About avapritinib
Tyrosine kinase inhibitor
Used for
- Unresectable or metastatic gastrointestinal stromal tumors with a PDGFRA exon 18 mutation, including D842V.
- Advanced systemic mastocytosis, including indolent, smoldering, and advanced forms.
Usual adult dose
GIST: 300 mg once daily. Advanced systemic mastocytosis: 200 mg once daily. Indolent or smoldering systemic mastocytosis: 25 mg once daily.
Common side effects
- Nausea, diarrhea, vomiting, and abdominal pain.
- Swelling, fatigue, and changes in hair or skin color.
- Low blood counts and abnormal liver tests.
- Cognitive effects, including memory problems, confusion, or sleepiness.
Important warnings
- Can cause intracranial bleeding; seek urgent care for severe headache or neurological symptoms.
- Can cause cognitive effects; avoid driving if affected.
- May cause serious harm to an unborn baby; effective contraception is required during treatment and afterward.
- Monitor blood counts, liver tests, and cognitive symptoms.
Pregnancy
May cause fetal harm. Avoid during pregnancy; effective contraception is required during treatment and for six weeks after the last dose.
Breastfeeding
Do not breastfeed during treatment and for two weeks after the last dose.
Interactions
- Strong or moderate CYP3A inhibitors can raise avapritinib levels; avoid or reduce dose as directed.
- Strong or moderate CYP3A inducers can lower levels; avoid concomitant use.
- Avapritinib may increase levels of certain CYP3A substrates; monitor for toxicity.
- Avoid St. John’s wort, which can reduce avapritinib levels.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.