0001680581 2025-12-10 2025-12-10 0001680581 false 8-K 2025-12-10 Fulcrum Therapeutics, Inc. DE 001-38978 47-4839948 26 Landsdowne Street Cambridge MA 02139 (617) 651-8851 N/A false false false false Common stock, par value $0.001 per share FULC NASDAQ false