Announcement • Jun 13

Silence Therapeutics Presents Follow-Up And Quality-Of-Life Data From Phase 1 SANRECO Study Evaluating Divesiran In Polycythemia Vera Patients

Silence Therapeutics plc presented follow-up and quality-of-life data from the Phase 1 SANRECO study evaluating divesiran, a first-in-class siRNA therapy targeting TMPRSS6, in 21 phlebotomy-dependent patients with polycythemia vera (PV) at the European Hematology Association 2026 Annual Congress. Divesiran data presented at EHA show improvements in PV-related symptoms and quality-of-life, complementing the substantial reductions in phlebotomy use as previously reported. Additional analyses also showed substantial reductions in phlebotomy use persisted well beyond the final dose. In the six months prior to treatment, the 21 enrolled patients required a total of 80 phlebotomies. During the active treatment period, only 5 phlebotomies were required, all occurring in patients classified as “uncontrolled” at baseline with HCT levels greater than 45%. During the 16-week follow-up period after the final dose, only 4 phlebotomies were reported, supporting the prolonged duration of divesiran’s effect. Among 14 patients with further follow-up data, the median time to first phlebotomy was 287 days. The majority of patients experienced improvements in MPN-10 total symptom scores from baseline through Week 34, indicating potential improvements in disease-related symptoms and overall quality of life. Divesiran was well tolerated, with no dose-limiting toxicities observed. The most common treatment-emergent adverse events (TEAEs) were mild and transient injection-site reactions. No treatment-related serious adverse events or TEAEs leading to discontinuation were reported. The ongoing Phase 2 SANRECO study (NCT05499013) is evaluating divesiran using Q6W and Q12W dosing regimens in patients with PV. Topline data are expected in August 2026. The Phase 1 portion of SANRECO was a 34-week, open-label study evaluating divesiran (3 mg/kg, 6 mg/kg and 9 mg/kg) administered subcutaneously (s.c.) Q6W for four doses, with a 16-week follow-up period following the date of the last administered dose in 21 PV patients. Key inclusion criteria included a PV diagnosis and a history of requiring at least three phlebotomies in the last six months or five in the last year prior to screening. Patients were allowed to be on stable doses of cytoreductive agents. Given the exploratory nature of this Phase 1 study, both well-controlled patients - defined as those with HCT levels = 45% – as well as those with HCT levels > 45% at baseline on current standard-of-care treatment were enrolled. The Phase 2 portion of SANRECO is an ongoing, three-part, global, randomized, placebo-controlled, double-blind study evaluating divesiran in 48 phlebotomy-dependent PV patients. The trial is evaluating the safety and efficacy of divesiran 6 mg administered s.c. Q6W or Q12W in patients with uncontrolled HCT who are phlebotomy-dependent despite standard-of-care treatment which could include hydroxyurea, interferon and/or ruxolitinib. The primary endpoint of the study is the proportion of patients achieving a response during weeks 18-36, which is defined as the absence of “phlebotomy eligibility.” To meet phlebotomy eligibility, patients in the study are required to have HCT = 45%. Following the placebo-controlled portion of the trial, patients enter the 3-year, double-blind and open label extension periods. PV is a rare, myeloproliferative neoplasm – a type of blood cancer - characterized by the excessive production of red blood cells, often resulting in elevated hematocrit levels. Elevated hematocrit above 45% is associated with a four-times higher rate of death from cardiovascular and thrombotic events. PV is associated with a range of burdensome symptoms including fatigue, cognitive disturbance and pruritus and additionally, longer term can transform to myelofibrosis and Acute Myeloid Leukemia. The aim of treatment is to maintain hematocrit less than 45%, a level that is associated with a reduced incidence of thrombosis and CV-associated death. The current standard of care includes repeated phlebotomies to reduce hematocrit and/or cytoreductive agents to reduce red blood cell production. There are currently no approved therapies that specifically target red blood cells and hematocrit. Divesiran is Silence’s wholly owned siRNA product candidate developed from its proprietary mRNAi GOLD platform that “silences” TMPRSS6 expressed almost exclusively in the liver. TMPRSS6 is a negative regulator of hepcidin, the body's master regulator of iron metabolism including its absorption, distribution, and storage. By silencing TMPRSS6 in PV patients, divesiran aims to increase hepcidin production and release by liver hepatocytes, leading to the restriction of iron to the bone marrow and, thus, reducing the excessive production of red blood cells, a process dependent on availability of iron. Divesiran is currently in Phase 2 development for PV and has FDA Fast Track and Orphan Drug designations for PV.

Silence Therapeutics plc Stock Price

SLN Share Price Performance

SLN Community Narratives

ALPACAR-360 Success And AstraZeneca Collaboration Will Advance siRNA Pipeline

Advancements In RNAi Will Harness Aging Healthcare Demand

ALPACAR-360 Success And AstraZeneca Collaboration Will Advance siRNA Pipeline

Advancements In RNAi Will Harness Aging Healthcare Demand

Trending Discussion

Recently Updated Narratives

SLN: Upcoming Phase 2 Data And ATM Program Will Shape Upside Potential

Advancements In RNAi Will Harness Aging Healthcare Demand

Snowflake Analysis

Silence Therapeutics plc Key Details

About SLN

Recent SLN News & Updates

SLN: Upcoming Phase 2 Data And ATM Program Will Shape Upside Potential

Silence Therapeutics Presents Follow-Up And Quality-Of-Life Data From Phase 1 SANRECO Study Evaluating Divesiran In Polycythemia Vera Patients

Consensus EPS estimates upgraded to US$0.63 loss

Recent updates

Silence Therapeutics plc Competitors

Seaport Therapeutics

Sana Biotechnology

Xencor

Cullinan Therapeutics