12. Subsequent Event

On July 26, 2026, the Company entered into an Agreement and Plan of Merger (the “Merger Agreement”) with argenx BV, a private company with limited liability organized under Belgian law (“argenx”), and Avena Merger Sub Inc., a Delaware corporation and wholly-owned subsidiary of argenx (“Purchaser”). The Merger Agreement provides for the acquisition of the Company by argenx through a tender offer for all outstanding shares of the Company’s common stock at $77.00 per share in cash, without interest and subject to any required withholding tax, followed by a merger of Purchaser with and into the Company, with the Company surviving as a wholly-owned subsidiary of argenx. The Company’s board of directors has unanimously recommended that stockholders tender their shares in the offer. Consummation of the transaction is subject to customary closing conditions, including a minimum tender condition and expiration of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, and is not subject to a financing condition. The Merger Agreement contains customary termination rights, including an obligation of the Company to pay argenx a termination fee of $65 million under specified circumstances. See “Pending Acquisition by argenx” in Part I, Item 2 of this Form 10-Q for additional information.