The primary objective was to compare the efficacy of once daily [q.d] subcutaneous [s.c.] injections of Semuloparin sodium (AVE5026) with q.d. s.c. injections of Enoxaparin for the primary prevention of Venous Thromboembolic Events [VTE] in patients hospitalized for acute medical illness.

The secondary objectives were to evaluate the safety of AVE5026 and to document AVE5026 exposure in this population.

Randomization had to take place just prior to the first study drug injection.

The total duration of observation per participant was 35-42 days from randomization broken down as follows:

• 10 to 14-day double-blind treatment period;
• 25 to 32-day follow-up period.

Mandatory bilateral compression ultrasound [CUS] had to be performed between 10 to 15 days after randomization.

Inclusion Criteria:

Patient with an acute medical condition requiring bed rest for at least 3 days, and hospitalized for at least one of the following medical conditions:

• Congestive heart failure (New York Heart Association [NYHA] class III/IV);

• Acute respiratory failure (not requiring mechanical ventilation);

• Acute infection (without septic shock)*;

• Acute rheumatic disorder*;

• Acute episode of inflammatory bowel disease*.

  • Patient with one of these conditions should have at least one additional risk factor for venous thromboembolism (VTE) among the following:

    • Age ≥ 75 years;
    • Active cancer or myeloproliferative disorders (having received treatment for cancer within the last 6 months);
    • Previous VTE;
    • Obesity;
    • Oral hormone therapy (antiandrogen or estrogen);
    • Chronic heart failure;
    • Chronic respiratory failure.

Exclusion Criteria:

• Previous surgery with general anesthesia within 30 days before inclusion in the study;
• Patient requiring a curative anticoagulant or thrombolytic treatment;
• Patient at risk of bleeding;
• Stroke;
• Known hypersensitivity to heparin or enoxaparin sodium;
• End stage renal disease or patient on dialysis.

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.