Pemigatinib Dosage and Administration

Pemigatinib is a kinase inhibitor indicated for the treatment of adult patients with previously treated, unresectable locally advanced or metastatic cholangiocarcinoma with a fibroblast growth factor receptor 2 (FGFR2) fusion or rearrangement as detected by an approved test.

Pemigatinib Dosage and Administration

1. Recommended Dosage

(1) Dose: 13.5 mg orally once daily.

(2) Dosing Schedule: Administer for 14 consecutive days, followed by 7 days of no treatment, constituting a 21-day treatment cycle.

(3) Administration: Swallow tablets whole. May be taken with or without food.

(4) Timing: Take at approximately the same time each day.

2. Important Administration Instructions

(1) Tablets must be swallowed whole. Do not crush, chew, break, or dissolve tablets.

(2) If a dose is missed by more than 4 hours or vomiting occurs after taking a dose, do not make up the dose. Take the next dose at the regularly scheduled time the following day.

(3) Continue treatment until disease progression or unacceptable toxicity occurs.

Pemigatinib Dose Modifications

1. Dose Modifications for Adverse Reactions

(1) First Dose Reduction: 9 mg once daily for 14 days followed by 7 days off treatment (21-day cycle).

(2) Second Dose Reduction: 4.5 mg once daily for 14 days followed by 7 days off treatment (21-day cycle).

(3) Permanently discontinue pemigatinib if the patient is unable to tolerate the 4.5 mg once daily dose.

2. Retinal Pigment Epithelial Detachment (RPED)

(1) Asymptomatic with stable findings: Continue current dose.

(2) Symptomatic or worsening findings: Withhold dose.

(3) If findings improve and become asymptomatic upon follow-up: Resume treatment at a reduced dose.

(4) If symptoms persist or findings do not improve: Consider permanent discontinuation.

3. Hyperphosphatemia

(1) Serum phosphorus >7 mg/dL but ≤10 mg/dL:

Initiate phosphate-lowering therapy and monitor serum phosphorus weekly.

If serum phosphorus does not decrease to <7 mg/dL within 2 weeks, withhold the dose.

After recovery: Resume at the same dose for the first occurrence; reduce the dose for recurrence.

(2) Serum phosphorus >10 mg/dL:

Initiate phosphate-lowering therapy and monitor serum phosphorus weekly.

If serum phosphorus does not decrease to ≤10 mg/dL within 1 week, withhold the dose.

After recovery, resume at a reduced dose.

Permanently discontinue if recurrence of >10 mg/dL occurs after two dose reductions.

Pemigatinib Use in Specific Populations

1. Renal Impairment

(1) Mild to moderate renal impairment (GFR 30-89 mL/min): No dosage adjustment is recommended.

(2) Severe renal impairment (GFR <30 mL/min): The recommended dosage has not been established.

2. Hepatic Impairment

(1) Mild hepatic impairment (bilirubin ≤1.5 × ULN or AST > ULN): No dosage adjustment is recommended.

(2) Moderate hepatic impairment (bilirubin 1.5-3 × ULN): No dosage adjustment is recommended.

(3) Severe hepatic impairment (bilirubin >3 × ULN): The recommended dosage has not been established.

3. Pregnancy

(1) Pemigatinib may cause fetal harm. It is contraindicated in pregnant women.

(2) Verify pregnancy status in females of reproductive potential prior to initiating treatment.

(3) Females of reproductive potential should use effective contraception during treatment and for 1 week after the final dose.

(4) Males with female partners of reproductive potential should use effective contraception during treatment and for 1 week after the final dose.

4. Lactation

(1) It is unknown whether pemigatinib is excreted in human milk.

(2) Advise women to discontinue breastfeeding during treatment and for 1 week after the final dose.