Pexidartinib Dosage

Medically reviewed by Drugs.com. Last updated on Nov 1, 2019.

Usual Adult Dose for Giant Cell Tumor of Bone

400 mg orally 2 times a day

Use: For symptomatic (TGCT) associated with severe morbidity or functional limitations and not amenable to improvement with surgery

Renal Dose Adjustments

Mild (CrCl 60 to 89 mL/min), moderate (CrCl 30 to 59 mL/min), or severe (CrCl 15 to 29 mL/min) renal impairment: 200 mg orally in the morning and 400 mg orally in the evening

Liver Dose Adjustments

-Mild hepatic impairment (total bilirubin less than or equal to upper limit of normal (ULN) with AST greater than ULN or total bilirubin greater than 1 to 1.5 times ULN with any AST): No adjustment recommended.
-Moderate (total bilirubin greater than 1.5 to 3 x ULN and any AST) to severe (total bilirubin greater than 3 to 10 x ULN and any AST) hepatic impairment: Dose adjustment(s) may be required; however, no specific guidelines have been suggested.

Dose Adjustments

DOSE REDUCTION RECOMMENDATION:
-First dose reduction: Reduce dose to 600 mg orally daily (200 mg in the morning and 400 mg in the evening).
-Second dose reduction: Reduce dose to 400 mg orally daily (200 mg orally 2 times a day).
-Permanently discontinue therapy in patients who are unable to tolerate 200 mg orally 2 times a day.

DOSE MODIFICATIONS FOR ADVERSE REACTIONS:
HEPATOTOXICITY:
-ALT and/or AST greater than 3 to 5 times the upper limit of normal (ULN): Withhold therapy and monitor liver tests weekly; if AST and ALT are less than or equal to 3 x ULN within 4 weeks, resume at reduced dose if AST or ALT is not less than or equal to 3 x ULN in 4 weeks, permanently discontinue therapy.
-ALT and/or AST greater than 5 to 10 x ULN: Withhold therapy and monitor liver tests 2 times a week; if AST and ALT are less than or equal to 3 x ULN within 4 weeks, resume therapy at reduced dose; if AST or ALT is not less than or equal to 3 x ULN in 4 weeks, permanently discontinue therapy.
-ALT or AST greater than 10 x ULN: Permanently discontinue therapy; monitor liver tests 2 times a week until AST or ALT is less than or equal to 5 x ULN, then weekly until less than or equal to 3 x ULN.
-ALP (confirm ALP elevations as liver isozyme fraction) greater than 2 x ULN with GGT greater than 2 x ULN: Permanently discontinue therapy; monitor liver tests 2 times a week until ALP is less than or equal to 5 x ULN, then weekly until less than or equal to 2 x ULN.
-Total bilirubin (TB) greater than ULN to less than 2 x ULN OR direct bilirubin (DB) greater than ULN and less than 1.5 x ULN: Withhold therapy and monitor liver tests 2 times a week. If an alternate cause for increased bilirubin is confirmed and bilirubin is less than ULN within 4 weeks, resume at reduced dose. If bilirubin is not less than ULN in 4 weeks, permanently discontinue therapy.
-TB greater than or equal to 2 x ULN OR DB greater than 1.5 x ULN: Permanently discontinue therapy; monitor liver tests 2 times a week until bilirubin is less than or equal to ULN.

ADVERSE REACTIONS OR OTHER LABORATORY ABNORMALITIES:
-Any severe or intolerable reaction: Withhold therapy until improvement or resolution; resume therapy at a reduced dose upon improvement or resolution.

CONCOMITANT USE OF STRONG CYP450 3A INHIBITORS OR UGT INHIBITORS:
-Avoid concomitant use of this drug with strong CYP450 3A inhibitors or UGT inhibitors.
-If concomitant use with a strong CYP450 3A inhibitor or UGT inhibitor cannot be avoided, reduce the pexidartinib dose.
- If concomitant use of a strong CYP450 3A inhibitor or UGT inhibitor is discontinued, increase the pexidartinib dose (after 3 plasma half-lives of the
strong CYP450 3A inhibitor or UGT inhibitor) to the dose that was used before starting the inhibitor.
RECOMMENDED DOSAGE REDUCTIONS FOR PEXIDARTINIB FOR CONCOMITANT USE OF STRONG CYP450 3A INHIBITORS OR UGT INHIBITORS:
-Pexidartinib planned dose of 800 mg daily: Reduce dose to 200 mg 2 times a day.
-Pexidartinib planned dose of 600 mg daily: Reduce dose to 200 mg 2 times a day.
-Pexidartinib planned dose of 400 mg daily: Reduce dose to 200 mg once a day.

CONCOMITANT USE OF ACID-REDUCING AGENTS:
-Avoid the concomitant use of proton pump inhibitors (PPI) with pexidartinib.
-As an alternative to a PPI, administer pexidartinib 2 hours before or 2 hours after taking a locally-acting antacid, or if using a histamine 2 (H2)-receptor antagonist, administer pexidartinib at least 2 hours before or 10 hours after taking an H2-receptor antagonist.

Precautions

The US FDA requires a Risk Evaluation and Mitigation Strategy (REMS) for pexidartinib. For additional information: http://www.accessdata.fda.gov/scripts/cder/rems/index.cfm

US BOXED WARNINGS:
HEPATOTOXICITY:
-This drug can cause serious and potentially fatal liver injury.
Recommendations:
-Monitor liver function tests prior to initiating this drug and at specified intervals
during therapy.
-Withhold and dose reduce or permanently discontinue therapy based on severity of hepatotoxicity.
-This drug is available only through a restricted program called the TURALIO
Risk Evaluation and Mitigation Strategy (REMS) Program

CONTRAINDICATIONS:
-None

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:
-This drug should be taken on an empty stomach, at least 1 hour before or 2 hours after a meal or snack.
-Capsules should be swallowed whole and not opened, broken, or chewed.
-If a dose is vomited or missed, it should be skipped, and the next dose should be taken at its scheduled time.

Storage requirements:
-Store at 20C to 25C (68F to 77F); excursions permitted to 15C to 30C (59F to
86F).
-Keep containers closed and do not remove desiccant from bottles.

Patient advice:
-Do not breastfeed during therapy and for 1 week after.
-Both males and females of reproductive potential taking this drug may experience impaired fertility.
-Tell your healthcare provider of all concomitant products (including over-the-counter products and supplements) that you are taking.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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