Material Event (Form 8-K)

Item 8.01 Other Events.

On May 26, 2026, Editas Medicine, Inc. (the "Company") notified TD Securities (USA) LLC ("TD Cowen") that it was suspending and terminating the prospectus supplement, dated March 21, 2025, related to the sales agreement that the Company entered into with TD Cowen on May 14, 2021, as amended on February 28, 2024 and on March 5, 2025 (as amended, the "Sales Agreement"), and pursuant to which the Company may offer and sell shares of its common stock, $0.0001 par value per share (the "Common Stock"), from time to time through TD Cowen, as agent, under an "at-the-market" offering program. The Company will not make any sales of its Common Stock pursuant to the Sales Agreement unless and until a new prospectus or prospectus supplement is filed and, if applicable, a new registration covering such shares of Common Stock is declared effective by the Securities and Exchange Commission. The Sales Agreement remains in full force and effect. As of May 26, 2026, the Company had issued and sold an aggregate of 14,327,365 shares of its Common Stock under its "at-the-market" offering program with TD Cowen for aggregate gross sale proceeds of $43.9 million, before deducting sales commissions and offering expenses.

A copy of the Sales Agreement was filed as Exhibit 1.2 to the Company's Post-Effective Amendment No.1 to the Registration Statement on Form S-3 (333- 277471), filed with the Securities and Exchange Commission on March 5, 2025.