Suzhou Ribo Life Science and subsidiary Ribocure Pharmaceuticals have reported positive Phase 2a data for vortosiran, an siRNA therapy targeting coagulation Factor XI.
The study was conducted in Europe in patients with chronic coronary artery disease. Ribo said the randomised, double-blind, placebo-controlled study evaluated vortosiran in patients receiving standard-of-care aspirin therapy.
Vortosiran, also known as RBD4059, is designed to reduce Factor XI activity through RNA interference. Factor XI has become an important target in thrombosis research because it may allow reduction of thrombotic risk while potentially avoiding some bleeding limitations associated with broader anticoagulation.
The Phase 2a study showed that vortosiran was generally well tolerated and achieved profound, dose-dependent and long-lasting suppression of Factor XI activity. Patients in the trial had chronic coronary artery disease with previous myocardial infarction and were receiving aspirin.
This is relevant because patients with coronary artery disease remain at risk of recurrent thrombotic events despite standard antiplatelet therapy. A long-acting siRNA approach could offer a differentiated preventive strategy if later trials show clinical benefit and an acceptable safety profile.
Ribo said the data were presented at the China Pharmaceutical Innovation Conference in Shanghai. The company is advancing vortosiran as part of its RNA therapeutics pipeline, with subsidiary Ribocure supporting development from Sweden.
The company has initiated an ORBIT-XI development strategy that includes multiple Phase 2b studies intended to move vortosiran toward broader late-stage development across thrombotic disease settings.
