LAUSR

FGFR inhibitors represent a new and promising therapeutic approach to urothelial cancer (UC). Erdafitinib (Balversa©) was the first FGFR inhibitor approved for the treatment of metastatic UC, showing proper pharmacological activity and a consistent safety profile in a population with limited or no therapeutic alternatives. While results from comparative phase II and III trials are needed to assess the efficacy of erdafitinib in different clinical settings, there are still questions unsolved regarding a typical class effect of FGFR inhibitors, hyperphosporemia. In this review, the authors focus on the state-of-art administration of erdatifinib in advanced UC, pointing out the more recent evidence, pitfalls and possible future research. Insight on the management of hyperphosporemia in patients undergoing treatment with FGFR inhibitors is also provided.