A Study to Evaluate the Efficacy and Safety of Fondaparinux Sodium When Used With Intermittent Pneumatic Compression to Prevent Venous Thromboembolic (IPC) Versus IPC Alone for the Prevention of Venous Thromboembolic Events in Subjects at Increased Risk Undergoing Major Abdominal Surgery (APOLLO).

This is a multicenter, randomized, double-blind, placebo-controlled study evaluating the safety and efficacy of fondaparinux in the prevention of venous thromboembolism (VTE) in subjects undergoing abdominal surgery at increased risk for VTE. During this study all subjects were to receive background VTE prophylaxis with intermittent pnuematic compression (IPC) ± elastic stockings (ES).

Screening Period ( Day -30-Day 0) all subjects at increased risk of VTE undergoing abdominal surgery and fulfilled the study entry criteria were eligible for the study.

Treatment Period (Day 7 ±2): At the baseline assessment on the day of surgery (Day 1) subjects who satisfied all inclusion/exclusion criteria were randomized (1:1) to receive either fondaparinux or placebo. All the subjects were to receive background therapy with IPC ±ES. The first administration of either fondaparinux 2.5mg or placebo was to take place 6 to 8 hours after surgical closure provided hemostasis was achieved. Thereafter a once daily subcutaneous injection of either fondaparinux 2.5mg or placebo was to be administered up to Day 7 ±2. During the treatment phase, subjects were assessed daily. A mandatory venogram was performed between Day 5 and 10 or earlier in the case of symptomatic VTE, but not more than 1 calendar day after the last study treatment administration.

Follow up Period (Day 30 ±2): A follow-up visit or contact was to take place at Day 30 ±2 days. Use of antithrombotic therapy for prevention of VTE after the mandatory venographyand during the entire Follow-up Period was left to the investigator's discretion.