Silence Therapeutics shares rose sharply after the company reported positive topline results from its Phase 2 SANRECO trial of divesiran in polycythemia vera, a rare blood cancer marked by excess red blood cell production that can increase the risk of clots, heart attacks and strokes. In the 36-week study, 88% of divesiran-treated patients met the primary endpoint of avoiding phlebotomies while keeping hematocrit below 45% between weeks 18 and 36, compared with 19% of placebo recipients. Response rates were 93.8% with dosing every six weeks and 81.3% with quarterly dosing, producing a placebo-adjusted response rate of 69%. The study also met key secondary endpoints, with divesiran-treated patients averaging 0.2 phlebotomies versus 2.1 in the placebo arm, alongside improvements in hematocrit control, iron ferritin markers and symptoms measured by the MPN-SAF Total Symptom Score. Silence said divesiran, a first-in-class short interfering RNA therapy, was well tolerated, with no new safety signals, infrequent self-limiting injection site reactions and two investigator-reported grade 1 anemia adverse events. Chief Medical Officer Curtis Rambaran said the trial confirmed Phase 1 findings with dosing every six weeks and showed similarly durable effects with dosing every 12 weeks. Silence expects to start a Phase 3 trial of 12-week divesiran dosing versus placebo in the first half of 2027 and reported cash of $72.1 million as of June 30, 2026.