Erdafitinib

Treatment should be initiated and supervised by a physician experienced in the use of anticancer therapies. Confirmation of susceptible FGFR3 gene alteration(s) by a validated test method is required before starting. Serum phosphate should be assessed prior to the first dose and monitored monthly; after day 21 the serum phosphate level should not be used to guide up-titration. For phosphate concentrations >=5.5 mg/dL (1.75 mmol/L) restrict dietary phosphate intake to 600-800 mg/day; 7.00-8.99 mg/dL continue and start a phosphate binder; 9.00-10.00 mg/dL withhold until <7.00 mg/dL then restart at the same dose level; >10.00 mg/dL withhold until <7.00 mg/dL then restart at the first reduced dose level, and discontinue permanently if >=10.00 mg/dL is sustained for more than 2 weeks. Discontinue permanently for significant alteration from baseline renal function or Grade 3 hypocalcaemia due to hyperphosphataemia. Baseline and monthly ophthalmological examination (including Amsler grid) during the first 4 months, then every 3 months and urgently for any visual symptoms; all patients should receive dry-eye prophylaxis with ocular demulcents at least every 2 hours during waking hours. Treatment should continue until disease progression or unacceptable toxicity. Missed dose: take as soon as possible and resume the regular daily schedule the next day; do not take extra tablets. If vomiting occurs at any time after a dose, take the next dose the next day. Hepatic impairment: no adjustment for mild or moderate; limited data in severe - consider alternative treatment. Elderly: no specific dose adjustment; limited data above 85 years. Paediatric: there is no relevant use of erdafitinib in the paediatric population for urothelial carcinoma and safety/efficacy in patients under 18 years have not been established. Grapefruit and Seville oranges should be avoided. Interactions listed below are taken from the US prescribing information section 7 - the eMC section 4.5 text was not captured in this source extract.