siRNA upstart ADARx (ADRX.US) launches a $350 million IPO, with AbbVie subscribing to a 4.9% stake and contributing up to $100 million.

ADARx Pharmaceuticals, a Phase 3 clinical-stage biotech company developing siRNA therapies for the treatment of multiple diseases, announced the terms of its IPO on Monday. The company plans to raise $350 million by offering 21.9 million shares at a price range of $15 to $17. AbbVie has agreed to subscribe for a certain number of shares in a concurrent private placement, which will give it a 4.9% stake upon completion of the transaction; based on the midpoint of the price range, this implies an investment of approximately $80 million, and its total investment will not exceed $100 million. Based on the midpoint of the proposed price range, ADARx Pharmaceuticals would achieve a fully diluted market value of $1.8 billion. ADARx Pharmaceuticals focuses on developing next-generation small interfering RNA (siRNA) therapies aimed at treating a broad range of diseases. The company's pipeline includes three clinical-stage programs and two late-stage preclinical programs. All three of its clinical-stage candidates target liver tissue and are currently being evaluated for the treatment of complement-mediated diseases, hereditary angioedema, and thrombotic disorders. The other two programs are at or advancing toward IND (Investigational New Drug application)-enabling stages, targeting obesity and neurodegenerative diseases, including Alzheimer's disease, respectively. ADARx Pharmaceuticals was founded in 2019 and generated $6 million in revenue during the 12 months ended June 30, 2026. The company plans to list on the Nasdaq under the ticker ADRX. JPMorgan, Morgan Stanley, TD Cowen, UBS Investment Bank, and LifeSci Capital are serving as joint book-running managers for the transaction. Pricing is expected in the week of Monday, September 21, 2026.