Drug Trial to Investigate the Safety and Efficacy of Niclosamide Tablets in Patients With Metastases of a Colorectal Cancer Progressing After Therapy

Inclusion Criteria: * Patient with metachronous or synchronous metastases of a colorectal cancer progression under standard therapy * no proven brain metastases * no curative option * no standard therapy available * Age \> 18 years * At least one metastases measurable according to Response Evaluation Criteria In Solid Tumors V 1.1 in CT or MRI scan not older than 2 weeks before inclusion into the trial * Lab values within the usual borders for these patient group e.g. * Neutrophil ≥ 1.5x109/ •Platelets ≥ 100x109/L * Leukocytes ≥ 1.0x109/L * Hemoglobin ≥ 9.0 g/dL or 5.59 mmol/l * Bilirubin ≤ 2 x Upper Limit of Normal (ULN) if not due to Gilbert's syndrome * Aspartate Aminotransferase ≤ 2.5x Upper Limit of Normal in patients without liver metastases or ≤ 5.0x Upper Limit of Normal in patients with liver metastases * Alanine aminotransferase ≤ 2.5x Upper Limit of Normal in patients without liver metastases \< 5.0 x Upper Limit of Normal in patients with liver metastases * adequate renal function (creatinin ≤ 1.5x Upper Limit of Normal) * Eastern Cooperative Oncology Group 0 - 1 * EKG without clinical significant abnormalities * No other malignant disease (except colorectal cancer) within the last 5 years before inclusion in the trial except adequately treated basal cell carcinoma of the skin or squamous cell carcinoma of the skin, in situ carcinoma of the cervix. Patients with a malignant disease in history have to be free of disease for 5 years. * No clinical significant heart disease like e.g. * Uncontrolled blood pressure * Heart failure New York Heart Association grade \> 2 * Cardiac infarction within the last 12 months * No known uncontrolled concomitant disease despite treatment like e.g. * Chronic obstructive pulmonary disease (COPD) * Serious infections * No known alcohol or drug abuses * Absence of any psychological, familial, sociological or geographical condition, potentially hampering compliance with the study protocol and follow-up schedule * Patients should use adequate birth control measures, during the study treatment period and for at least 3 months after the last study treatment. * For women of childbearing potential (WOCBP):negative pregnancy test 72 hours before the application of the first dose if the study drug * Patients who are breastfeeding must stop breastfeeding before the first dose of the study drug and not restart till 8 week after the last drug intake. * Written informed consent before inclusion according to the International Conference on Harmonisation good clinical practice (ICH GCP) and national/local regulations Exclusion Criteria: * Life expectancy \< 3 months * Participation in another interventional study within the last 30 days * Known hypersensitivity against a part of the study drug * Pregnancy or breastfeeding * HIV infection oder active hepatitis B/C