Adicet Bio, Inc.

Item 7.01. Regulation FD Disclosure. On January 7, 2026, Adicet Bio, Inc. (Adicet or the Company) issued a press release titled “Adicet Bio Provides Corporate Update and Highlights Expected 2026 Milestones,” a copy of which is furnished herewith as Exhibit 99.1 to this Current Report on Form 8-K. The information in this Item 7.01, including Exhibit 99.1 attached hereto, is intended to be furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the Exchange Act), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 8.01. Other Events. On January 7, 2026, the Company announced that enrollment in its prulacabtagene leucel (prula-cel, formerly ADI-001) Phase 1 program in autoimmune diseases has doubled to over 20 patients as of December 31, 2025. The Company also reached alignment with the U.S. Food and Drug Administration (FDA) to allow patients with lupus nephritis and systemic lupus erythematosus to be dosed with prula-cel in the outpatient setting in ongoing and future clinical trials. The Company plans to request a meeting with the FDA in the second quarter of 2026 to inform potential Phase 2 pivotal trial design for prula-cel. On January 7, 2026, the Company also announced that it plans to submit a regulatory filing for ADI-212 in metastatic castration-resistant prostate cancer in the first half of 2026. Forward-Looking Statements The disclosure under this Item 8.01 contains "forward-looking statements" of Adicet within the meaning of the Private Securities Litigation Reform Act of 1995 relating to the business and operations of Adicet. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, but are not limited to, express or implied statements regarding Adicet’s expectations regarding the clinical development of prula-cel, including the dosing in the outpatient setting in ongoing and future clinical trials and plans for a meeting with the FDA, and expectations for the timing of a regulatory filing for ADI-212 in metastatic castration-resistant prostate cancer. Any forward-looking statements in this Item 8.01 are based on management's current expectations and beliefs of future events, and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in or implied by such forward-looking statements, including without limitation, the effect of global economic conditions and public health crises on the Company’s business and financial results, including with respect to disruptions to its preclinical and clinical studies, business operations, employee hiring and retention, and ability to raise additional capital; Adicet's ability to execute on its strategy including obtaining the requisite regulatory approvals on the expected timeline, if at all; that positive results, including interim results, from a preclinical or clinical study may not necessarily be predictive of the results of future or ongoing studies; that clinical studies may fail to demonstrate adequate safety and efficacy of Adicet’s product candidates, which would prevent, delay, or limit the scope of regulatory approval and commercialization; and regulatory approval processes of the FDA and comparable foreign regulatory authorities are lengthy, time-consuming, and inherently unpredictable; and Adicet’s ability to meet production and product release expectations. For a discussion of these and other risks and uncertainties, and other important factors, any of which could cause Adicet's actual results to differ from those contained in the forward-looking statements, see the section titled "Risk Factors" in Adicet's most recent Quarterly Report on Form 10-Q and subsequent filings with the U.S. Securities and Exchange Commission (SEC), as well as discussions of potential risks, uncertainties, and other important factors in Adicet’s other filings with the SEC. All disclosure under this Item 8.01 is as of the date of this Form 8-K, and Adicet undertakes no duty to update this information unless required by law.