AHA: Novel Anticoagulant Drug, Antidote Promising in Phase 1
RNA aptamer-based technology that targets factor IXa was tested in 85 patients
TUESDAY, Nov. 14 (HealthDay News) -- A novel anticoagulant system that relies on a shape-changing RNA aptamer and its fast-acting antidote has been tested for the first time in patients, according to a report presented at the American Heart Association's Scientific Sessions and simultaneously published in Circulation: Journal of the American Heart Association. The drug platform, known as REG1, could have applications for oncology, rheumatic disease or infections and seemed safe. However, one patient did experience transient encephalopathy that may or may not have been therapy-related, reported Richard Becker, M.D., of Duke University in Durham, N.C.
Christopher Dyke, M.D., Becker and colleagues randomized 85 healthy volunteers to receive an intravenous infusion of RB006, an oligonucleotide that binds to factor IXa, or a placebo. An escalating drug-dosage design was used, with 15, 30, 60 and 90 mg of the drug. The antidote, RB007, was administered at a 2:1 ratio three hours later.
Patients treated with 15 mg of the drug had a 1.1-fold increase in activated partial thromboplastin time (APTT) 15 minutes after administration, while those given higher doses had a more pronounced response (2.9-fold increase in mean relative APTT at 15 minutes with 90 mg dose). The antidote returned the APTT to baseline within one to five minutes.
"The drug-antidote system as we describe here could be used as a potential replacement for heparin," said Becker. Aptamers "are able to fold and they assume shapes that are directed against a target," he notes. While the current platform targets factor IXa, the use of other targets could make the drug-antidote system useful in oncology and other diseases, he said.
The study was funded by Regado Biosciences, Inc., of Durham, N.C.