City Therapeutics, a Phase 1 biotech developing RNA interference therapies for thromboembolic diseases, filed on Thursday with the SEC to raise up to $100 million in an initial public offering.
City Therapeutics is a clinical-stage biotech developing RNA interference (“RNAi”) therapeutics designed to silence the expression of disease-relevant proteins. It states that its current pipeline focused on indications with significant unmet medical need, including thromboembolic diseases, Stargardt disease type 1, and anemia of chronic disease, which it believes disease biology supports RNAi-mediated knockdown as a differentiated approach compared to other modalities. Its lead candidate, CITY-FXI, is a City-engineered GalNAc-conjugated small interfering RNA (“siRNA”) therapeutic candidate targeting Factor XI (“FXI”). City Therapeutics initiated a Phase 1 clinical trial for CITY-FXI in 2026, and states that initial data from the first three cohorts of the single-ascending dose (“SAD”) portion of the study in healthy volunteers showed that CITY-FXI was generally well-tolerated by participants with greater than 60% FXI knockdown observed following a single 15 mg subcutaneous dose, close to 80% FXI knockdown after a single 50 mg subcutaneous dose, and 85% knockdown three weeks after a single 150 mg subcutaneous dose. It expects to report additional data from the SAD portion of the Phase 1 study in late 2026.
The Cambridge, MA-based company was founded in 2023 and booked $14 million in revenue for the 12 months ended June 30, 2026. It plans to list on the Nasdaq under the symbol CTY. City Therapeutics filed confidentially on July 15, 2026. Goldman Sachs, Jefferies, Stifel, and Oppenheimer & Co. are the joint bookrunners on the deal. No pricing terms were disclosed.
