0001845337 2025-08-05 2025-08-05 0001845337 false 8-K 2025-08-05 DAY ONE BIOPHARMACEUTICALS, INC. DE 001-40431 83-2415215 1800 Sierra Point Parkway, Suite 200 Brisbane CA 94005 (650) 484-0899 false false false false Common Stock, par value $0.0001 per share DAWN NASDAQ false