Brief Summary
This study consists of Dosethe amount of medication taken escalation part and Expansion part. In Dose Escalation Part, the maximum tolerated dose of combination of pimitespib and imatinib in patients with gastrointestinal stromal tumors (GIST) who are judged to be refractory to imatinib, estimate the recommended dose, evaluate safety and pharmacokinetics, and observe the antitumor effect. Expansion part consists of 3 arms. In Arm A, the efficacy and safety will be evaluated, which of the combination of pimitespib and imatinib in patients with GIST who have failed imatinib at doses below the MTD determined in Dose Escalation Part. In Arm B, the efficacy and safety of pimitespib monotherapy will be evaluated and the therapeutic effect of imatinib administration after pimitespib will be evaluated in an exploratory manner. In Arm C, the efficacy and safety of sunitinib monotherapy will be evaluated as reference data.
Intervention / Treatment
- Drug: Pimitespib
- Drug: Imatinib
- Drug: Sunitinib
Inclusion Criteria:
- Provided written informed consenta process in which a patient receives detailed information about a procedure or treatment, including its potential risks, benefits, and alternatives. The patient then has the opportunity to understand the information and voluntarily agree to the procedure or treatment.
- Histologically confirmed GIST
- Has radiographic progression based on RECIST 1.1 during or within 6 months of the last imatinib administration at enrollment. If surgerytreatment involving removal of cancerous tissue and/or tumours and a margin of healthy tissue around it to reduce recurrence/radiotherapy has been performed, radiographic progression based on RECIST 1.1 with imatinib must have been observed after the last surgery /radiotherapy
- Has at least one measurable lesion based on the RECIST version 1.1, except lymph nodessmall bean-shaped structures that filters harmful substances from lymph fluid (not dependent on size), which should be chosen as nontarget lesions;
- Eastern Cooperative Oncologythe study, diagnosis and treatment of cancer Group (ECOG) performance status of 0 to 1.