0001680581 2026-01-12 2026-01-12 false 0001680581 8-K 2026-01-12 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