Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The adverse reaction information below is based on data from 8,877 patients exposed to fondaparinux sodium in controlled trials of hip fracture, hip replacement, major knee, or abdominal surgeries, and DVT and PE treatment.
Hemorrhage
During administration of fondaparinux sodium, the most common adverse reactions were bleeding complications [see Warnings and Precautions (5.2)].
Hip Fracture, Hip Replacement, and Knee Replacement Surgery
The rates of major bleeding events reported during 3 active-controlled peri-operative VTE prophylaxis trials with enoxaparin sodium in hip fracture, hip replacement, or knee replacement surgery (N = 3,616) and in an extended VTE prophylaxis trial (n = 327) with fondaparinux sodium 2.5 mg are provided in Table 2.
Table 2. Bleeding Across Randomized, Controlled Hip Fracture, Hip Replacement, and Knee Replacement Surgery Studies
a Enoxaparin sodium dosing regimen: 30 mg every 12 hours or 40 mg once daily. b Not approved for use in patients undergoing hip fracture surgery. c Major bleeding was defined as clinically overt bleeding that was (1) fatal, (2) bleeding at critical site (e.g. intracranial, retroperitoneal, intraocular, pericardial, spinal, or into adrenal gland), (3) associated with re-operation at operative site, or (4) with a bleeding index (BI) ≥2. d BI ≥2: Overt bleeding associated only with a bleeding index (BI) ≥2 calculated as [number of whole blood or packed red blood cell units transfused + [(pre-bleeding) – (post-bleeding)] hemoglobin (g/dL) values]. e Minor bleeding was defined as clinically overt bleeding that was not major.
|
| Peri-Operative Prophylaxis (Day 1 to Day 7 ± 1 post-surgery)
| Extended Prophylaxis (Day 8 to Day 28 ± 2 post-surgery)
|
Fondaparinux Sodium 2.5 mg SC once daily N = 3,616
| Enoxaparin Sodiuma, b N = 3,956
| Fondaparinux Sodium 2.5 mg SC once daily N = 327
| Placebo SC once daily N = 329
|
Major bleedingc
| 96 (2.7%)
| 75 (1.9%)
| 8 (2.4%)
| 2 (0.6%)
|
Hip fracture
| 18/831 (2.2%)
| 19/842 (2.3%)
| 8/327 (2.4%)
| 2/329 (0.6%)
|
Hip replacement
| 67/2,268 (3.0%)
| 55/2,597 (2.1%)
| —
| —
|
Knee replacement
| 11/517 (2.1%)
| 1/517 (0.2%)
| —
| —
|
Fatal bleeding
| 0 (0.0%)
| 1 (<0.1%)
| 0 (0.0%)
| 0 (0.0%)
|
Non-fatal bleeding at critical site
| 0 (0.0%)
| 1 (<0.1%)
| 0 (0.0%)
| 0 (0.0%)
|
Re-operation due to bleeding
| 12 (0.3%)
| 10 (0.3%)
| 2 (0.6%)
| 2 (0.6%)
|
BI ≥2d
| 84 (2.3%)
| 63 (1.6%)
| 6 (1.8%)
| 0 (0.0%)
|
Minor bleedinge
| 109 (3.0%)
| 116 (2.9%)
| 5 (1.5%)
| 2 (0.6%)
|
A separate analysis of major bleeding across all randomized, controlled, peri-operative, prophylaxis clinical studies of hip fracture, hip replacement, or knee replacement surgery according to the time of the first injection of fondaparinux sodium after surgical closure was performed in patients who received fondaparinux sodium only post-operatively. In this analysis, the incidences of major bleeding were as follows: <4 hours was 4.8% (5/104), 4 to 6 hours was 2.3% (28/1,196), 6 to 8 hours was 1.9% (38/1,965). In all studies, the majority (≥75%) of the major bleeding events occurred during the first 4 days after surgery.
Abdominal Surgery
In a randomized study of patients undergoing abdominal surgery, fondaparinux sodium 2.5 mg once daily (n = 1,433) was compared with dalteparin 5,000 IU once daily (n = 1,425). Bleeding rates are shown in Table 3.
Table 3. Bleeding in the Abdominal Surgery Study
a Major bleeding was defined as bleeding that was (1) fatal, (2) bleeding at the surgical site leading to intervention, (3) non-surgical bleeding at a critical site (e.g. intracranial, retroperitoneal, intraocular, pericardial, spinal, or into adrenal gland), or leading to an intervention, and/or with a bleeding index (BI) ≥2. b Minor bleeding was defined as clinically overt bleeding that was not major.
|
| Fondaparinux Sodium 2.5 mg SC once daily
| Dalteparin Sodium 5,000 IU SC once daily
|
N = 1,433
| N = 1,425
|
Major bleedinga
| 49 (3.4%)
| 34 (2.4%)
|
Fatal bleeding
| 2 (0.1%)
| 2 (0.1%)
|
Non-fatal bleeding at critical site
| 0 (0.0%)
| 0 (0.0%)
|
Other non-fatal major bleeding Surgical site Non-surgical site
| 38 (2.7%) 9 (0.6%)
| 26 (1.8%) 6 (0.4%)
|
Minor bleedingb
| 31 (2.2%)
| 23 (1.6%)
|
The rates of major bleeding according to the time interval following the first fondaparinux sodium injection were as follows: <6 hours was 3.4% (9/263) and 6 to 8 hours was 2.9% (32/1112).
Treatment of Deep Vein Thrombosis and Pulmonary Embolism
The rates of bleeding events reported during a dose-response trial (n = 111) and an active-controlled trial with enoxaparin sodium in DVT treatment (n = 1,091) and an active-controlled trial with heparin in PE treatment (n = 1,092) with fondaparinux sodium are provided in Table 4.
Table 4. Bleedinga in Deep Vein Thrombosis and Pulmonary Embolism Treatment Studies
a Bleeding rates are during the study drug treatment period (approximately 7 days). Patients were also treated with vitamin K antagonists initiated within 72 hours after the first study drug administration. b Major bleeding was defined as clinically overt: –and/or contributing to death – and/or in a critical organ including intracranial, retroperitoneal, intraocular, spinal, pericardial, or adrenal gland – and/or associated with a fall in hemoglobin level ≥2 g/dL – and/or leading to a transfusion ≥2 units of packed red blood cells or whole blood. c Clinically overt bleeding with a 2 g/dL fall in hemoglobin and/or leading to transfusion of PRBC or whole blood ≥2 units. d Minor bleeding was defined as clinically overt bleeding that was not major.
|
| Fondaparinux Sodium N = 2,294
| Enoxaparin Sodium N = 1,101
| Heparin aPTT adjusted intravenous N = 1,092
|
Major bleedingb
| 28 (1.2%)
| 13 (1.2%)
| 12 (1.1%)
|
Fatal bleeding
| 3 (0.1%)
| 0 (0.0%)
| 1 (0.1%)
|
Non-fatal bleeding at a critical site
| 3 (0.1%)
| 0 (0.0%)
| 2 (0.2%)
|
Intracranial bleeding
| 3 (0.1%)
| 0 (0.0%)
| 1 (0.1%)
|
Retro-peritoneal bleeding
| 0 (0.0%)
| 0 (0.0%)
| 1 (0.1%)
|
Other clinically overt bleedingc
| 22 (1.0%)
| 13 (1.2%)
| 10 (0.9%)
|
Minor bleedingd
| 70 (3.1%)
| 33 (3.0%)
| 57 (5.2%)
|