An experimental medicine from Silence Therapeutics stabilized red blood cell levels in patients with a rare blood cancer in a new trial — a result that could position it to compete with a drug from Takeda Pharmaceuticals that is nearing approval.

The cancer, polycythemia vera, is marked by runaway production of red blood cells and puts patients at risk of life-threatening blood clots, bleeds, and other cancers. 

In the 48-person, Phase 2 trial, 88% of patients who received Silence’s drug, called divesiran, every six weeks or 12 weeks achieved a clinical response, the company said Monday. By contrast, only 19% of patients on placebo did.