Infigratinib is a kinase inhibitor targeting FGFR1-3, indicated for the treatment of adult patients with locally advanced or metastatic cholangiocarcinoma harboring FGFR2 gene fusions or rearrangements.

What Are the Side Effects of Infigratinib?

Systemic Reactions

Skin and appendages: Nail toxicity (57%, including nail bed inflammation and onycholysis), alopecia (38%), palmar-plantar erythrodysesthesia syndrome (33%), xerosis (23%).

Digestive system: Stomatitis (56%, 15% grade 3), constipation (30%), abdominal pain (26%), xerostomia (25%), diarrhea (24%), vomiting (21%).

Ocular symptoms: Dry eye (44%), abnormal eyelash growth (25%), blurred vision (21%).

Laboratory Abnormalities

Hematology: Decreased hemoglobin (53%), lymphopenia (43%), thrombocytopenia (37%).

Biochemical indicators: Increased serum creatinine (93%), abnormal serum phosphorus (90% increased / 64% decreased).

Increased alkaline phosphatase (54%) and transaminases (ALT 51% / AST 38%).

Hyponatremia (41%), hyperuricemia (37%).

Serious Side Effects of Infigratinib to Be Alert For

Ocular Toxicity

Retinal pigment epithelial detachment (RPED).

May cause blurred vision; dose reduction or discontinuation may be required in severe cases (3.4% of patients required dose adjustment).

Management measures: A comprehensive ophthalmic examination including OCT is required before medication use.

Regular re-examinations at 1 month, 3 months after treatment initiation, and every 3 months thereafter.

Seek medical attention immediately if symptoms occur, and follow up every 3 weeks until resolution.

Hyperphosphatemia and Soft Tissue Calcification

May cause vascular/myocardial calcification, cutaneous calcinosis, etc.

Grading management:

Serum phosphorus >5.5mg/dL: Initiate phosphorus-lowering treatment.

Serum phosphorus >7.5mg/dL: Suspend administration until serum phosphorus ≤5.5mg/dL.

Serum phosphorus >9mg/dL or life-threatening cases: Permanently discontinue medication.

Embryo-Fetal Toxicity

Animal studies show teratogenicity; use is prohibited during pregnancy.

Contraceptive requirements:

Female patients: During treatment and for 1 month after discontinuation.

Male patients: During treatment and for 1 month after discontinuation.

Precautions for Infigratinib Use

Special Populations

Lactation: Breastfeeding is prohibited during treatment and for 1 month after discontinuation.

Elderly patients (≥65 years old): No dose adjustment is required.

Pediatric patients: Safety has not been established.

Monitoring During Treatment

Monitor serum phosphorus monthly until stable.

Regular ophthalmic follow-up (especially when visual symptoms occur).

Patient Education

Report abnormal symptoms such as vision changes, muscle spasms/perioral numbness.

Use artificial tears to prevent dry eye.

Avoid grapefruit products.