Merck KGaA has agreed to acquire Silence Therapeutics, a Cambridge, UK-based clinical-stage bio/pharmaceutical company developing short interfering RNA (siRNA) medicines, for $1.3 billion, representing an enterprise value of $1.1 billion.  

Silence Therapeutics applies its proprietary mRNAi GOLD platform to develop siRNA therapies designed to target and silence genes that cause disease The company’s lead asset is divesiran, in Phase II development for treating phlebotomy-dependent polycythemia vera (PV), a rare blood cancer resulting in overproduction of red blood cells. Divesiran is designed to selectively silence TMPRSS6, a gene involved in regulating hepcidin, a key regulator of iron metabolism. By increasing hepcidin levels, divesiran aims to limit iron availability for red blood cell production. The medicine has received both Fast Track and Orphan Drug designation for PV by the US Food and Drug Administration. The company’s second pipeline asset is zerlasiran, a siRNA medicine in Phase I/II development for treating high lipoprotein (a) (Lp[a]), a genetically determined cardiovascular risk factor. By silencing the LPA gene, levels of Lp(a) are lowered, which in turn is expected to lower the risk of heart diseases, such as heart attacks and strokes, according to information from Silence Therapeutics.  

The transaction has been unanimously approved by Silence Therapeutics’ Board of Directors and Merck KGaA’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.   

Certain shareholders of Silence, holding approximately 14% of Silence’s voting power, have entered into a voting and support agreement with Merck KGaA, to which the shareholders holders have agreed, among other things, to vote their beneficially owned voting securities of Silence in favor of the transaction. 

Source: Merck KGaA and Silence Therapeutics