• Overall response rate [ Time Frame: Every two months ]
  

• Progression-free-survival; Overall Survival; Safety [ Time Frame: Follow-up after end of treatment will be every three months; safety will be analyzed throughout the whole study ]
  

Inclusion Criteria:

• Age of > 18 years and < 72 years
• Patients with a histologically proven malignant mesothelioma of the pleura or of the peritoneum, expressing either PDFGR-beta or C-Kit by immunochemistry (ICH)
• Locally advanced disease, unsuitable for curative surgical resection, or metastatic disease
• Confirmed progression of the disease according to modified REcist-criteria, documented after a first-line, systemic (premetrex+cisplatin regimen) or local treatment (i.e., intrapleuric)
• ECOG Performance Status of 0, 1 or 2
• Life expectancy of at least 3 months
• Capability of understanding the objectives of the study and giving written informed consent
• Willingness and ability to comply with study requirements
• Sufficient caloric and fluid intake, including patients under enteral or parenteral nutrition

Exclusion Criteria:

• Co-existing tumors of different histologic origin, except non melanomatous localized skin cancer and/or in situ cervical carcinoma
• A history of earlier tumors of different histologic origin being in complete remission since less than 5 years
• Unresolved toxicity from prior antitumor treatment(s)
• Primary peritoneal mesothelioma

• Any of the following abnormal baseline hematological values:

  • Hb < 9 g/dL
  • WBC < 3 x 109/L
  • Neutrophils < 1.5 x 109/L
  • Platelets < 100 x 109/L
  • Serum bilirubin > 2.5 mg/dL
  • ALAT and ASAT > 3 x UNL (unless due to liver metastases)
  • Serum creatinine > 1.5 mg/dL
• Clinically relevant cardiovascular disease, i.e., myocardial infarction or other severe coronary artery diseases within the prior 6 months, cardiac arrythmia requiring medication, uncontrolled hypertension, overt cardiac failure or non compensated chronic heart disease in NYHA class II or more
• History of psychiatric disabilities, potentially interfering with the capability of giving adequate informed consent
• Pregnant or lactating women or inability/unwillingness to practice a medically approved method of contraception during study period (including 3 months following the end of treatment)
• Uncontrolled active infections
• Any condition which, in the judgement of the Investigator, would place the patient at undue risk or interfere with the results of the study