Semuloparin for Thromboprophylaxis in Patients Receiving Chemotherapy for Cancer

Study Questions:

What is the efficacy and safety of semuloparin for prophylaxis against venous thromboembolism in patients receiving chemotherapy for solid tumors?

Methods:

In this double-blind, multicenter trial, the investigators evaluated the efficacy and safety of the ultra-low-molecular-weight heparin semuloparin for prevention of venous thromboembolism in patients receiving chemotherapy for cancer. Patients with metastatic or locally advanced solid tumors who were beginning to receive a course of chemotherapy were randomly assigned to receive subcutaneous semuloparin, 20 mg once daily, or placebo until there was a change of chemotherapy regimen. The primary efficacy outcome was the composite of any symptomatic deep-vein thrombosis, any nonfatal pulmonary embolism, and death related to venous thromboembolism. Clinically relevant bleeding (major and nonmajor) was the main safety outcome.

Results:

The median treatment duration was 3.5 months. Venous thromboembolism occurred in 20 of 1,608 patients (1.2%) receiving semuloparin, as compared with 55 of 1,604 (3.4%) receiving placebo (hazard ratio [HR], 0.36; 95% confidence interval [CI], 0.21-0.60; p < 0.001), with consistent efficacy among subgroups defined according to the origin and stage of cancer and the baseline risk of venous thromboembolism. The incidence of clinically relevant bleeding was 2.8% and 2.0% in the semuloparin and placebo groups, respectively (HR, 1.40; 95% CI, 0.89-2.21). Major bleeding occurred in 19 of 1,589 patients (1.2%) receiving semuloparin and 18 of 1,583 (1.1%) receiving placebo (HR, 1.05; 95% CI, 0.55-1.99). Incidences of all other adverse events were similar in the two study groups.

Conclusions:

The authors concluded that semuloparin reduces the incidence of thromboembolic events in patients receiving chemotherapy for cancer, with no apparent increase in major bleeding.

Perspective:

This study suggests that thromboprophylaxis with the ultra-low-molecular-weight heparin semuloparin, as compared with placebo, reduces the risk of venous thromboembolism among patients receiving chemotherapy for cancer, with no apparent increase in the incidence of major bleeding. The treatment effect was consistent in subgroups defined by the primary site and stage of cancer and the baseline risk of venous thromboembolism. Additional studies are indicated to answer which patients with cancer (i.e., the type and stage of cancer) would receive the most benefit, what is the true magnitude of the benefit, and is there a benefit for cancers that respond poorly to other therapies?

Keywords: Incidence, Neoplasms, Heparin, Low-Molecular-Weight, Pulmonary Embolism, Venous Thromboembolism, Venous Thrombosis, Confidence Intervals, Embolism


< Back to Listings