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

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to determine the best way to manage blood thinners for cancer patients undergoing the insertion of a special catheter (a small tube). It will compare two strategies: continuing the blood thinner (DOAC, a type of anticoagulant) or pausing it before the procedure. The goal is to reduce the risk of bleeding and clotting problems during and after the procedure. Suitable participants have active cancer and are already on blood thinners for conditions like blood clots or an irregular heartbeat. As an unphased trial, this study provides patients the opportunity to contribute to important research that could enhance care for others in similar situations.

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.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that direct oral anticoagulants (DOACs) are generally safe for cancer patients. Studies have found that patients using DOACs have a lower risk of serious bleeding and recurrent blood clots compared to those using other blood thinners. For instance, one study found that people taking DOACs had a lower risk of dying from any cause than those on other treatments. DOACs are sometimes stopped temporarily before certain procedures, such as inserting a central venous catheter, and this has been done safely in similar situations. Some studies noted a small number of patients experienced bleeding or clotting after stopping DOACs, but these rates were similar to other treatments. Overall, both continuous and temporary DOAC treatments have been well-tolerated, but discussing individual risks with a healthcare provider is important. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores two different approaches to managing blood thinners, or DOACs, for cancer patients undergoing procedures. The "Interrupted DOAC" strategy involves temporarily stopping the blood thinner, which may reduce bleeding risks during surgery while maintaining safety and effectiveness, as shown in previous studies. The "Continued DOAC" strategy, on the other hand, keeps the blood thinner going without interruption, potentially simplifying the process and aligning with interventional radiology guidelines. This trial aims to determine which method is safer and more effective, potentially leading to better outcomes for patients needing central venous catheter insertions.

What evidence suggests that this trial's treatments could be effective for cancer patients undergoing CVC insertion?

Research has shown that direct oral anticoagulants (DOACs) can reduce the risk of blood clots and death in cancer patients. One study found that patients taking DOACs had a lower risk of serious bleeding and lived longer compared to those using traditional blood thinners. Another study confirmed that DOACs are both effective and safe for people with cancer.

In this trial, participants will join one of two groups: the Continued DOAC group or the Interrupted DOAC group. The Continued DOAC group will maintain their DOAC regimen peri-procedurally without interruption. Meanwhile, the Interrupted DOAC group will temporarily stop their DOACs before medical procedures. Studies have shown that briefly pausing DOACs before surgery can safely manage bleeding risks while still protecting against clots. This method has proven effective and safe for cancer patients. ^{2 3 5 6 7}

Are You a Good Fit for This Trial?

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 for a Trial Participant

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)

What Are the Treatments Tested in This Trial?

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.

How Is the Trial Designed?

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+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12418083/

Comparative Effectiveness of Direct Oral Anticoagulants ... This study provides insight into the effectiveness of DOACs compared to warfarin for VTE in cancer patients. Patients on DOACs had lower risks ...

2. jamanetwork.com jamanetwork.com/journals/jamanetworkopen/fullarticle/2807546

Comparative Effectiveness of Anticoagulants in Patients ... In this study, DOACs were associated with a higher persistence rate, lower risk of VTE recurrence, lower risk of major bleeding, and improved mortality.

3. sciencedirect.com sciencedirect.com/science/article/pii/S247503792500202X

Evaluation of extended direct oral anticoagulant dosing ... This study examined the effectiveness, safety, and utilization of low dose DOACs in a real-world cohort with dedicated analysis of cancer patients.

4. onlinelibrary.wiley.com onlinelibrary.wiley.com/doi/10.1002/ajh.70090

A Systematic Review and Meta‐Analysis of Randomized ... As highlighted by our meta-analysis, the results of these trials now strengthen the evidence that reduced-dose DOAC is likely as efficacious as ...

5. ahajournals.org ahajournals.org/doi/10.1161/CIRCOUTCOMES.122.008951

Comparative Effectiveness and Safety of Direct Oral ... DOAC users had significantly lower risk of all-cause death (7.09 versus 13.3 per 100 person-years, adjusted hazard ratio 0.81 [95% CI, 0.69–0.94]) ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11229502/

Effectiveness and safety of continuous low-molecular-weight ... In conclusion, compared with the continuous use of LMWH, switching to DOACs was associated with a lower risk of hospitalization due to VTE and ...

7. ashpublications.org ashpublications.org/blood/article/144/Supplement%201/5086/533563/Clinical-Outcomes-of-Cancer-Associated-Venous

Clinical Outcomes of Cancer-Associated Venous ... In this study, gastrointestinal or genitourinary cancer patients treated for VTE had similar bleeding and VTE recurrence rates when treated with a DOAC or LMWH.