Avapritinib, brand name Ayvakit (formerly BLU-285), was approved January 9, 2020 by the FDA for gastrointestinal stromal tumors with a mutation in exon 18 of the platelet derived growth factor receptor alpha (PDGFRA), including the D842V mutation. These mutations have not responded to other approved tyrosine kinase inhibitors.

Avapritinib was developed by Blueprint Medicines Corporation. Link here to the Blueprint press release about Ayvakit approval.

The FDA approval statement summarizes results about avapritinib.

The full prescribing information sheet details trial results and side effects.

The NCI Drug Dictionary describes avapritinib as:
An orally bioavailable inhibitor of specific mutated forms of platelet-derived growth factor receptor alpha (PDGFR alpha; PDGFRa) and mast/stem cell factor receptor c-Kit (SCFR), with potential antineoplastic activity. Upon oral administration, avapritinib specifically binds to and inhibits specific mutant forms of PDGFRa and c-Kit, including the PDGFRa D842V mutant and various KIT exon 17 mutants. This results in the inhibition of PDGFRa- and c-Kit-mediated signal transduction pathways and the inhibition of proliferation in tumor cells that express these PDGFRa and c-Kit mutants. PDGFRa and c-Kit, protein tyrosine kinases and tumor-associated antigens (TAAs), are mutated in various tumor cell types; they play key roles in the regulation of cellular proliferation.

Blueprint Medicines Corporation’s website includes the following helpful booklet about how to take Avapritinib, potential side effects, and effectiveness in clinical trials:  Ayvakit Guide for Patients and Caregivers

For assistance with obtaining access to avapritinib, contact  YourBlueprint™, a patient support program that offers access and affordability solutions for individuals receiving AYVAKIT. For more information, visit YourBlueprint.com or call 1-888-BLUPRNT (1-888-258-7768), Monday to Friday, 8:00 a.m. to 8:00 p.m. ET.

Our GIST Support website includes an explanation of relevant PDGFRA mutations written by Dr. Suzanne George: Resistance Mutations in GIST.  Blueprint also has an educational webpage explaining the importance of mutations to drug effectiveness called Mutation Matters.

Avapritinib has also shown effectiveness against other mutations, including the exon 17 mutations in KIT that are often associated with resistance to Gleevec.  Avapritinib is currently being evaluated in a Phase III clinical trial (known as the Voyager trial) in which GIST patients who have previously taken 2 or 3 approved drugs are given either avapritinib or regorafenib, with crossover permitted.  This trial is ongoing but no longer recruiting.  The results, if positive, might lead to the approval of avapritinib for additional GIST categories.  For details about the Voyager trial link to its Blueprint page or NCT03465722     Updates on the results of the Voyager trial are expected in late spring of 2020.

Previous news items about avapritinib on our website include these: