Inavolisib at a glance
Medicine class
PI3K-alpha inhibitor and mutant p110-alpha degrader
Licensed role
Targeted treatment for selected PIK3CA-mutated, ER-positive, HER2-negative advanced breast cancer
Patient selection
A validated tumour or plasma test must confirm a PIK3CA mutation
Administration
Film-coated tablets taken with or without food and swallowed whole
What is Inavolisib used for?
The licence covers a defined breast-cancer setting:
With palbociclib and fulvestrant for adults with PIK3CA-mutated, ER-positive, HER2-negative locally advanced or metastatic breast cancer that recurred during, or within 12 months after, adjuvant endocrine treatment.
For premenopausal or perimenopausal women and men, the endocrine treatment also includes an LHRH agonist.
How does Inavolisib work?
PIK3CA mutations can overactivate the PI3K growth pathway. Inavolisib inhibits the p110-alpha protein and promotes degradation of its mutated form, reducing signals that support cancer-cell growth and survival.
Inavolisib preparations and strengths
Tablet
Route: Oral
Strengths: 3 mg, 9 mg
How to take Inavolisib
Take inavolisib exactly as directed by the specialist cancer team.
It may be taken with or without food.
Swallow tablets whole; do not chew, crush, dissolve or divide them.
Do not take a broken, cracked or otherwise damaged tablet.
Inavolisib side effects
Common or expected effects
- High blood sugar
- Sore or inflamed mouth, including ulcers
- Diarrhoea
- Low platelet or red-cell counts
- Tiredness
- Nausea or vomiting
- Reduced appetite and weight loss
- Rash, dry skin or hair thinning
- Headache
- Abdominal pain
- Urinary tract infection
- Changes in liver enzymes or potassium shown by blood tests
Get urgent medical advice
- Severe high blood sugar or ketoacidosis
- Unusual or significant bleeding associated with low platelets
- Severe or persistent diarrhoea, particularly with dehydration
- Severe anaemia or infection requiring urgent assessment
Inavolisib in pregnancy
Inavolisib is not recommended during pregnancy because animal studies indicate potential fetal harm and human information is limited. Pregnancy status should be checked before treatment. People who could become pregnant should use effective non-hormonal contraception. Male patients with a pregnant partner or one who could become pregnant should use condoms during treatment and for 1 week afterwards. Contact the oncology team immediately if pregnancy occurs.
Inavolisib while breastfeeding
It is unknown whether inavolisib enters human milk, and harm to a breastfed child cannot be excluded. Breastfeeding should stop during treatment and for 1 week after the last dose; discuss feeding options with the specialist team.
Inavolisib interactions
Formal interaction studies have not been performed. Inavolisib may alter exposure to medicines processed by several CYP enzymes. The specialist team should review all prescription, non-prescription and herbal products.
Ciclosporin, sirolimus, tacrolimus, alfentanil, quinidine or other narrow-therapeutic-index CYP3A4 substrates
Exposure may increase or decrease, potentially changing efficacy or toxicity.
Warfarin
Exposure may decrease, altering its anticoagulant effect.
Phenytoin or S-mephenytoin
Exposure may decrease, potentially reducing seizure control.
Common questions about Inavolisib
Answers are fully visible for fast scanning and source review.
Why is a PIK3CA test needed?
The treatment targets a pathway driven by PIK3CA mutations, and the licence requires confirmation of an eligible mutation in tumour tissue or plasma.
Is inavolisib chemotherapy?
It is a targeted anticancer treatment rather than conventional cytotoxic chemotherapy.
Can it be taken with food?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.