A Study Comparing Abelacimab to Dalteparin in the Treatment of Gastrointestinal/Genitourinary Cancer and Associated VTE

Inclusion Criteria: * Male or female subjects ≥18 years old or other legal maturity age according to the country of residence * Confirmed GI (colorectal, pancreatic, gastric, esophageal, gastro-esophageal junction or hepatobiliary) or confirmed GU (renal, ureteral, bladder, prostate, or urethra) cancers if: * Unresectable, locally advanced, metastatic, or non-metastatic GI/GU cancer and * No intended curative surgery during the study * Confirmed symptomatic or incidental proximal lower limb deep vein thrombosis (DVT) (i.e., popliteal, femoral, iliac, and/or inferior vena cava vein thrombosis) and/or a confirmed symptomatic pulmonary embolism (PE), or an incidental PE in a segmental, or larger pulmonary artery. Patients are eligible within 120 hours from diagnosis of the qualifying VTE. * Anticoagulation therapy with LMWH for at least 6 months is indicated * Able to provide written informed consent Exclusion Criteria: * Thrombectomy, insertion of a caval filter, or use of a fibrinolytic agent to treat the current (index) occurrence of DVT and/or PE * More than 120 hours of pre-treatment with therapeutic doses of UFH, LMWH, or other anticoagulants * An indication to continue treatment with therapeutic doses of an anticoagulant other than for VTE treatment prior to randomization (e.g., atrial fibrillation, mechanical heart valve, prior VTE) * PE leading to hemodynamic instability (systolic BP \<90 mmHg or shock). * Acute ischemic or hemorrhagic stroke or intracranial hemorrhage, in the last 4 weeks preceding screening. * Brain trauma, or cerebral or a spinal cord surgery or spinal procedures such as lumbar puncture or epidural/spinal anesthesia within 4 weeks of screening * Need for aspirin in a dosage of more than 100 mg/day or, any other antiplatelet agent alone or in combination with aspirin * Bleeding requiring medical attention at the time of randomization or in the preceding 4 weeks * Planned brain, spinal cord, cardiac, vascular, major thoracic and/or major abdominal surgery in the 4 weeks following randomization * History of heparin induced thrombocytopenia * Infective acute or subacute endocarditis at the time of presentation * Primary brain cancer or untreated intracranial metastasis * Eastern Cooperative Oncology Group (ECOG) performance status of 3 or 4 at screening * Life expectancy of \<3 months at randomization * Calculated creatinine clearance (CrCl) \<30 mL/min at the screening visit * Platelet count \<50,000/ mm3 at the screening visit * Hemoglobin \<8 g/dL at the screening visit * Acute hepatitis, chronic active hepatitis, liver cirrhosis; or an alanine aminotransferase ≥3 times and/or bilirubin ≥2 times the upper limit of normal (ULN) at the screening visit in the absence of clinical explanation * Uncontrolled hypertension (systolic blood pressure \[BP\] \> 180 mm Hg or diastolic BP \>100 mm Hg despite antihypertensive treatment) * Women of child-bearing potential (WOCBP) who are unwilling or unable to use highly effective contraceptive measures during the study from screening up to 3 days after last treatment of dalteparin or 100 days after administration of abelacimab * Sexually active males with sexual partners of childbearing potential must agree to use a condom or other reliable contraceptive measure up to 3 days after last treatment of dalteparin or 100 days after administration of abelacimab * Pregnant or breast-feeding women * History of hypersensitivity to any of the study drugs (including dalteparin) or its excipients, to drugs of similar chemical classes, or any contraindication listed in the label for dalteparin * Subjects with any condition that in the judgement of the Investigator would place the subject at increased risk of harm if he/she participated in the study * Use of other investigational (not-registered) drugs within 5 half-lives prior to enrollment or until the expected pharmacodynamic effect has returned to baseline, whichever is longer. Participation in academic non-interventional studies or interventional studies, comprising testing different strategies or different combinations of registered drugs is permitted.