Ayvakyt is a cancer medicine used to treat gastrointestinal stromal tumour (GIST), a cancer of the stomach and bowel, that cannot be removed by surgery and has spread to other parts of the body. Ayvakyt is used when the cancer cells have a D842V mutation, a change in the gene for the platelet-derived growth factor receptor alpha (PDGFRA).

Ayvakyt is also used in adults with advanced systemic mastocytosis, which means any of the following disorders of a type of white blood cell known as mast cells: aggressive systemic mastocytosis, systemic mastocytosis associated with a haematological neoplasm (blood cancer), or mast cell leukaemia. It is used after the patient has received at least one systemic treatment (treatment with medicines affecting the whole body).

These diseases are rare, and Ayvakyt was designated an ‘orphan medicine’ (a medicine used in rare diseases) on 17 July 2017 (GIST) and on 26 October 2018 (mastocytosis).

Ayvakyt contains the active substance avapritinib.