Sermonix Pharmaceuticals Reports 36.9% Stake in LeonaBio via Warrant Exercise

Sermonix Pharmaceuticals, Inc., along with its CEO David Portman, filed a Schedule 13D reporting a 36.9% ownership stake in LeonaBio, Inc. (formerly Athira Pharma, Inc.). This position consists of 5,502,402 shares of Common Stock underlying prefunded warrants that became exercisable on August 24, 2026. These warrants were originally acquired as consideration for a strategic collaboration and intellectual property licensing agreement involving the drug lasofoxifene. The filing details several planned transactions effective October 26, 2026: Sermonix intends to exercise warrants for 3,149,470 shares and execute a distribution-in-kind of 4,725,754 shares to its shareholders, including Perceptive Xontogeny Venture Fund II, LP. Additionally, 170,940 shares will be assigned to a creditor to satisfy outstanding debts. David Portman also holds options for 350,000 shares granted for consulting services, which begin vesting in April 2027. This filing marks a significant strategic entry by Sermonix into LeonaBio's equity structure following the removal of a previous 4.99% exercise cap.