FGFR3 and bladder transitional cell carcinoma: Erdafitinib, an FGFR2/3 inhibitor approved as second-line for locally advanced or metastatic BLCa, was significantly more effective in samples harboring FGFR3 copy number gain (BLCa46, BLCa35, BLCa98) or gene amplification (BLCa33).