Fondaparinux reduced the composite of death, pulmonary embolism, deep-vein thrombosis, or superficial-vein thrombosis extension/recurrence compared to placebo (0.9% vs 5.9%; P<0.001).
RCT (n=3,002)
double-blind
randomized
Does fondaparinux reduce the composite of death, pulmonary embolism, deep-vein thrombosis, extension, or recurrence in patients with acute symptomatic superficial-vein thrombosis?
Fondaparinux 2.5 mg daily for 45 days significantly reduced the risk of symptomatic VTE complications in patients with acute superficial-vein thrombosis without increasing major bleeding.
Effect estimate: Relative risk reduction 85% (95% CI 74 to 92)
Absolute Event Rate: 0.9% vs 5.9%
p-value: p=<0.001
BACKGROUND: The efficacy and safety of anticoagulant treatment for patients with acute, symptomatic superficial-vein thrombosis in the legs, but without concomitant deep-vein thrombosis or symptomatic pulmonary embolism at presentation, have not been established. METHODS: In a randomized, double-blind trial, we assigned 3002 patients to receive either fondaparinux, administered subcutaneously at a dose of 2.5 mg once daily, or placebo for 45 days. The primary efficacy outcome was a composite of death from any cause or symptomatic pulmonary embolism, symptomatic deep-vein thrombosis, or symptomatic extension to the saphenofemoral junction or symptomatic recurrence of superficial-vein thrombosis at day 47. The main safety outcome was major bleeding. The patients were followed until day 77. RESULTS: The primary efficacy outcome occurred in 13 of 1502 patients (0.9%) in the fondaparinux group and 88 of 1500 patients (5.9%) in the placebo group (relative risk reduction with fondaparinux, 85%; 95% confidence interval CI, 74 to 92; P<0.001). The incidence of each component of the primary efficacy outcome was significantly reduced in the fondaparinux group as compared with the placebo group, except for the outcome of death (0.1% in both groups). The rate of pulmonary embolism or deep-vein thrombosis was 85% lower in the fondaparinux group than in the placebo group (0.2% vs. 1.3%; 95% CI, 50 to 95; P<0.001). Similar risk reductions were observed at day 77. A total of 88 patients would need to be treated to prevent one instance of pulmonary embolism or deep-vein thrombosis. Major bleeding occurred in one patient in each group. The incidence of serious adverse events was 0.7% with fondaparinux and 1.1% with placebo. CONCLUSIONS: Fondaparinux at a dose of 2.5 mg once a day for 45 days was effective in the treatment of patients with acute, symptomatic superficial-vein thrombosis of the legs and did not have serious side effects. (Funded by GlaxoSmithKline; ClinicalTrials.gov number, NCT00443053.)
Decousus et al. (Wed,) conducted a rct in acute, symptomatic superficial-vein thrombosis in the legs (n=3,002). Fondaparinux vs. placebo was evaluated on composite of death from any cause or symptomatic pulmonary embolism, symptomatic deep-vein thrombosis, or symptomatic extension to the saphenofemoral junction or symptomatic recurrence of superficial-vein thrombosis at day 47 (Relative risk reduction 85%, 95% CI 74 to 92, p=<0.001). Fondaparinux reduced the composite of death, pulmonary embolism, deep-vein thrombosis, or superficial-vein thrombosis extension/recurrence compared to placebo (0.9% vs 5.9%; P<0.001).