 14 days (±3 days) until the day of their standard-of-care TURBT/biopsy. Standard-of-care TURBT/biopsy will be performed after approximately 28 days (±5 days) from the start of treatment with erdafitinib, and biologic and pathologic tumor response will be assessed. All participants will then be followed up for recurrence or progression in accordance with the standard of care.