Erdafitinib Disease Interactions

Increases in phosphate levels are a pharmacodynamic effect of erdafitinib. Hyperphosphatemia was reported as adverse reaction in 76% of patients after initiating treatment, with 32% requiring phosphate binders during treatment. Caution and monitoring of phosphate levels is advised in all patients, especially in those at risk or hyperphosphatemia. Follow the manufacturer's dose modification guidelines if required.

Erdafitinib can cause ocular disorders, including central serous retinopathy/retinal pigment epithelial detachment (CSR/RPED) resulting in visual field defect. Perform monthly ophthalmological examinations during the first 4 months of treatment and every 3 months afterwards, and urgently at any time for visual symptoms. Ophthalmological examination should include assessment of visual acuity, slit lamp examination, fundoscopy, and optical coherence tomography. Caution and close monitoring is advised in patients with retinal disorders. Follow manufacturers dose modification guidelines in patients at risk or with ocular adverse reactions.

The pharmacokinetics of erdafitinib in patients with severe renal impairment, renal impairment requiring dialysis, moderate or severe hepatic impairment is unknown. Caution is advised if used in these patients.