Secondary Prevention of VTE in Patients With Cancer and Catheter-Related Upper Extremity Deep Vein Thrombosis

The aim of the STREAM-Line Trial is to demonstrate that the STREAM-Line management strategy is safe after the acute treatment duration (≥ 3 months of therapeutic anticoagulation) in patients with cancer and catheter-related upper extremity DVT. Upon enrollment and during follow-up, patients will be managed with a prophylactic dose of apixaban (2.5 mg orally twice daily) as long as either a central venous catheter (CVC) or active cancer is present (STREAM-Line management strategy). Apixaban will be stopped at the time of CVC removal and when cancer is in remission. Day 90±14 and Day 180+14 follow-up visit procedures will be done by phone call or in person.

• Anticoagulation Therapy (Drug), also known as Apixaban: Patients will be enrolled after at least 3 months of therapeutic anticoagulation for an acute catheter-related upper extremity DVT while they are treated with therapeutic anticoagulation as standard of care. After enrollment, patients will be managed with prophylactic dose of anticoagulation as long as either a CVC or active cancer is present. If cancer goes into remission, at the time of CVC removal, anticoagulation will be stopped, but patients will continue to be followed until the end of the study at 6 months.

Primary outcomes

• Venous Thromboembolism (VTE) Rate [6 months]: The rates of symptomatic, objectively confirmed new or recurrent major VTE (proximal upper or lower extremity DVT, segmental or larger pulmonary embolism (PE)) with corresponding 95% Confidence Interval (CI) at 6 months.

Secondary outcomes

• Major Venous Thromboembolism (VTE) and Major bleeding Rate [3 months]: Rates of new/recurrent symptomatic major VTE and major bleeding at 3 months.
• New/recurrent symptomatic catheter-related upper extremity Deep Vein Thrombosis (DVT). [3 months and 6 months]: New/recurrent symptomatic catheter-related upper extremity DVT.
• New incidental Venous Thromboembolism (VTE) [3 months and 6 months]: New incidental VTE (PE or upper or lower extremity DVT), defined as VTE diagnosed on imaging studies obtained not for concern of VTE, such as cancer staging scans.
• New Deep Vein Thrombosis (DVT) [3 months and 6 months]: New/recurrent any distal upper or lower extremity DVT or subsegmental PE.
• Superficial vein thrombosis of upper or lower extremities [3 months and 6 months]: Superficial vein thrombosis of upper or lower extremities
• New unusual site Venous Thromboembolism (VTE) [3 months and 6 months]: New unusual site VTE (such as splanchnic vein, cerebral vein, or gonadal vein thrombosis).
• Clinically Relevant Non-Major Bleeding (CRNMB) events [3 months and 6 months]: CRNMB events by International Society on Thrombosis and Haemostasis (ISTH) criteria2 and composite major bleeding and CRNMB events.
• Arterial thromboembolic events [3 months and 6 months]: Arterial thromboembolic events (objectively confirmed), including myocardial infarction, stroke, peripheral arterial disease, or other systemic arterial embolism.
• All-cause mortality [3 months and 6 months]: All-cause mortality
• Correlative biomarkers [6 months]: Correlative biomarkers at 6 months, while the exact list of correlative biomarkers is to be determined at the time of study completion, examples include D-dimer, P-selectin, prothrombin F1+F2, thrombin generation, etc.
• Health-related quality of life using the EuroQoL-5D-5L Questionnaire [6 months]: Health-related quality of life using EuroQoL-5D-5L (5Dimension- mobility, self-care, usual activities, pain/discomfort, and anxiety/depression and 5L- severity levels) questionnaires on enrollment and at 6 months. EQ-5D-5L index scores range from -0.59 to 1, where 1 is the best possible health state.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

Adult patients (≥ 18 years old) with active cancer, defined as cancer (other than localized non-melanoma skin cancer) diagnosed or treated within 6 months, or the presence of metastatic, recurrent, or progressive malignancy, ongoing anticancer therapy, or hematological malignancy not in complete remission.

Objectively confirmed catheter-related upper extremity DVT and treated with any standard therapeutic anticoagulation (including LMWH dose reduction to 75% after the first month) for at least 3 months.

Able and willing to provide informed consent.

Exclusion Criteria:

Active bleeding or other reasons for which anticoagulation is contraindicated.

Other indications requiring ongoing therapeutic dose of anticoagulation as deemed necessary by treating physicians (such as atrial fibrillation, mechanical heart valve, etc.).

Anticoagulation has been permanently stopped or reduced to prophylactic dose for > 5 days prior to enrollment for any reasons.

Pregnancy or breast feeding in patients who are prescribed a direct oral anticoagulant.

Concomitant use of strong inhibitors or inducers of both cytochrome P450 3A4 and P-glycoprotein in patients who are prescribed a direct oral anticoagulant.

Cancer is in remission and CVC is removed prior to enrollment.

Requirement of dual antiplatelet therapies.

Platelet count < 50 x 109/L or creatinine clearance < 30 ml/min.

Life expectancy of less than 3 months.

• Tzu-Fei Wang, MD, MPH, Principal investigator, Ottawa Hospital Research Institute