Director David J. Portman filed a Form 4 with the SEC on October 28, 2026, disclosing that Sermonix Pharmaceuticals, Inc. partially exercised a warrant and assigned the remaining warrant rights, both on October 26, 2026, in connection with LeonaBio, Inc. (NASDAQ:LONA) common stock.

Key Highlights

  • Warrant partial exercise: Sermonix Pharmaceuticals, Inc. exercised a warrant on October 26, 2026, receiving 3,149,740 common shares of LeonaBio, Inc., according to the filing.
  • Remaining warrant assigned: The balance of the warrant was assigned to Perceptive Xentogeny Venture Fund II, LP as a distribution-in-kind pursuant to a plan of distribution to Sermonix Pharmaceuticals equity holders.
  • Price reported: The purchase transaction recorded a price of $3,149.47, as stated in the filing for both the common stock acquisition and the derivative security.
  • Indirect ownership: The 3,149,470 common shares listed in Table I are held indirectly, with Portman reporting voting control as Chief Executive Officer of Sermonix Pharmaceuticals, Inc.
  • Ownership threshold noted: The filing states that "Dr. Portman's personal indirect beneficial ownership does not exceed 10% of the stock in the Issuer."
  • Warrant terms: The warrant carried an exercise price of $0.001 and, according to the filing, does not expire.

Sermonix Warrant Exercise and Assignment in LeonaBio Detailed

According to the Form 4 filed October 28, 2026, David J. Portman, listed as a director of LeonaBio, Inc. (NASDAQ:LONA), reported transactions that took place on October 26, 2026, involving common stock and a warrant held by Sermonix Pharmaceuticals, Inc. Portman serves as Chief Executive Officer of Sermonix Pharmaceuticals and, per the filing, has voting control over the securities it holds. The filing notes, however, that his personal indirect beneficial ownership does not exceed 10% of LeonaBio stock.

In Table I, the filing reports an acquisition (transaction code "P") of 3,149,470 common shares at a price of $3,149.47, resulting in a following beneficial ownership of 3,149,470 shares held indirectly. In Table II, a warrant with an exercise price of $0.001 is reported. The filing explains in its responses that the warrant was exercised in part on October 26, 2026, producing 3,149,740 common shares for Sermonix Pharmaceuticals. The balance of the warrant was assigned to Perceptive Xentogeny Venture Fund II, LP as a distribution-in-kind pursuant to a plan of distribution to the Sermonix Pharmaceuticals equity holders. Following these events, Sermonix Pharmaceuticals holds 3,149,740 common shares of LeonaBio, Inc., as stated in the filing. The warrant carries no expiration date, according to the filing's explanation of responses.

The filing is signed by David J. Portman and dated October 28, 2026. It was filed individually, with the reporting person identified at 250 E. Broad St., Suite 250, Columbus, Ohio 43215.

What Was Disclosed

David J. Portman filed a Form 4 disclosing Sermonix Pharmaceuticals' partial exercise of a no-expiry warrant into 3,149,740 LeonaBio common shares on October 26, 2026, and the assignment of the remaining warrant to Perceptive Xentogeny Venture Fund II, LP as a distribution-in-kind.