A Phase 2 Study to Evaluate the Efficacy and Safety of Temozolomide in Advanced Gastrointestinal Stromal Tumor Patients With SDH Deficiency
The goal of this clinical trial is to investigate the efficacy and safety of temozolomide in SDH deficiency GIST patients.
⁃ Age 20 years or older, at the time of acquisition of informed consent
⁃ Histologically confirmed GIST with CD117(+), DOG-1(+)
⁃ Wild type GIST without KIT or PDGFRα gene mutations determined by Sanger sequencing and panel sequencing
⁃ Eastern Cooperative Oncology Group (ECOG) performance status 0 \
• 2
⁃ Resolution of all adverse events with prior treatments to grade 0 or 1 by NCI-CTCAE version 5.0
⁃ At least one measurable lesion by RECIST version 1.1.
⁃ Adequate bone marrow, hepatic, renal, and other organ functions, before adjuvant imatinib treatment
∙ Neutrophil \>1,500/mm3
‣ Platelet \> 100,000/mm3
‣ Hemoglobin \>8.0 g/dL
‣ Total bilirubin \< 1.5 x upper limit of normal (ULN)
‣ AST/ALT \< 2.5 x ULN
‣ Creatinine \<1.5 x ULN
⁃ Life expectancy ≥12 weeks
⁃ Disease progression or discontinuation of treatment due to intolerable toxicity at least with palliative 1st line imatinib .
‣ Washout period of previous TKIs or chemotherapy for more than 4 times the half life ((Imitinib and regorafenib need 1 week and sunitinib need 2 weeks.)
‣ Provision of a signed written informed consent