Alerts and Actions
May 2005
FDA announces new warning label changes for fondaparinux (Arixtra®)
Medication Safety Actions:
Pre-printed order forms, care maps and computer decision support rules should be modified to include the above safety information.
New Contraindications
Prophylactic therapy is now contraindicated in patients with body weight <50 kg undergoing hip fracture, hip replacement or knee replacement surgery, and abdominal surgery. During the randomized clinical trials of prophylaxis in the peri-operative period following hip fracture, hip replacement, or knee replacement surgery, occurrence of major bleeding was doubled in patients with a body weight <50 kg compared with those with a body weight >=50 kg (5.4% versus 2.1%). In the clinical trial in patients undergoing abdominal surgery, the major bleeding rate was also higher in patients with a body weight <50 kg as compared to those with a body weight >=50 kg (5.3% versus 3.3%), respectively.
In addition to the new contraindications, warnings for increased major bleeding in patients with mild to severe renal impairment prescribed the usual dose have been added.
Major bleeding in patients receiving prophylactic therapy in abdominal surgery occurred in 2.1% (13/606) of patients with normal renal function, in 3.6% (22/613) with mild renal impairment, in 6.7% (12/179) with moderate renal impairment, and in 7.1% (1/14) with severe renal impairment. When Arixtra was used according to the recommended timing of the first injection (6 to 8 hours after surgery), major bleeding occurred in 2.1% (10/467) of patients with normal renal function, in 3.3% (16/481) with mild renal impairment, in 5.8% (8/137) with moderate renal impairment, and in 7.7% (1/13) with severe renal impairment.