IDEAYA Announces Closing of Public Offering Including Full Exercise of Underwriters' Option to Purchase Additional Shares

SOUTH SAN FRANCISCO, Calif.,June 10, 2026/PRNewswire/ -- IDEAYA Biosciences, Inc. (Nasdaq:IDYA) today announced the closing of its underwritten public offering of 7,222,225 shares of its common stock at a public offering price of $27.00 per share, before underwriting discounts and commissions, and pre-funded warrants to purchase 5,555,576 shares of common stock at a public offering price of $26.9999 per pre-funded warrant, before underwriting discounts and commissions. This includes the exercise in full by the underwriters of their option to purchase up to an additional 1,666,669 shares of common stock in the offering. The gross proceeds from the offering, before deducting underwriting discounts and commissions and other offering expenses payable by IDEAYA, were approximately $345.0 million.

J.P. Morgan, Jefferies, TD Cowen, UBS Investment Bank, and Cantor acted as joint book-running managers for the offering. Wedbush PacGrow acted as lead manager for the offering.

The public offering was made by IDEAYA pursuant to an automatically effective shelf registration statement on Form S-3 that was previously filed with the U.S. Securities and Exchange Commission, or the SEC. The offering was made only by means of a written prospectus and prospectus supplement that form a part of the registration statement. A final prospectus supplement and accompanying prospectus relating to the offering has been filed with the SEC and is available on the SEC's website athttp://www.sec.gov. Copies of the final prospectus supplement and the accompanying prospectus relating to the offering may also be obtained by request from: J.P. Morgan, by mail at J.P. Morgan Securities LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, or by email at[email protected]and[email protected]; Jefferies, by mail at Jefferies LLC, Attention: Equity Syndicate Prospectus Department, 520 Madison Avenue, New York, NY 10022, or by telephone at 877-547-6340 or 877-821-7388, or by email at[email protected]; TD Securities, by mail at TD Securities (USA) LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, or by email at[email protected]; UBS Investment Bank, by mail at UBS Securities LLC, 11 Madison Avenue, New York, NY 10010, Attention: Equity Syndicate, or by email at[email protected]; or Cantor, by mail at Cantor Fitzgerald & Co., Attention: Capital Markets, 110 East 59th Street, 6th Floor, New York, NY 10022, or by email at[email protected].

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

IDEAYA is a precision medicine oncology company committed to the discovery, development, and commercialization of transformative therapies for cancer. Our approach integrates expertise in small-molecule drug discovery, structural biology and bioinformatics with robust internal capabilities in identifying and validating translational biomarkers to develop tailored, potentially first-in-class targeted therapies aligned to the genetic drivers of disease. We have built a deep pipeline of product candidates focused on synthetic lethality and antibody-drug conjugates, or ADCs, for molecularly defined solid tumor indications. Our mission is to bring forth the next wave of precision oncology therapies that are more selective, more effective, and deeply personalized with the goal of altering the course of disease and improving clinical outcomes for patients with cancer.

SOURCE IDEAYA Biosciences, Inc.