Patients in the study had imatinib refractory GIST. They received dasatinib 70 mg twice daily. They were enrolled in 2008-2009 and followed for at least 5 years.
In addition to previously receiving imatinib, most enrollees (80%) had already been treated with sunitinib as well. The study started before the approval of sunitinib in GIST, but after the approval of regorafenib, the investigators noted.
“Preclinical research suggested that dasatinib had higher potency against mutations in the activation domain of KIT and PDGFRA than imatinib and sunitinib,” the authors recounted.
This trial did provide some evidence in support of that preclinical data: One patient with a specific mutation in PDGFRA exhibited prolonged tumor control.
Bristol-Myers Squibb provided funding for the trial and dasatinib. Dr. Schuetze reported disclosures related to Novartis, Amgen, Janssen, Daiichi-Sankyo, Eli Lilly, and AB Science.
SOURCE: Schuetze SM et al. 2018 Apr 26. doi: 10.1001/jamaoncol.2018.0601.