Atlas Venture Opportunity Fund II, L.P. Sells Sionna Therapeutics, Inc. Common Stock

Atlas Venture Opportunity Fund II, L.P. has filed a notice of sale of Sionna Therapeutics, Inc. common stock. The filing details the sale of 29,363 shares acquired through a private placement on March 4, 2024. The notice, signed by Ommer Chohan on October 16, 2025, indicates that the securities were sold on the same date. The aggregate market value of the securities sold is $907,610.33. Additionally, the filing includes details of recent transactions over the past three months, totaling significant amounts of securities sold. The transactions were facilitated through Merrill Lynch, with the securities listed on NASDAQ.