X0202 SCHEDULE 13G/A 0000938206 XXXXXXXX LIVE 1 Common Stock 06/30/2026 0001813814 Definium Therapeutics, Inc. 24477V105 One World Trade Center, Suite 8500 New York NY 10007 Rule 13d-1(b) DRIEHAUS CAPITAL MANAGEMENT LLC DE 0 6845276 0 6845276 6845276 N 5.36 IA The issuer changed its name from Mind Medicine (MindMed), Inc. to Definium Therapeutics, Inc. on January 12, 2026. This amendment is filed to reflect the change in our percentage of ownership of Definium Therapeutics, Inc. (DFTX). DCM owned 5.36% of DFTX as of June 30, 2026, down from 6.64% as of December 31, 2025. Definium Therapeutics, Inc. One World Trade Center, Suite 8500, New York, New York, 10007 Driehaus Capital Management LLC 25 East Erie Street, Chicago, Illinois 60611 USA N IA 6845276 5.36 0 6845276 0 6845276 Y N The shares reported by Driehaus Capital Management LLC (DCM) are held by numerous clients on a fully discretionary basis in accounts managed by DCM. Securities held in these clients' accounts are included in this report to reflect that DCM may have voting power and has dispositive power. To the best of DCM's knowledge, none of the referenced clients have the right to receive dividends or direct proceeds from the sale of interests relating to more than 5% of the class. Y Y Y N By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11. DRIEHAUS CAPITAL MANAGEMENT LLC Janet McWilliams 08/14/2026