Drug Detail:Avapritinib (Avapritinib [ a-va-pri-ti-nib ])
Drug Class: Multikinase inhibitors
Usual Adult Dose for Stomach Cancer
300 mg orally once a day until disease progression or unacceptable toxicity
Use: For the treatment of adults with unresectable or metastatic GIST harboring a
platelet-derived growth factor receptor alpha (PDGFRA) exon 18 mutation, including PDGFRA D842V mutations
Renal Dose Adjustments
Mild (60 to less than 90 mL/min) to moderate (30 to less than 60 mL/min) renal impairment: No adjustment recommended.
Severe (15 to less than 30 mL/min) or end-stage (less than 15 mL/min) renal impairment: Data not available
Liver Dose Adjustments
Mild (total bilirubin less than or equal to upper limit of normal [ULN] and aspartate aminotransferase [AST] greater than ULN or total bilirubin greater than 1 to 1.5 times ULN and any AST) or moderate (total bilirubin greater than 1.5 to 3 x ULN and any AST) hepatic impairment: No adjustment recommended.
Severe hepatic impairment: Data not available
Dose Adjustments
RECOMMENDED DOSE REDUCTIONS:
- First dose reduction: 200 mg orally once a day
- Second dose reduction: 100 mg orally once a day
- Permanently discontinue therapy in patients unable to tolerate 100 mg orally once a day.
RECOMMENDED DOSE REDUCTIONS FOR ADVERSE REACTIONS:
INTRACRANIAL HEMORRHAGE:
Grade 1 or 2:
- First occurrence: Withhold this drug until resolution; resume at reduced dose.
- Subsequent occurrence: Permanently discontinue this drug.
- Permanently discontinue this drug.
- Grade 1: Continue at same dose or withhold until improvement to baseline or resolution; resume at same OR reduced dose.
- Grade 2 or 3: Withhold this drug until improvement to baseline, Grade 1, or resolution; resume at same OR reduced dose.
OTHER ADVERSE REACTIONS:
Grade 3 or 4: Withhold this drug until improvement to less than or equal to Grade 2; resume at same OR reduced dose.
Concomitant Use of Strong or Moderate CYP450 3A Inhibitors:
- Avoid concomitant use of this drug with strong or moderate CYP450 3A inhibitors.
- If concomitant use with a moderate CYP450 3A inhibitor cannot be avoided, reduce the starting dose of this drug from 300 mg once a day to 100 mg a day.
Precautions
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.
- Do not take an additional dose if vomiting occurs after taking this drug but continue with the next scheduled dose.
- If a dose is missed do not make up for a missed dose within 8 hours of the next
Storage requirements:
- Store at 20C to 25C (68F to 77F); excursions are permitted from 15C to 30C (59F to 86F).
