Summit Therapeutics Inc. (NASDAQ: SMMT) announced it has commenced an underwritten public offering of $500 million in common stock shares. The biopharmaceutical company is offering all shares in the proposed offering.

Summit plans to grant underwriters a 30-day option to purchase up to an additional $75 million of shares at the public offering price, minus underwriting discounts and commissions. The company stated the offering is subject to market and other conditions, with no assurance regarding completion timing or final terms.

The company intends to use net proceeds from the offering, combined with existing cash and cash equivalents, to fund research and development of its lead product candidate ivonescimab. Additional funds will support working capital and general corporate purposes.

J.P. Morgan, Goldman Sachs & Co. LLC and Citigroup are serving as joint book-running managers for the proposed offering.

Summit is conducting the offering under a shelf registration statement on Form S-3 that became effective on June 9, 2026. A preliminary prospectus supplement and accompanying base prospectus will be filed with the Securities and Exchange Commission.

The Miami-based biopharmaceutical oncology company focuses on discovering, developing and commercializing cancer therapies. Summit was founded in 2003 and maintains additional offices in Palo Alto, Princeton, Dublin and Oxford.