March 26th, 2012
Rivaroxaban Found Safe and Effective for Pulmonary Embolism
Larry Husten, PHD
In recent years rivaroxaban has been found to be effective in the prevention of venous thromboembolism (VTE) after orthopedic surgery, for the prevention of stroke in AF patients, and as additional therapy to conventional antiplatelet therapy in ACS patients. Now, a study presented at the American College of Cardiology meeting in Chicago and published simultaneously in the New England Journal of Medicine offers strong evidence that rivaroxaban is equally effective as standard therapy for the treatment of pulmonary embolism and may cause fewer bleeding complications.
EINSTEIN-PE was a randomized, open-label, non-inferiority study comparing rivaroxaban to conventional therapy with enoxaparin and a vitamin K antagonist in 4,832 patients with pulmonary embolism. Rivaroxaban met the predefined margin for noninferiority to conventional treatment with respect to both clinical efficacy and safety.
Primary efficacy endpoint (first symptomatic recurrent VTE):
- 2.1% for rivaroxaban patients versus 1.8% for standard therapy (HR, 1.12; 95% CI, 0.75-1.68; P=0.003 for noninferiority)
Principal safety outcome (major or clinically relevant bleeding):
- 10.3% versus 11.4% (HR, 0.90; 95% CI, 0.76-1.07; P=0.23 for noninferiority) for rivaroxaban and standard therapy, respectively
Major bleeding was significantly lower in the rivaroxaban group:
- 1.1% versus 2.2% (HR, 0.49; P=0.003) for rivaroxaban and standard therapy, respectively
Net clinical benefit (VTE plus major bleeding):
- 3.4% versus 4.0% (HR, 0.85; 95% CI, 0.63-1.14; P=0.28) for rivaroxaban and standard therapy, respectively
“Physicians want to know about major bleeding, the most important safety outcome, and rivaroxaban was highly significantly superior. This was our most astonishing finding,” said EINSTEIN chair Harry Buller in an ACC press release. “Rivaroxaban is just as good as standard treatment for PE – these data are pretty convincing – and this is an oral-only approach, which makes it very simple. The subcutaneous injections can be hazardous as well.”
The EINSTEIN investigators concluded that, in conjunction with the earlier EINSTEIN trial in DVT, the EINSTEIN PE trial supports “the use of rivaroxaban as a single oral agent for patients with venous thromboembolism.”