Erdafitinib, sold under the brand name Balversa, is an anti-cancer medication. It is a small molecule inhibitor of fibroblast growth factor receptor (FGFR) used for the treatment of cancer. FGFRs are a subset of tyrosine kinases which are unregulated in some tumors and influence tumor cell differentiation, proliferation, angiogenesis, and cell survival. Astex Pharmaceuticals discovered the drug and licensed it to Janssen Pharmaceuticals for further development.