Blood Thinners for Cancer

(VENO CAT Trial)

Age: Any Age

Sex: Any

Trial Phase: Academic

Sponsor: University Health Network, Toronto

Must be taking: DOACs

Must not be taking: Strong inhibitors, inducers

Disqualifiers: Low creatinine, recent VTE, low platelets, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 2

Duration: 1 day

10 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial will compare continuing versus stopping blood thinners (DOACs) for people with cancer undergoing certain procedures. It doesn't specify if you need to stop other medications, so it's best to ask the trial team for guidance.

What data supports the effectiveness of the drug for cancer patients?

Research shows that direct oral anticoagulants (DOACs) are effective in reducing the risk of blood clots in cancer patients, with studies indicating a significant decrease in venous thromboembolism (VTE) events. They are also considered a safe alternative to other blood thinners like enoxaparin, with fewer bleeding events reported. ^{1 2 3 4 5}

Are blood thinners safe for cancer patients?

Research suggests that direct oral anticoagulants (DOACs), a type of blood thinner, are generally safe for cancer patients, with no significant increase in major bleeding risks compared to traditional treatments. However, there is a potential risk of minor bleeding, and more studies are needed to confirm these findings. ^{1 4 6 7 8}

How do DOACs differ from other drugs for cancer-associated thrombosis?

DOACs (direct oral anticoagulants) are unique because they are taken orally and have potential anti-tumor effects in addition to preventing blood clots, unlike traditional treatments that are often injected and focus solely on clot prevention. ^{2 3 9 10 11}

What is the purpose of this trial?

The peri-procedural management of direct oral anticoagulants (DOACs) in persons with cancer (PWC) undergoing tunneled or port central venous catheter (CVC) insertion is a common but understudied clinical problem, with conflicting management advice from guidelines and resultant uncertainty for best practices. Data from prospective studies assessing peri-procedural DOAC management exist; however, these data pertain to procedures in the general population. These management strategies may not be applicable to PWC because (1) although CVC insertion is a low risk, image-guided specialized procedure, (2) PWC are at considerably higher risk of peri-procedural bleeding and thrombosis than non-PWC. It is not surprising, therefore, that guideline recommendations and current practices vary widely. To resolve management uncertainty and establish a standard-of-care, the VENOCAT pilot randomized controlled trial (RCT) is a first step that will assess the feasibility of a definitive trial comparing continued vs. interrupted DOAC management in PWC undergoing tunneled or port CVC insertion. Evidence is needed to standardize clinical practice and reduce the risk of bleeding and thrombotic complications.

Eligibility Criteria

This trial is for cancer patients who need a central venous catheter and have either blood clots or atrial fibrillation. They must be taking direct oral anticoagulants (DOACs). Specific eligibility criteria are not provided, but typically include factors like age, overall health, and the type of cancer.

Inclusion Criteria

I am an adult taking blood thinners for blood clots or irregular heartbeat.

I am willing and able to follow the blood thinner plan and check-ups.

My cancer is active, advanced, or treated recently.

Exclusion Criteria

Platelet count < 50 x 10^9/L at time of study entry

I was diagnosed with a blood clot less than 3 weeks ago.

My kidney function is low, not meeting the threshold for certain blood thinners.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants are randomized to either continue or interrupt DOAC management peri-procedurally during CVC insertion

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after the procedure, including assessment of bleeding and thrombotic events

30 days

1 visit (in-person)

Treatment Details

Interventions

• Continued DOAC
• Interrupted DOAC

Trial Overview The VENOCAT pilot study is testing whether it's better to continue or interrupt DOAC therapy when these patients undergo catheter placement. It aims to find out which approach reduces the risk of bleeding and clotting without causing other problems.

Participant Groups

Group I: Continued DOAC Experimental Treatment 1 Intervention

The continued DOAC group will continue their DOAC peri-procedurally as routine without interruption. This management strategy was devised based on the cardiac device insertion studies which found continued AC to be a safe and efficacious strategy for cardiac device insertion, which is procedurally similar to tunneled or port CVC insertion. This is the peri-procedural AC strategy for tunneled or port CVC insertion suggested by the Society of Interventional Radiology guidelines.

Group II: Interrupted DOAC Active Control 1 Intervention

The interrupted DOAC group will take their last DOAC dose on Day -2, unless their DOAC is Dabigatran and their creatinine clearance is \< 50mL/min (Cockcroft-Gault equation), in which their last dose will be on Day -3. The DOAC will be resumed on Day +1. This management strategy was utilized in the PAUSE study and was devised taking into account DOAC half-lives, manufacturer recommendations, and available literature. With this strategy, DOACs would be interrupted for three to four halflives, resulting in minimal residual anticoagulant effect. DOAC interruption is described by number of days rather than hours to allow for a simple pragmatic strategy that would be easy to apply in practice and follow by patients. This strategy was found to be safe and efficacious in the PAUSE and cardiac device insertion studies. This is the peri-procedural AC strategy for tunneled or port CVC insertion suggested by the ISTH.

Who Is Running the Clinical Trial?

University Health Network, Toronto

Lead Sponsor

Trials

1,555

Recruited

526,000+

Helliwell Foundation

Collaborator

Trials

1

Recruited

10+

References

1. England pubmed.ncbi.nlm.nih.gov

Characteristics and outcomes of patients on concurrent direct oral anticoagulants and targeted anticancer therapies-TacDOAC registry: Communication from the ISTH SSC Subcommittee on Hemostasis and Malignancy. [2023]

2. United States pubmed.ncbi.nlm.nih.gov

A systematic review on the effects of direct oral anticoagulants on cancer growth and metastasis in animal models. [2021]

3. United States pubmed.ncbi.nlm.nih.gov

Rivaroxaban vs Dalteparin in Cancer-Associated Thromboembolism: A Randomized Trial. [2022]

4. England pubmed.ncbi.nlm.nih.gov

Direct oral anticoagulants for thromboprophylaxis in ambulatory patients with cancer. [2020]

5. Netherlands pubmed.ncbi.nlm.nih.gov

Anticoagulation prescribing patterns in patients with cancer. [2018]

6. Netherlands pubmed.ncbi.nlm.nih.gov

Evaluation of direct oral anticoagulants for the treatment of venous thromboembolism in the oncology population. [2018]

7. Germany pubmed.ncbi.nlm.nih.gov

Direct oral anticoagulants for venous thromboembolism in cancer patients: a systematic review and network meta-analysis. [2023]

8. Switzerland pubmed.ncbi.nlm.nih.gov

Efficacy and Safety of Direct Oral Anticoagulants for Secondary Prevention of Cancer-Associated Thrombosis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials and Prospective Cohort Studies. [2023]

9. Greece pubmed.ncbi.nlm.nih.gov

Direct Oral Anticoagulants for the Treatment of Venous Thromboembolism in Patients With Active Cancer. [2021]

10. United States pubmed.ncbi.nlm.nih.gov

Direct Oral Anticoagulants and Cancer-Associated Thrombosis Management. Where Do We Stand in 2019? [2020]

11. England pubmed.ncbi.nlm.nih.gov

Clot regression effects of rivaroxaban in the treatment of venous thromboembolism in patients with cancer (CRERIT-VTE cancer): study protocol. [2020]