Nature Biotechnology pp 1423 - 1428

Anticoagulant drugs, such as streptokinase and tissue plasminogen activator (tPA), are widely used to treat and prevent blood clots, but they carry a risk of causing serious hemorrhage. In the November issue of Nature Biotechnology, Bruce Sullenger and colleagues report that an unconventional drug, comprising the nucleic acid RNA, is efficacious in animals as an anticoagulant. What's more, it comes with its own antidote (an RNA complement that binds and neutralizes the drug), allowing better control of anticoagulant activity, which may be important in settings such as the surgical operating theatre where anticoagulants are often needed.

The drug and the antidote were shown to work in clinically predictive models of cardiovascular disease in both pigs and mice. In addition, the antidote prevented hemorrhage in the clipped tails of mice that had received the anticoagulant, demonstrating the efficacy of the antidote in a surgical trauma model.