Black Hawk Acquisition Corp and Vesicor Therapeutics Enter Forward Purchase Agreement with Meteora for Up to 1.35M Shares; Company To Domesticate As A Delaware Corporation And Change Name To Vesicor Therapeutics Holdings; Co To Pay Meteora Final Redemption Price Less $0.75 Per Backstop Investor Share; Vesicor Therapeutics Holdings May Sell Up To $200M Of Common Stock To Meteora Over 36 Months

On September 22, 2026, Black Hawk Acquisition Corporation, a Cayman Islands exempted company ("BKHA" or the "Company"), and Vesicor Therapeutics, Inc., a California corporation ("Vesicor"), entered into a series of financing and related agreements with Meteora Select Trading Opportunities Master, LP ("Meteora") in connection with the Company’s previously announced business combination with Vesicor (the "Business Combination"). Pursuant to the Business Combination Agreement, dated April 26, 2025, by and among the Company, BH Merger Sub, Inc. and Vesicor (as amended or otherwise modified from time to time, the "Business Combination Agreement"), the Company will domesticate as a Delaware corporation and change its name to "Vesicor Therapeutics Holdings, Inc." ("PubCo"), and Vesicor will become a wholly owned subsidiary of PubCo.

Forward Purchase Agreement

On September 22, 2026, the Company, Vesicor and Meteora entered into an OTC Equity Prepaid Forward Transaction confirmation (the "Forward Purchase Agreement"). The Forward Purchase Agreement provides for a share forward transaction with respect to up to 1,350,000 shares (the "Maximum Number of Shares"), subject to an upward adjustment upon the occurrence of certain dilutive offerings. The shares subject to the transaction may consist of (i) shares purchased by Meteora from third parties in the open market for which Meteora irrevocably waives redemption rights ("Recycled Shares") and (ii) shares purchased directly from the Company pursuant to the Subscription Agreement described below ("Additional Shares"). The aggregate number of Recycled Shares and Additional Shares may not exceed the Maximum Number of Shares.

The initial price under the Forward Purchase Agreement will equal the per-share redemption price payable to holders of the Company’s public ordinary shares in connection with the Business Combination (the "Initial Price"). Subject to receipt of the applicable pricing date notice, at or in connection with the closing of the Business Combination the Company will pay Meteora, from the trust account, a prepayment amount equal to the number of shares specified in the pricing date notice multiplied by the Initial Price, reduced dollar-for-dollar by the aggregate purchase price funded by Meteora for any Additional Shares under the Subscription Agreement. The reset price will initially be $10.00 per share and may be reduced by mutual written agreement or upon certain dilutive offerings.