First results from the primary analysis population of the phase 2 study of erdafitinib (ERDA; JNJ-42756493) in patients (pts) with metastatic or unresectable urothelial carcinoma (mUC) and FGFR alterations (FGFRalt).

Abstract

4503Background: ERDA is an FGFR inhibitor with activity in pts with mUC and FGFRalt. FGFRalt occur in 10-20% of mUC and are enriched in immunologically “cold” luminal 1 UC. Two independent published reports showed a 5% investigator-reported response rate to prior immune checkpoint inhibitors (ICI) among pts with select FGFRalt, suggesting a need for new treatment options in this population. Here we report efficacy and safety of ERDA in the global open-label phase 2 study BLC2001 (NCT02365597). Methods: Pts had measurable mUC with prespecified FGFRalt, ECOG 0-2, and progression during/following ≥ 1 line of prior chemo or ≤ 12 mos of [neo]adjuvant chemo, or were cisplatin ineligible, chemo naive. Prior ICI treatment was allowed. The optimal schedule of ERDA determined in the initial part of the study was 8 mg/d continuous ERDA in 28-d cycles with uptitration to 9 mg/d if protocol-defined target serum phosphate level was not reached and if no significant treatment-related adverse events (TRAEs) occurred. Pri...