Xenetic Biosciences and Santersus agree to all-stock combination targeting NETs

Xenetic Biosciences, Inc. and Santersus AG announced on September 16, 2026 that they had entered into a definitive share exchange agreement dated September 14, 2026, under which Xenetic will, subject to stockholder approval, acquire all of the outstanding share capital of Santersus in exchange for newly issued shares of Xenetic in an all-stock transaction.¹

Under the deal terms, existing Xenetic equity holders are expected to hold roughly 15.0% of the combined company and Santersus equity holders roughly 85.0%, on a fully diluted, as-converted basis, with adjustments possible depending on factors including Xenetic's net cash balance at closing.¹ A separate calculation in the filing states that immediately after closing, Santersus shareholders are expected to hold about 85% of outstanding common stock, with existing Xenetic stockholders holding the remainder, assuming net cash of $0 at closing.¹

Following the transaction, Santersus will become a wholly owned subsidiary of Xenetic, and Xenetic is expected to be renamed Santersus Bio, Inc., with headquarters remaining in Framingham, Massachusetts.¹ The company said James Ladtkow, current CEO of Santersus, is expected to lead the combined organization along with the rest of the existing Santersus management team.¹

The combined pipeline covers four programs: NucleoCapture for sepsis and for systemic lupus erythematosus, both holding FDA Breakthrough Device Designation, a liver transplantation program, and a DNase-CAR-T combination study in B-cell lymphoma. Closing is expected in the fourth quarter of 2026, subject to stockholder approval, Nasdaq listing approval, and effectiveness of a Form S-1 registration statement.¹ If the agreement is terminated under specified circumstances, Xenetic may owe Santersus a $500,000 termination fee, and each party could be required to reimburse the other for fees up to $300,000.¹