SWITCH III: Bivalirudin appears safe after fondaparinux in PCI patients

Bivalirudin appears to be as safe as standard-dose unfractionated heparin in patients with acute coronary syndrome treated with fondaparinux before percutaneous coronary intervention, according to results from the SWITCH III trial.

Ron Waksman, MD, associate director of the division of cardiology at the Washington Hospital Center, and colleagues conducted the SWITCH III trial to evaluate the safety of switching from fondaparinux (Arixtra, GlaxoSmithKline) to unfractionated heparin or bivalirudin (Angiomax, The Medicines Company) in patients with non–ST-elevation ACS within 24 hours of undergoing angiography followed by possible PCI.

“In the US, we are interested in this situation because fondaparinux is not approved for ACS, and bivalirudin is highly used in the majority of cath labs,” Waksman said during a presentation. “In Europe, we are in the opposite situation where fondaparinux is being used, is approved and is in the guidelines for ACS, and bivalirudin is not used much. However, this question of switching from fondaparinux to bivalirudin has not been studied before.”

The researchers randomly assigned 100 patients prescribed fondaparinux to bivalirudin (n=51) or heparin (n=49). There were no deaths or fatal disease in either group. Two patients in the bivalirudin group and none in the heparin group experienced major bleeds as defined by SWITCH III and OASIS criteria. Additionally, no patients experienced catheter thromboses — an especially important finding, Waksman said. Results also showed similar safety between the two drugs for other outcomes, including access site complications, MI, procedural complications, the need for repeat revascularization and mortality.

Use of radial access was more common than femoral access in both groups (68.6% vs. 31% and 67.3% vs. 32%), according to study data.

Study limitations included the small number of patients, and radial access was used in two-thirds of patients. Nevertheless, Waksman said the results have important implications.

“The data from this prospective multicenter trial suggest that bivalirudin in comparison to standard-dose unfractionated heparin has a similar safety profile in terms of peri-PCI bleeding and thrombotic events,” Waksman said. “The length of intracatheter thrombus in the bivalirudin group suggests that it can be safely used in ACS patients treated with upstream fondaparinux, and we would like to replicate [these results] in large randomized trials to establish the safety and efficacy of treating patients with bivalirudin in this setting.” – by Melissa Foster

For more information:

Waksman R. iMPACT trial — SWITCH III: Switching from fondaparinux to bivalirudin in ACS patients. Presented at: the Cardiovascular Research Technologies 2012; Feb. 4-7, 2012; Washington.

Follow HemOncToday.com on Twitter.