Abstract
Purpose: This work presents a case of secondary maculopathy associated with the use of erdafitinib (Balversa) for the management of bladder urothelial carcinoma with bony metastasis. Methods: A case report is presented. Results: A 58-year-old Hispanic man presented with blurry vision 3 weeks after starting erdafitinib for the management of bony metastases associated with urothelial carcinoma. A comprehensive evaluation identified multiple areas of subretinal fluid induced by erdafitinib. Throughout treatment, the ocular condition progressed, causing worsening of vision; this led to discontinuation of the drug. Discontinuation was associated with visual and anatomic function improvement. Conclusions: Fibroblast growth factor receptor (FGFR) plays a major role in maintaining mature and premature retinal pigment epithelium cells. Drugs that inhibit the FGFR pathway block the activation of the mitogen-activated protein kinase pathway, leading to synthesis of antiapoptotic proteins. Erdafitinib is associated with ocular toxicity and leads to multifocal pigment epithelial detachments associated with secondary subretinal fluid.