TINzaparin Prophylaxis in Patients With Metastatic Colorectal Cancer

Inclusion Criteria:

1. Male or female subjects with age ≥ 18 years.
2. Written informed consent.
3. Patients with a histologically confirmed diagnosis of stage IV colon or rectal adenocarcinoma (mCRC).
4. Locally assessed BRAF and RAS genomic alterations available during screening.
5. Beginning of the first line of treatment for metastatic disease with chemotherapy +/- targeted therapy (i.e. antiangiogenic, anti-EGFR, encorafenib-cetuximab doublet) or immunotherapy.
6. Eastern Cooperative Oncology Group (ECOG) performance status of 0-2.
7. Life expectancy \>6 months.

Exclusion Criteria:

1. Contraindication to tinzaparin, or other heparins:

   1. Allergy (or hypersensitivity) to heparin, tinzaparin, other LMWHs, or pork products.
   2. History or presence of heparin-induced (type II) thrombocytopenia.
   3. Have or have had an epidural catheter or a traumatic spinal puncture within the previous 7 days.
2. Prothrombin time (PT) (International normalized ratio \[INR\] \>1.5 for any reason) or aPTT \>2 times control value.
3. Active major bleeding or conditions predisposing to major bleeding. a major bleeding is defined as one that meets one of the following three criteria:

   1. occurring in a critical area or organ (for example, intracranial, intra-spinal, intraocular, retroperitoneal, intra-articular or pericardial, intrauterine or intramuscular with compartment syndrome),
   2. causing a decrease in hemoglobin levels of 2 g/l (1.24 mmol/l) or more, or that requires a transfusion of two or more units of whole blood or packed red blood cells.
4. Lesions or conditions at increased risk of clinically significant bleeding, including:

   1. Previously diagnosed/treated VTE ≤ 28 days prior to randomization.
   2. Active ulcer disease.
   3. Diagnosed cerebral metastases.
   4. Stroke within the prior 6 months.
   5. History of central nervous system (CNS) or intraocular bleeding.
5. Requirement of other anticoagulant therapy, dual antiplatelet therapy, daily non-steroidal anti-inflammatory drugs, or other medications known to increase the risk of bleeding.

   Note: A daily dose of ≤100 mg of aspirin and single agent clopidogrel are permitted
6. Acute or chronic renal insufficiency with Creatinine clearance \< 30 ml / min.
7. Platelet count \< 80.000 /ml at the time of inclusion.
8. Severe liver insufficiency as defined by clinical manifestations of ascites, cirrhosis, encephalopathy and/or jaundice and/or biochemical abnormalities in liver function tests including:

   1. elevated levels of total bilirubin (\> 2 times the upper limit normal \[ULN\]),
   2. elevated liver transaminases (\> 2 times the ULN; \> 5 in case of hepatic metastasis).
9. Participating in another study of an investigational agent at the time of enrollment. Note: Use of an experimental regimen of an approved product is not cause for exclusion.
10. Patients who weigh \< 50 Kg.
11. Women of childbearing potential (WOCBP), must provide a negative serum or urine pregnancy test at screening. Women breastfeeding are not eligible.

    Note: A pregnancy test is performed on WOCBP as per standard of care for patients undergoing anticancer treatments.
12. Any underlying medical or psychiatric disorder, which, in the opinion of the investigator, makes the administration of tinzaparin unsafe or interferes with the informed consent process or trial procedures.