X0609 4 2026-04-20 0002091349 First Tracks Biotherapeutics, Inc. TRAX 0001370053 ANAPTYSBIO, INC false 10770 WATERIDGE CIRCLE, SUITE 210 SAN DIEGO CA 9212 false false true false 0 Common Stock, par value $0.001 per share 2026-04-20 4 J 0 100 D 0 D On April 1, 2026, AnaptysBio, Inc., a Delaware corporation ("AnaptysBio"), reported that it owned 100 shares of common stock, par value $0.001 per share, of First Tracks Biotherapeutics, Inc. ("First Tracks"), which at the time constituted all of the issued and outstanding shares of common stock of First Tracks. The record date for the distribution by AnaptysBio of all shares of common stock of First Tracks to the holders of AnaptysBio common stock was April 20, 2026 (the "Spin-Off"). The Spin-Off occurred before the market opened on April 20, 2026. Represents the outstanding shares of common stock of First Tracks as of April 20, 2026, which were distributed in the Spin-Off as defined in footnote 2 on April 20, 2026. /s/ Dan Faga, Chief Executive Officer and President of AnaptysBio, Inc. 2026-04-22