1. SANOFI-SYNTHELABOARIXTRA ® 1 ARIXTRA ® (fondaparinux sodium) in the prevention of venous thromboembolism after major knee surgery KA Bauer, BI Eriksson, MR Lassen, and AGG Turpie on behalf of the Steering Committees of the Pentasaccharide Orthopaedic Prophylaxis Studies PENTAMAKS

2. SANOFI-SYNTHELABOARIXTRA2 PENTAMAKS: OBJECTIVE AND DESIGN  To compare the efficacy and safety of s.c. injections of Arixtra ® 2.5 mg o.d. with enoxaparin 30 mg b.i.d. in preventing venous thromboembolism (VTE) in patients undergoing elective major knee surgery.  A multicenter, randomized, double-blind, two-parallel-group comparative trial in 1049 patients.

3. SANOFI-SYNTHELABOARIXTRA3 PENTAMAKS: DESIGN Arixtra ® 2.5 mg o.d. Enoxaparin 30 mg b.i.d. start post-op start 6 ± 2 hrs post-op Venogram Day 5–11 Follow up Day 42 ± 7 Treatment 7 ± 2 Days R

4. SANOFI-SYNTHELABOARIXTRA ® 4 PENTAMAKS: ENDPOINTS  Primary efficacy: VTE up to day 11  deep-vein thrombosis (DVT) detected by mandatory bilateral venography, or  documented symptomatic DVT, or  pulmonary embolism.  Primary safety: Major bleeding.

5. SANOFI-SYNTHELABOARIXTRA5 PENTAMAKS: EFFICACY RESULTS  724 (69.0%) patients included in the primary efficacy analysis  Arixtra ® also reduced the incidence of:  any DVT by 54.1% (p<0.001),  any proximal DVT by 54.5% (p=0.06)  distal-only DVT by 55.9% (p<0.001).

6. SANOFI-SYNTHELABOARIXTRA ® 6 Arixtra ® N=517 n (%) Enoxaparin N=517 n (%) Fatal bleeding00 Bleeding in critical organ00 Bleeding leading to reoperation2 (0.4)1 (0.2) Bleeding with a bleeding index*  2 9 (1.7)0 PENTAMAKS: SAFETY RESULTS *The bleeding index was calculated as follows: [number of units of packed red blood cells or whole blood transfused] + [(pre-bleeding) - (post-bleeding) hemoglobin (g/dl) values].

7. SANOFI-SYNTHELABOARIXTRA ® 7 PENTAMAKS: CONCLUSION In patients undergoing elective major knee surgery, Arixtra ® was significantly more effective than enoxaparin in preventing VTE without increasing the risk of clinically important bleeding.