<div id="readability-page-1"><div>Philadelphia, Pennsylvania and Oxford, United Kingdom--(Newsfile Corp. - November 17, 2025) - Adaptimmune Therapeutics plc (OTC Pink: ADAPY) (&#34;Adaptimmune&#34; or the &#34;Company&#34;) today announced changes to the Company's Board of Directors (&#34;Board&#34;) and its Executive Leadership team, which are effective from November 14, 2025.Christopher (Chris) Hill, currently Chief Financial Officer (&#34;CFO&#34;) of the Company, has been appointed as Chief Executive Officer (&#34;CEO&#34;) and a Director of the Company, succeeding Adrian Rawcliffe who has left in connection with the Company's restructuring. Mr. Hill is continuing to serve as CFO. William (Bill) Bertrand, formerly Chief Operating Officer, has also left the Company in connection with the restructuring.Lawrence Alleva, a current Board member, has been appointed as Chairman of the Company succeeding David Mott who has served as a director since 2014 and as Chairman since 2017. Garry Menzel will also continue to serve on the Board. In addition to Mr. Mott, the following Board members have resigned: Andrew Allen, Ali Behbahani, John Furey, Priti Hegde and Kristen Hege.Following the changes, the Board comprises Lawrence Alleva (Chairman), Garry Menzel and Chris Hill (also CEO and CFO).The changes follow on from the voluntary delisting of the Company's American Depositary Shares (&#34;ADSs&#34;) from Nasdaq on October 28, 2025. The Company's ADSs are quoted on the OTC Pink Limited Market under the symbol ADAPY.Chris Hill, Adaptimmune's new Chief Executive Officer: &#34;I am pleased to have been appointed to succeed Adrian who has served with Adaptimmune since 2015 as CFO and then CEO. I want to acknowledge the work of Adrian, Bill and my fellow Board members and thank them for their dedicated service over many years. The transaction with USWM CT, LLC, a subsidiary of US WorldMeds Partners, LLC (collectively, &#34;US WorldMeds&#34;) meant that TECELRA could continue to be made available to patients, and since closing on July 31, 2025, work has been ongoing to ensure a smooth transition of activities associated with TECELRA, lete-cel and uza-cel. We will continue to support US WorldMeds as we work together with a goal to achieve approval for lete-cel in the hope that it will benefit patients in the future. In parallel, we are maintaining a focus on efforts to maximize value from our remaining assets, including programs targeting PRAME and CD70. The delisting from Nasdaq and deregistration should reduce our costs as a public company and further support our goal to maximize value going forward.&#34;The Company has also initiated a process for deregistration of the ADSs under Section 12(b) of the Securities Exchange Act of 1934, as amended (the &#34;Exchange Act&#34;) which included the filing of a Form 25 with the Securities and Exchange Commission (&#34;SEC&#34;) on October 28, 2025 and of a Form 15 on November 13, 2025, upon which the Company's filing obligations under the Exchange Act were immediately suspended, including the obligations to file all periodic reports. The deregistration of the Company's ADSs under Section 12(b) of the Exchange Act is currently expected to become effective on or around January 26, 2026.Chris Hill has served as Adaptimmune's Chief Financial Officer since September 10, 2025 leading the Company's financial operations and strategy. He has over 10 years' experience of serving in chief financial officer and chief operating officer roles in public and private life science companies.From September 2021 through September 9, 2025, Mr. Hill served as Chief Financial Officer and Chief Operating Officer of Istesso Limited, a private drug development company with pre-clinical to phase IIb assets developing new therapies in auto-immune and fibrotic diseases. Previously, Mr. Hill served as part-time Chief Financial Officer of Ixaka Limited, a private cell therapy company, from April 2020 through September 2021 and as Finance Director of OxSonics Therapeutics Limited, a private clinical stage therapeutics company developing improved drug delivery solutions to solid tumour cancers, from March 2019 through September 2021.Mr. Hill served as Chief Financial Officer and a member of the Board of Directors of Oxford Pharmascience Group Plc, formerly a publicly listed drug development company on AIM focused on gastro-safe NSAIDs, from October 2013 through January 2018. Mr. Hill had responsibility for the financial, legal and HR functions within the group and for AIM and other regulatory reporting. During his tenure, the company underwent a demerger, and its operations were spun out into Abaco Capital (AIM: ABAA) and private company, Oxford Pharmascience Limited. His other prior roles include serving as Group Financial Controller at Ora Capital Partners Limited, previously an AIM-listed investment vehicle, from July 2010 through October 2013, and as Audit Senior at international audit, professional services and consulting firm, Grant Thornton UK LLP, from June 2005 to June 2010. He currently serves as a director of private companies, Connexin Therapeutics Group Limited and CJH Financial Limited.Mr. Hill is a chartered accountant and holds a B.A. degree in Economics and Public Policy from Leeds Metropolitan University.About AdaptimmuneWe are a biopharmaceutical company working to redefine the treatment of solid tumor cancers with cell therapies. In August 2024, the U.S. Food and Drug Administration (&#34;FDA&#34;) approved our first biologics license application (&#34;BLA&#34;) for TECELRA® (afamitresgene autoleucel) (&#34;TECELRA&#34;), which is the first engineered T-cell therapy for the treatment of a solid tumor cancer approved in the U.S. In July 2025, TECELRA was acquired by US WorldMeds alongside letetresgene autoleucel (&#34;lete-cel&#34;), for people with synovial sarcoma and myxoid liposarcoma, in relation to which a commercial launch was planned for 2026. A third clinical candidate, uza-cel, and the collaboration with Galapagos related to that cell therapy was also assigned to US WorldMeds as part of the transaction. We are working to ensure a smooth transition of TECELRA, lete-cel and uza-cel to US WorldMeds. We have also developed certain pre-clinical assets including our PRAME directed T-cell therapy and our CD-70 directed TRuC therapy. We are looking for strategic options in relation to these assets.Forward-Looking StatementsThis release contains &#34;forward-looking statements&#34; within the meaning of the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended and Section 21E of the Exchange Act. Forward-looking statements address our expected future business, financial performance, financial condition, as well as the results of operations and often contain words such as &#34;anticipate&#34; &#34;believe,&#34; &#34;expect,&#34; &#34;may,&#34; &#34;plan,&#34; &#34;potential,&#34; &#34;will,&#34; and similar expressions. Such statements are based only upon current expectations of Adaptimmune. Reliance should not be placed on these forward-looking statements because they involve certain risks and uncertainties. Such risks and uncertainties could cause our actual results to differ materially from those indicated by such forward-looking statements, and include, without limitation: risks associated with the Company's voluntary delisting from Nasdaq and the effectiveness thereof; the Company's plans and timing with respect to the delisting and deregistration of its ADSs; uncertainties regarding eligibility for and timing of quotation on an OTC market; and the trading of the Company's ADSs following the voluntary delisting of the ADSs from Nasdaq. For a further description of the risks and uncertainties that could cause our actual results to differ materially from those expressed in these forward-looking statements, as well as risks relating to our business in general, we refer you to our Annual Report on Form 10-K filed with the Securities and Exchange Commission for the year ended December 31, 2024, our Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and other filings with the Securities and Exchange Commission. The forward-looking statements contained in this press release speak only as of the date the statements were made and we do not undertake any obligation to update such forward-looking statements to reflect subsequent events or circumstances.Adaptimmune ContactInvestor Relations and Media RelationsChris Hill, Chief Executive Officerir@adaptimmune.comTo view the source version of this press release, please visit https://www.newsfilecorp.com/release/274566</div></div>

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Adaptimmune Therapeutics plc announced changes to its Board and Executive Leadership Team effective November 14, 2025. Chris Hill, previously CFO, is now CEO and Director, succeeding Adrian Rawcliffe. Lawrence Alleva is appointed Chairman, replacing David Mott. The company delisted from Nasdaq and is quoted on OTC Pink. The restructuring follows a transaction with US WorldMeds and aims to maximize asset value while reducing public company costs.

Adaptimmune Announces Changes to Board and Executive Leadership Team