Common brand names

• Ayvakit

How it is administered

Avapritinib is administered as a film-coated tablet taken by mouth (orally). It is available in strengths of 25 mg, 50 mg, 100 mg, 200 mg, and 300 mg. The tablets should be taken on an empty stomach, at least 1 hour before or 2 hours after a meal. The typical dose for advanced systemic mastocytosis (AdvSM) is 200 mg once daily, but your doctor will determine the right dose for you.

How it works

Avapritinib is a type of medicine called a tyrosine kinase inhibitor. It works by blocking the activity of certain abnormal proteins (such as KIT D816V and PDGFRA mutations) that help cancer cells grow. By blocking these proteins, avapritinib can slow down or stop the growth of cancer cells, particularly in diseases like advanced systemic mastocytosis, which is a rare blood cancer involving abnormal mast cells.

This medication is especially effective in conditions where specific mutations are present that make the disease resistant to other treatments. It targets the abnormal signaling pathways that drive the uncontrolled growth of these cells, helping to reduce symptoms and disease burden.

Who should take it

Avapritinib is approved for adults with advanced systemic mastocytosis (AdvSM), which includes aggressive systemic mastocytosis, systemic mastocytosis with an associated hematological neoplasm, and mast cell leukemia. It is also used in adults with gastrointestinal stromal tumors (GIST) that have a specific PDGFRA exon 18 mutation.

For blood cancers, particularly those involving mast cells, avapritinib is considered when the disease is advanced or has not responded to other treatments. Your healthcare provider will determine if avapritinib is right for you based on your diagnosis, genetic mutations, and overall health.

Who should not take it

Avapritinib should not be used in patients with advanced systemic mastocytosis or indolent systemic mastocytosis who have a platelet count less than 50 × 10⁹/L. It should also be avoided in patients who are pregnant, as it can cause harm to an unborn baby. Women who are breastfeeding should not use avapritinib, and effective contraception is recommended during treatment and for a period after the last dose.

If you have a history of intracranial hemorrhage (bleeding in the brain), or are taking medications that increase bleeding risk, you should discuss this with your doctor. The safety and effectiveness in children have not been established.

Commonly used with

For advanced systemic mastocytosis and related blood cancers, avapritinib may be used alongside supportive care treatments such as antihistamines, corticosteroids, or other medications to manage symptoms. In some cases, it may be used after other treatments have failed.

It is important to inform your healthcare provider of all medications you are taking, as avapritinib can interact with other drugs, especially those that affect liver enzymes (CYP3A inhibitors or inducers).

Commonly tested with

Avapritinib is often tested in combination with best supportive care therapies, such as antihistamines and corticosteroids, especially in clinical trials for systemic mastocytosis. It is not typically combined with other cancer-targeted therapies, but your doctor will monitor your response and may adjust your treatment plan as needed.