Erdafitinib treatment in Brazilian patients with metastatic urothelial carcinoma (mUC): real-world evidence from an Expanded Access Program

BACKGROUND: Erdafitinib is the first targeted therapy approved for the treatment of patients with metastatic urothelial carcinoma (mUC). Approval was based on a phase II single-arm trial that demonstrated significant activity of erdafitinib in patients with tumors harboring FGFR2/3 alterations. In Brazil, an Expanded Access Program (EAP) provided patients with early access to erdafitinib prior to market authorization. The current report describes characteristics and outcomes of patients with mUC on erdafitinib therapy. METHODS: Patients with mUC that failed first- and second-line systemic therapies were screened for FGFR2/3 alterations in primary or metastatic tumor tissues. Patients with FGFR2/3 alterations were selected to receive erdafitinib at the standard dosing schedule and were followed prospectively to evaluate the efficacy and safety outcomes. RESULTS: From 19 April 2019, through 13 March 2020, 47 patients with mUC from 10 Brazilian centers were tested for FGFR2/3 alterations. Alterations in FGFR2/3 were found in 12 patients (25.5%) and all of them were eligible for the EAP. Four patients (33%) had partial response, while two patients (17%) had stable disease. Progressive disease, the best response, was observed in five patients (42%). At a median follow-up of 16.2 months, the median time to treatment failure (TTF) was 2.8 months. When considering only patients with objective response, the median TTF was 5.3 months. Adverse events (AEs) were reported for any grade and grade 3 or higher in 10 patients (83%) and 5 patients (42%), respectively. The most common AE was hyperphosphatemia. CONCLUSION: This first real-world evidence report of heavily treated patients with mUC confirms the efficacy and safety of erdafitinib in a disease setting with a lack of treatment options.