Nektar Therapeutics

Item 1.01 Entry into a Material Definitive Agreement. On April 21, 2026, Nektar Therapeutics (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with Jefferies LLC, TD Securities (USA) LLC, and Piper Sandler & Co. (collectively, the “Representatives”) as the representatives of the several underwriters named therein (the “Underwriters”), relating to an underwritten offering (the “Offering”) of 3,532,609 shares (the “Firm Shares”) of the Company’s common stock, $0.0001 par value per share (the “Common Stock”) at a price to the public of $92.00 per Firm Share, less underwriting discounts and commissions. The Company also granted the Underwriters a 30-day option to purchase up to an additional 529,891 shares of Common Stock (the “Option Shares”, and together with the Firm Shares, the “Shares”) at the public offering price, less underwriting discounts and commissions, which the Underwriters exercised in full on April 22, 2026. All of the Shares in the Offering are being sold by the Company. The offering is expected to close on April 23, 2026, subject to customary closing conditions. The Company estimates that the net proceeds from the Offering will be approximately $350.9 million, after deducting underwriting discounts and commissions and estimated offering expenses payable by the Company. The Shares were issued pursuant to a shelf registration statement on Form S-3ASR (File No. 333-291466), as filed with the U.S. Securities and Exchange Commission (“SEC”) on November 12, 2025, which automatically became effective on November 12, 2025. A prospectus supplement relating to the Offering has been filed with the SEC dated April 21, 2026. The Underwriting Agreement contains customary representations, warranties, covenants, indemnification obligations of the Company and the Underwriters, including for liabilities under the Securities Act of 1933, as amended, and other obligations of the parties. The representations, warranties and covenants contained in the Underwriting Agreement were made only for purposes of such agreement and as of specific dates, were solely for the benefit of the parties to such agreement, and may be subject to limitations agreed upon by the contracting parties. The foregoing is only a brief description of the terms of the Underwriting Agreement, does not purport to be a complete statement of the rights and obligations of the parties under the Underwriting Agreement, and the transactions contemplated thereby, and is qualified in its entirety by reference to the Underwriting Agreement, which is filed as Exhibit 1.1 to this Current Report on Form 8-K and is incorporated herein by reference. A copy of the legal opinion of Goodwin Procter LLP relating to the issuance and sale of the Shares is filed as Exhibit 5.1 to this Current Report on Form 8-K and is filed with reference to, and is hereby incorporated by reference into, the Registration Statement.

Item 8.01 Other Events. The full text of the press release announcing the pricing of the underwritten offering on April 21, 2026 is attached as Exhibit 99.1 hereto and is incorporated herein by reference.