Adicet Bio : Investor Presentation

Allogeneic Gamma Delta T Cells Engineered to Fight Cancer

Forward-Looking Statements

This presentation does not constitute an offer or invitation for the sale or purchase of securities and has been prepared solely for informational purposes. This presentation may contain "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, statements regarding: future product development plans and projected timelines for the initiation and completion of preclinical and clinical trials and other activities of Adicet Bio, Inc. (the "Company" or "Adicet"); the potential for the results of ongoing preclinical or clinical trials and the efficacy of Adicet's drug candidates; our expectations of the potential impact of COVID-19 on strategy, future operations, and the timing of our clinical trials, including potential impacts on enrollment and initiation; and future product development and regulatory strategies, including with respect to specific indications. The use of words such as, but not limited to, "believe," "expect," "estimate," "project," "intend," "future," "potential," "continue," "may," "might," "plan," "will," "should," "seek," "anticipate," or "could" and other similar words or expressions are intended to identify forward-looking statements. Forward- looking statements are neither historical facts nor assurances of future performance. Instead, they are based on Adicet's current beliefs, expectations and assumptions regarding the future of Adicet's business, future plans and strategies, clinical results and other future conditions. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.

Such forward-looking statements are subject to a number of material risks and uncertainties that are discussed in the section entitled "Risk Factors" in resTORbio, Inc. ("resTORbio")'s annual report on Form 10-K for the fiscal year ended December 31, 2019; in its filings on Form 10-Q, dated May 7, 2020, July 31, 2020 and November 5, 2020, respectively; in Adicet's filing on Form 8-K dated September 15, 2020, and also including, but not limited to: (i) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (ii) unanticipated difficulties or expenditures relating to the merger, the response of business partners and competitors to the announcement or completion of the merger, and/or potential difficulties in employee retention as a result of the announcement or completion of the merger; (iii) the combined company's listing on the Nasdaq Global Select Market; (iv) the adequacy of the combined company's capital to support its future operations, and its ability to successfully initiate and complete clinical trials; (v) the nature, strategy and focus of the combined company; (vi) the difficulty in predicting the time and cost of development of Adicet's product candidates; (vii) Adicet's plans to develop and commercialize its product candidates, including, but not limited to, ADI-001 and ADI-002; (viii) the timing of initiation of Adicet's planned clinical trials;

1. the timing of the availability of data from Adicet's clinical trials; (x) the timing of any planned investigational new drug application or new drug application; (xi) Adicet's plans to research, develop and commercialize its current and future product candidates; (xii) Adicet's ability to enter into new collaborations, and to fulfill its obligations under any such collaboration agreements; (xiii) the clinical utility, potential benefits and market acceptance of Adicet's product candidates; (xiv) Adicet's commercialization, marketing and manufacturing capabilities and strategy; (xv) Adicet's ability to identify additional products or product candidates with significant commercial potential and to expand its pipeline in oncology and other diseases; (xvi) developments and projections relating to Adicet's competitors and its industry; (xvii) the impact of government laws and regulations; (xviii) the impact of public health epidemics affecting countries or regions in which we have operations or do business, such as COVID-19, which has been labeled a pandemic by the World Health Organization, the timing and anticipated results of our clinical trials; (xix) the risk that the results of our clinical trials may not be predictive of future results in connection with future clinical trials; (xx) the timing and outcome of our planned interactions with regulatory authorities; (xxi) Adicet's ability to protect its intellectual property position; (xxii) Adicet's estimates regarding future revenue, expenses, capital requirements and need for additional financing; and (xxiii) those risks detailed in resTORbio's, Inc.'s definitive proxy statement/prospectus/information statement filed with the SEC on August 21, 2020, as well as discussions of potential risks, uncertainties, and other important factors in Adicet's subsequent filings with the Securities and Exchange Commission. Any forward-looking statement speaks only as of the date on which it was made. None of Adicet, nor its affiliates, advisors or representatives, undertake any obligation to publicly update or revise any forward-looking statement, whether as result of new information, future events or otherwise, except as required by law.

Industry and Market Information

Information regarding market share, market position and industry data pertaining to Adicet's business contained in this presentation consists of estimates based on data and reports compiled by industry professional organizations and analysts and Adicet's knowledge of their industry. Although Adicet believes the industry and market data to be reliable, this information could prove to be inaccurate. You should carefully consider the inherent risks and uncertainties associated with the market and other industry data contained in this presentation. Forward-looking information obtained from third-party sources is subject to the same qualifications and the additional uncertainties as the other forward-looking statements in this presentation.

Adicet Bio: Leaders in Engineered Gamma-DeltaCAR-T Cell Therapy

• Developing off-the-shelf, engineered Gamma-Delta (γδ) CAR-T cell candidates for oncology and other indications
• Presence of γδ T cells in tumors observed to strongly correlate with improved overall prognosis, survival and PFS
• The following factors support the potential for γδ T cells to be successfully developed into therapies:
• • Express T-cell and NK cell receptors, facilitating adaptive and innate anti-tumor immune responses with more limited ability for tumor escape
  • Intrinsically home to and function in tissues and solid malignancies
  • Potential to be developed for allogeneic and off-the-shelf approaches; potential to re-dose patients
  • Potential for outpatient administration
• Proprietary T Cell Receptor-Like(TCR-L) monoclonal platform targeting intracellular targets presented on MHC complexes
• $108 million cash and cash equivalents and marketable debt securities as of Sept. 30, 2020
• Multiple near-term milestones
• Key Investors: OrbiMed, Novartis, JNJ, Regeneron, aMoon

CAR: Chimeric Antigen Receptors; NK: Natural Killer; GvHD: Graft Versus Host Disease; MHC: Major Histocompatibility

3 Complex; NKG2D: NK Group 2D; NCR=Natural Cytotoxicity Receptors; DNAM-1: DNAX accessory molecule-1

Adicet Bio Post-Merger Leadership Team

Chen Schor

President and CEO

Francesco Galimi, MD, PhD

Chief Medical Officer

Carrie Krehlik

Chief Human Resource Officer

Don Healey, Ph.D.

Chief Technology Officer

Stewart Abbot, PhD

Chief Scientific and Operating Officer

Lloyd Klickstein, MD, PhD

Chief Innovation Officer

Nick Harvey

Chief Financial Officer

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