The recommended dose is 20 mg (five 4 mg tablets) orally once daily until disease progression or intolerance. 

Dosing Regimen and Modifications

Tablets must be swallowed whole, with or without food, at consistent times. Dose reductions (16 mg or 12 mg daily) are mandated for severe hyperphosphatemia or grade ≥3 adverse reactions, with permanent discontinuation if toxicity persists at 12 mg. Missed doses beyond 12 hours or post-vomiting require resumption at the next scheduled dose without compensation. Pre-treatment ophthalmologic exams and periodic serum phosphate monitoring are essential. Concomitant use of dual P-gp/CYP3A inhibitors or inducers is contraindicated due to altered futibatinib exposure.