Merck KGaA agreed to buy Silence Therapeutics for $1.3 billion, securing the siRNA therapy divesiran in development for polycythemia vera. The acquisition is positioned as an effort to build out Merck’s portfolio in rare and specialty diseases using genetic medicines, following prior RNA-focused steps. Silence’s divesiran is designed to target TMPRSS6. In a Phase 2 SANRECO study, divesiran achieved a responder rate of 87.5% versus 18.8% for placebo through week 36, supporting the rationale to advance toward pivotal testing. Analysts framed the transaction as reducing near-term execution risk in a competitive RNA space, while noting Merck will still need to fund and execute a Phase 3 program. Deal terms and timing were not fully detailed in the source, but Merck expects completion in early 2027.