Erdafitinib: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
Erdafitinib: clinical details
Prescribing considerations
- Confirm a susceptible FGFR3 genetic alteration using a validated test before initiation.
- Treatment should be initiated and supervised by a clinician experienced in anticancer therapy.
- Review concomitant products for CYP2C9, CYP3A4, P-glycoprotein, QT and phosphate-related interactions.
- Data are absent or limited in severe renal or hepatic impairment; consider alternatives.
- Provide preventive advice for dry eyes, oral care, skin care, nail care and sun protection.
Contraindications and cautions
- Hypersensitivity to erdafitinib or any excipient.
- Use particular caution with clinically significant retinal disease, previous retinal detachment, QT-risk factors or uncontrolled phosphate disturbance.
Monitoring
- Baseline ophthalmological assessment, including visual acuity, fundoscopy and an Amsler grid; include optical coherence tomography where available.
- Regular ophthalmological examinations and urgent assessment of visual symptoms.
- Serum phosphate throughout treatment and during interruptions, with assessment for mineralisation and associated electrolyte abnormalities.
- Regular full blood count, renal function, liver tests, sodium and other serum chemistries.
- Pregnancy testing before treatment when relevant.
Clinical pharmacology
Erdafitinib is an oral pan-FGFR tyrosine kinase inhibitor. It is metabolised mainly by CYP2C9 and CYP3A4, inhibits P-glycoprotein and has a long effective half-life. Increased serum phosphate is an expected consequence of FGFR inhibition.
Formulation and product differences
- The selected product is a yellow, round, biconvex film-coated tablet marked with its strength on one side and “EF” on the other.
- The tablets are intended to be swallowed whole.
Erdafitinib preparations and strengths
Tablet
Route: Oral
Strengths: 3 mg, 4 mg, 5 mg
Erdafitinib interactions
Ask the cancer pharmacist to check all prescribed, over-the-counter, herbal and complementary products.
Moderate CYP2C9 or strong CYP3A4 inhibitors, including fluconazole, itraconazole, clarithromycin and ritonavir
May increase erdafitinib exposure and toxicity; an alternative or specialist adjustment may be required.
Strong or moderate CYP3A4 inducers, including carbamazepine, phenytoin and rifampicin
May reduce erdafitinib exposure and effectiveness; strong inducers are not recommended.
St John’s wort
May reduce erdafitinib exposure and effectiveness.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.