A Study of the Efficacy and Safety of Imatinib Mesylate in Patients With Unresectable or Metastatic Gastrointestinal Stromal Tumors Expressing C-kit Gene
Condition: Unresectable or Metastatic Malignant Gastrointestinal Stromal Tumor (GIST)
MeSH terms: Gastrointestinal Stromal Tumors
Intervention: Imatinib mesylate
Intervention description: Participants were randomized 1:1 to receive imatinib mesylate 400 mg/day or 600 mg/day. Upon unsatisfactory treatment effect on the starting dose of 400 mg/day or 600 mg/day imatinib mesylate, in the opinion of the treating physician, a dose increase up to 600 mg/day or 800 mg/day, was allowed provided that the participant continued to benefit from the treatment and in the absence of safety concerns.
Intervention MeSH terms: Imatinib Mesylate
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Enrollment: 148.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No
Keywords: GIST; c-kit; imatinib mesylate

Summary:

      In the core study, participants with unresectable or metastatic gastrointestinal stromal
      tumors expressing c-kit were treated with either 400 mg or 600 mg imatinib mesylate for 3
      years. The 10 year extension study allowed participants, who successfully completed the core
      study, to continue study treatment with imatinib mesylate provided they still benefited from
      treatment and did not demonstrate safety concerns as per the investigator's opinion.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Men and non-pregnant women ≥18 years of age with the histopathologically documented
             diagnosis of malignant GIST that was unresectable and/or metastatic. Confirmation of
             KIT (CD117) expression via immunohistochemical analysis of tumor sample was also
             required

          -  At least one measurable lesion, as defined by Southwestern Oncology Group (SWOG) Solid
             Tumor Response Criteria, which had not been previously embolized or irradiated

          -  Performance status ≤3 as defined by the Eastern Cooperative Oncology Group (ECOG)
             criteria, as well as a life expectancy ≥6 months and adequate end organ function
             defined as follows: Total bilirubin <1.5 times upper limit of normal (ULN), aspartate
             aminotransferase (SGOT) and alanine aminotransferase (SGPT) <2.5 x ULN (or <5 x ULN if
             hepatic metastases were present), creatinine <1.5 x ULN, absolute neutrophil count
             (ANC) >1.5 x 10^9/L, platelet count >100 x 10^9/L

        Exclusion Criteria:

          -  Patients with fewer than five years of disease-free survival from any other (non-GIST)
             malignancy except if the other malignancy was not currently clinically significant and
             did not require active intervention or if the other malignancy was a basal cell skin
             cancer or a cervical carcinoma in situ

          -  Patients with known brain metastases

          -  Evidence of any of the following disorders: Grade III/IV cardiac failure as defined by
             the New York Heart Association Criteria, severe concomitant disease, acute or known
             chronic liver disease (i.e. chronic active hepatitis, cirrhosis) or HIV infection

          -  Chemotherapy or other investigational therapy within four weeks prior to study entry
             (six weeks for nitrosourea or mitomycin-C) and/or radiotherapy to ≥25% of the bone
             marrow

          -  Inability to cooperate

          -  Major surgery within two weeks or exposure to other investigational agents within 28
             days of entry into the study

        Other protocol-defined inclusion / exclusion criteria may have applied.