avapritinib at a glance
Medicine class
Tyrosine kinase inhibitor
Licensed use
PDGFRA D842V-mutated GIST that is inoperable or metastatic
How it is taken
Swallowed whole with water on an empty stomach
Important risks
Bleeding, cognitive effects, fluid retention and QT prolongation
What is avapritinib used for?
The selected UK product is licensed as monotherapy for:
Adults with unresectable or metastatic GIST confirmed by validated testing to carry the PDGFRA D842V mutation.
How does avapritinib work?
Avapritinib blocks abnormal kinase signalling driven by mutant PDGFRA, particularly PDGFRA D842V. This signalling can promote tumour-cell growth and survival; blocking it can restrain the tumour.
avapritinib preparations and strengths
Tablet
Route: Oral
Strengths: 25 mg, 50 mg, 100 mg, 200 mg, 300 mg
How to take avapritinib
Follow the specialist treatment plan and do not alter treatment without their advice.
Take on an empty stomach.
Swallow the tablet whole with a glass of water.
Minimise direct sunlight and use protective clothing and high-factor sunscreen because photosensitivity can occur.
avapritinib side effects
Common or expected effects
- Swelling, particularly around the eyes, face or limbs
- Nausea, diarrhoea, vomiting or abdominal discomfort
- Tiredness and anaemia
- Reduced appetite
- Memory, concentration or other cognitive changes
- Dizziness or altered taste
- Increased tearing
- Raised bilirubin or liver enzymes
- Rash or hair-colour changes
Get urgent medical advice
- Sudden severe headache, visual disturbance, marked drowsiness or focal weakness, which may indicate intracranial bleeding
- Blood in vomit or stools, black stools or other significant bleeding
- New or worsening confusion, forgetfulness, speech difficulty or impaired thinking
- Rapid weight gain, increasing swelling or breathlessness suggesting significant fluid retention
- Fainting, palpitations or severe dizziness that could indicate an abnormal heart rhythm
avapritinib in pregnancy
Avapritinib is not recommended during pregnancy because animal studies indicate potential fetal harm and human pregnancy data are unavailable. Pregnancy status should be checked before treatment. Effective contraception is required during treatment and for six weeks afterwards for patients who could become pregnant, and during treatment and for two weeks afterwards for males with partners who could become pregnant. Contact the specialist team promptly if pregnancy occurs or is suspected.
avapritinib while breastfeeding
It is unknown whether avapritinib enters human milk, and harm to a breastfed infant cannot be excluded. Breastfeeding should stop during treatment and for two weeks afterwards; discuss feeding options with the specialist team.
avapritinib interactions
The specialist team and pharmacist should review all prescribed, non-prescribed and herbal products.
Strong or moderate CYP3A inhibitors, including azole antifungals, clarithromycin, erythromycin, ritonavir and cobicistat
These can increase avapritinib exposure and adverse effects, so concurrent use should generally be avoided.
Grapefruit or grapefruit juice
Grapefruit can increase avapritinib exposure and should be avoided.
CYP3A inducers, including rifampicin, carbamazepine, phenytoin, phenobarbital and St John’s wort
These can substantially lower avapritinib exposure and reduce its effect, so concurrent use should be avoided.
Common questions about avapritinib
Answers are fully visible for fast scanning and source review.
Why is PDGFRA D842V testing required?
The licence is mutation-specific, so validated testing is needed to confirm that the tumour carries the target alteration.
Is avapritinib chemotherapy?
It is a targeted anticancer treatment called a tyrosine kinase inhibitor rather than traditional cytotoxic chemotherapy.
Can avapritinib affect memory or thinking?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.