Amendment to Schedule 13D Filing for VOR BIOPHARMA INC.

This filing is an amendment to a Schedule 13D originally filed on February 19, 2021, by RA Capital Management, L.P. and related entities (collectively, "Reporting Persons"). The amendment, dated March 16, 2026, supplements previous filings. The Reporting Persons hold an aggregate of 9,023,068 shares of VOR BIOPHARMA INC. common stock, representing 19.9% ownership. This ownership includes shares held directly by RA Capital Healthcare Fund, L.P., as well as shares underlying exercisable warrants and stock options. A key update involves a March 12, 2026 notice to increase the Maximum Percentage under the Pre-Funded Warrants from 9.99% to 19.99%, effective March 13, 2026. This increase results in the Reporting Persons being deemed beneficial owners of an additional 3,611,297 shares. The Reporting Persons have the power to vote and dispose of these shares, with RA Capital Management, L.P. acting as the investment adviser and holding sole voting and dispositional power for the Fund. None of the Reporting Persons have been convicted in criminal proceedings or been party to civil proceedings that would require disclosure.