Avapritinib is primarily used in the treatment of certain types of cancer, particularly gastrointestinal stromal tumors (GIST) that are associated with specific genetic mutations. It is effective in targeting and inhibiting mutated forms of the KIT and PDGFRA proteins, which are often responsible for the growth and proliferation of these cancer cells. This makes it a valuable option for patients who have not responded well to other treatments or have developed resistance to standard therapies. In addition to GIST, avapritinib is also being investigated for its potential in treating other cancers driven by similar genetic alterations. Its ability to selectively target and block the activity of these mutated proteins helps to slow down or stop the progression of the disease, offering hope for improved outcomes in patients with limited treatment options. The drug is typically administered orally, making it convenient for long-term use in managing these conditions.