On Oct. 19, 2026, Merck announced it it has entered into a definitive agreement to acquire Silence Therapeutics, a global clinical-stage biotechnology company headquartered in London, UK, focused on pioneering the design and development of siRNA (short interfering RNA) therapies in areas of high unmet need.

The purchase price of $20 per ADS in cash, with each ADS representing three ordinary shares of Silence Therapeutics (or $6.6667 per ordinary share), represents an enterprise value of $1.1 billion and an equity value of approximately $1.3 billion. The consideration represents an 82% premium to Silence Therapeutics’ 30-day volume-weighted average price of $10.99, as of the close of trading on October 16, 2026, the last trading day prior to the transaction announcement. The transaction is subject to satisfaction of customary closing conditions.

The transaction, once completed, will add Divesiran ─ a potentially best-in-class, phase 3-ready siRNA investigational therapy, in development for phlebotomy-dependent polycythemia vera (PV) ─ to Merck KGaA, Darmstadt, Germany’s pipeline. Divesiran is dosed subcutaneously once every 3 months.

PV is a chronic myeloproliferative neoplasm ─ a type of rare blood cancer ─ characterized by the excessive production of red blood cells, which can be associated with a higher rate of death from cardiovascular and thrombotic events.

Divesiran is designed to selectively silence TMPRSS6, a gene involved in regulating hepcidin, the body’s key regulator of iron metabolism. By increasing hepcidin levels, Divesiran aims to limit iron availability for red blood cell production, helping to control hematocrit levels and potentially reducing the need for frequent therapeutic phlebotomies.

Divesiran met its primary endpoint in the Phase 2 SANRECO study with an 88% responder rate versus 19% for placebo (p<0.0001) and reduced mean phlebotomies to 0.2 per patient versus 2.1 on placebo over weeks 0–36 (p<0.0001), irrespective of background cytoreductive therapy. Divesiran was observed to be well-tolerated and no new safety findings were observed in the trial. Injection site reactions were infrequent and self-limiting. There were two cases of Grade 1 anemia which were assessed as related to treatment by an investigator. 

The transaction has been unanimously approved by Silence Therapeutics’ Board of Directors and Merck KGaA, Darmstadt, Germany’s relevant corporate bodies and is expected to close in the first quarter of 2027, subject to satisfaction of customary closing conditions, including receipt of required regulatory approvals and approval by Silence Therapeutics’ shareholders.