AVIATOR2020

GIST are rare mesenchymal tumors of the gastrointestinal tract characterized by somatic mutations in the gene encoding the KIT (85%) or the PDGFRα (8%) protein. Treatment of localized forms relies on adequate surgery without tumor spillage and sometimes systemic treatment with imatinib according to risk of relapse defined by localization, tumor size and mitotic count, as well as mutational status. More than 40% of cases may recur and metastasize. Advanced and relapsing forms are currently treated with oral tyrosine-kinase inhibitors (TKI) of KIT and PDGFR such as imatinib (standard treatment), sunitinib (2nd line) and regorafenib (3rd line). Nevertheless, imatinib has little or no activity in patients harboring the D842V mutation in the exon 18 of PDGFRα (20% of gastric GIST, 6% of all GIST patients). Consequently, other therapeutic alternatives are needed.

Results from the phase I single-arm NAVIGATOR study show that avapritinib has significant efficacy in GIST patients with PDGFRα D842V mutation (ORR = 86 %). In France, an authorization for temporary use (ATUc) starting on September 21st, 2020 has been granted by the National Agency for Safety of Medicines and Health Products (ANSM). It allows the early availability of avapritinib in France while waiting for Market Authorization Approval (AMM). This ATUc will be accompanied by a protocol of therapeutic use and collection of information (PUT) that describes the frequency of patient visits.

The objective of this real-life registry is to perform a long-term longitudinal follow up of PDGFRA D842V-mutated GIST patients treated with avapritinib and to collect effectiveness and safety data. It will be implemented in parallel to the ATUc until June 2023.

Data from the electronic health record (EHR) will be collected. Moreover, as per the ANSM's requirements, quality of life and cognitive function will be investigated using FACT-G, FACT-Cog and MoCA questionnaires.

Undesirable effects will be collected as well. Follow-up is envisioned for a minimum of 2 years.