In this study, the imatinib-resistant/intolerant patients were given an initial dosage of sunitinib 50 mg daily in 6-week cycles—4 weeks on treatment and 2 weeks off treatment. Tumor response was assessed using the Response Evaluation Criteria in Solid Tumors version 1.0.
Overall, the study included 1,124 patients in the intent-to-treat population, 15% of which had a baseline Eastern Cooperative Oncology Group performance status greater than or equal to 2.
Median values for treatment duration and tumor progression were analyzed [7.0 months and 8.3 months (95% CI: 8.0, 9.4 months), respectively]. The median overall survival was found to be 16.6 months (95% CI: 14.9, 18.0 months), with 36% of patients alive at the time of analysis.
Patients that had a modified initial dosing schedule had a longer median overall survival of 23.5 months compared with patients who were strictly treated using the initial dosing schedule (OS 11.1 months).
Treatment-related grade 3 and 4 adverse events included hand-foot syndrome (11%), fatigue (9%), neutropenia (8%), hypertension (7%), thrombocytopenia (6%), and those associated with cardiac function (e.g., congestive heart failure) (≤1%).
The objectives of this study were to provide sunitinib to patients with gastrointestinal stromal tumor (GIST) who were otherwise unable to obtain it and to collect broad safety and efficacy data from a large population of patients with advanced GIST after imatinib failure.