Standard usage and recommended dosage of erdafitinib/BOC

Erdafitinib (Erdafitinib) is a precise targeted drug that needs to be used based on genetic testing results, so confirming whether bladder cancer patients have FGFR2 or FGFR3 gene changes before treatment is a key step. The standard recommended dosage is derived from the drug's pharmacokinetic model and target inhibition intensity studies to ensure that the maximum FGFR pathway inhibition effect is achieved within a safe range. The usual starting dose is 8 mg orally once daily. After approximately two weeks of treatment, if the patient tolerates it well and does not experience significant adverse effects such as hyperphosphatemia, doctors may increase the dose to 9 mg daily to enhance the depth of FGFR inhibition. This gradual dose increase is a common strategy for targeted drugs, which can reduce initial discomfort and allow patients to transition to the optimal dose more smoothly.

During the course of medication, the doctor will decide whether to maintain the current dose or temporarily discontinue the medication based on blood phosphorus, liver and kidney function, eye examination, and the patient's overall tolerance. Since FGFR inhibitors may cause ocular reactions, such as blurred vision, central serous choroidopathy, etc., international guidelines generally recommend regular fundus examinations to ensure safety and controllability. For patients who experience adverse effects after taking the 9 mg dose, the dose may be restored to 8 mg or intermittent adjustments may be made. The drug is designed to be a sustained FGFR inhibitor, so taking it regularly and continuously is critical.

Erdafitinib needs to be used once a day. It is not recommended to increase or decrease the dose at will, nor should it be stopped without permission due to improvement of symptoms. Doctors often evaluate treatment response in conjunction with imaging to determine whether disease control, partial response, or stable state has been achieved. When the disease progresses or the patient cannot tolerate it, other treatment methods can be changed according to the situation.

In general, standard usage emphasizes three principles: genetic testing first, sequential dose increase, and close monitoring to ensure that the FGFR pathway can be stably inhibited while maintaining a safe and long-term treatment path.

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