Oruka Therapeutics Announces Proposed $500 Million Underwritten Public Offering

MENLO PARK, Calif., April 27, 2026 — Oruka Therapeutics, Inc. (Nasdaq: ORKA), a clinical-stage biopharmaceutical company focused on developing novel monoclonal antibody therapeutics for psoriasis and other inflammatory and immunology indications, today announced that it has commenced an underwritten public offering of $500 million of shares of its common stock and, in lieu of common stock to certain investors, pre-funded warrants to purchase shares of its common stock. In addition, Oruka expects to grant the underwriters a 30-day option to purchase up to an additional $75 million of shares of its common stock at the public offering price, less underwriting discounts and commissions. The proposed public offering is subject to market and other conditions, and there can be no assurance as to whether or when the offering may be completed or as to the actual size or terms of the offering. All of the shares of common stock and pre-funded warrants are being offered by Oruka.

Leerink Partners, TD Cowen, Goldman Sachs & Co. LLC, Stifel and Guggenheim Securities are acting as joint bookrunning managers for the proposed offering. LifeSci Capital is acting as passive bookrunning manager for the proposed offering.

A shelf registration statement on Form S-3 (File No. 333-294852) relating to these securities has been filed with the Securities and Exchange Commission (the “SEC”) and became effective on April 10, 2026. This offering is being made solely by means of a prospectus supplement and accompanying prospectus. A preliminary prospectus supplement and accompanying prospectus relating to and describing the terms of the offering will be filed with the SEC and will be available on the SEC's website located at http://www.sec.gov. A copy of the preliminary prospectus supplement and the accompanying prospectus relating to the offering may be obtained, when available, from: Leerink Partners LLC, Syndicate Department, 53 State Street, 40th Floor, Boston, MA 02109, or by telephone at (800) 808-7525 ext. 6105, or by email at [email protected]; TD Securities (USA) LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, or by email at [email protected]; Goldman Sachs & Co. LLC, Attention: Prospectus Department, 200 West Street, New York, NY 10282, by telephone at (866) 471-2526 or by email at [email protected]; Stifel, Nicolaus & Company, Incorporated, Attention: Prospectus Department, One Montgomery Street, Suite 3700, San Francisco, CA 94104, by telephone at +1(415) 364-2720 or by email at [email protected]; or Guggenheim Securities, LLC, Attention: Equity Syndicate Department, 330 Madison Avenue, 8th Floor, New York, NY 10017, by telephone at (212) 518-9544, or by email at [email protected].

This press release shall not constitute an offer to sell, or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Oruka

Oruka Therapeutics is developing novel biologics designed to set a new standard for the treatment of chronic skin diseases. Oruka’s mission is to offer patients suffering from chronic skin diseases like plaque psoriasis the greatest possible freedom from their condition by achieving high rates of complete disease clearance with dosing as infrequently as once or twice per year. Oruka is advancing a proprietary portfolio of potentially best-in-class antibodies that were engineered by Paragon Therapeutics and target the core mechanisms underlying plaque psoriasis and other dermatologic and inflammatory diseases.

Investor Contact

Alan Lada (650) 606-7911 [email protected]