Silence Therapeutics (NASDAQ: SLN) Announced Positive Topline Results From the Phase 2 SANRECO Trial of Divesiran, a First-in-Class TMPRSS6-Targeting siRNA That Increases Hepcidin Production to Restrict Iron Availability to Bone Marrow and Reduce Excessive Red Blood Cell Production in Polycythemia Vera (PV); Trial Enrolled 48 Phlebotomy-Dependent PV Patients With Divesiran 6 mg/kg Administered Subcutaneously Every 6 Weeks or Every 12 Weeks; 88% of Divesiran-Treated Patients Achieved a Response Versus 19% on Placebo (P<0.0001), Corresponding to a 69% Placebo-Adjusted Response Rate; Divesiran Has FDA Fast Track and Orphan Drug Designations for PV; Company Anticipates Initiating a Phase 3 Trial Evaluating Divesiran Every 12 Weeks Versus Placebo in H1 2027 Extending the Broader siRNA Cardiometabolic and Rare-Disease Franchise Landscape That Also Includes Alnylam's Amvuttra and Arrowhead's Redemplo (Plozasiran)
Silence Therapeutics (NASDAQ: SLN) announced positive topline results from the Phase 2 SANRECO trial of divesiran, a first-in-class TMPRSS6-targeting siRNA product candidate developed from the company's proprietary mRNAi GOLD platform. The trial enrolled 48 phlebotomy-dependent adults with polycythemia vera (PV) and evaluated divesiran 6 mg/kg administered subcutaneously every 6 weeks (Q6W) or every 12 weeks (Q12W) versus placebo over a 36-week randomized double-blind period. Results: 88% of divesiran-treated patients achieved a response versus 19% on placebo (P<0.0001), corresponding to a 69% placebo-adjusted response rate. How divesiran works: it silences TMPRSS6 (transmembrane serine protease 6) expressed almost exclusively in the liver; TMPRSS6 is a negative regulator of hepcidin, the body's master regulator of iron metabolism. By silencing TMPRSS6, divesiran increases hepcidin production and release by liver hepatocytes, which restricts iron availability to bone marrow and reduces the excessive red blood cell production that drives PV symptoms. Divesiran has FDA Fast Track and Orphan Drug designations for PV. Silence Therapeutics anticipates initiating a Phase 3 trial evaluating divesiran Q12W versus placebo in the first half of 2027. Shares rose sharply on the news, touching a 52-week high. The read-through extends the broader siRNA cardiometabolic and rare-disease franchise landscape that also includes Alnylam's Amvuttra and Arrowhead's Redemplo (plozasiran) in adjacent hepatic-target siRNA categories.