Adaptimmune Therapeutics plc American Depositary Shares

Item 1A. Risk Factors.

Our business has significant risks. You should carefully consider the risk factors set out in Part I, Item 1A Risk Factors of our Annual Report on Form 10-K for the year ended December 31, 2023 and the disclosures and risk factors set out in this Quarterly Report, including our condensed consolidated financial statements and the related notes, before making an investment decision regarding our securities. The risks and uncertainties described are those material risk factors currently known and specific to us that we believe are relevant to our business, results of operations and financial condition. Additional risks and uncertainties not currently known to us or that we now deem immaterial may also impair our business, results of operations and financial condition.

As of and for the period ended JuneSeptember 30, 2024, save as provided below there have been no material changes from the risk factors previously disclosed by us in Part I, Item 1A. Risk Factors of our Annual Report on Form 10-K for the year ended December 31, 2023.

We may not be able to maintain compliance with the continued listing requirements of Nasdaq.

Our busiAmerical Depository Shares (ADSs) are listed on Nasdaq. In order to maintain that listing, we must satisfy minimum financial and other requirements including, without limitation, a requirement that our closing bid price must not fall below $1.00 per ADS for 30 consecutive business is, in part, dependent on days. On November 1, 2024, we received a notice from The Nasdaq Stock Market (Nasdaq) that the Company is not in compliance with Nasdaqs Listing Rule 5450(a)(1), because the minimum bid price of the Companys American Depositary Shares (ADSs) has been below $1.00 per share for 30 consecutive business days (the Notice). The Notice has no immediate effect on the listing or trading of the Companys ADSs on The Nasdaq Global Select Market.

In accordance with Nasdaq Listing Rule 5810(c)(3)(A), the Company has 180 calendar days, or until April 30, 2025, to regain compliance with the minimum bid price requirement. To regain compliance, the suclosing bid price of the Companys ADSs must be at least

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$1.00 per ADS for a minimum of ten ccessful commercialionsecutive business days during this 180 calendar day grace period, unless Nasdaq exercises its discretion to extend this ten-day period. In the event the Company does not regain compliance with the minimum bid price requirement by April 30, 2025, the Company may be eligible for an additional 180 calendar day compliance period if it elects to ransfer to The Nasdaq Capital Market. To qualify, the Company would be required to meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, with the exception of the minimum bid price requirement, and would need to provide written notice of its intention to cure the bid price deficiency during the second compliance period. However, if it appears to Nasdaqs staff that the Company will not be able to cure the deficiency or if the Company is otherwise not eligible, Nasdaq would notify the Company that its securities would be subject to delisting. The Company may appeal any such determination to delist its securities, but there can be no assurance that any such appeal would be successful.

The Company intends to monitor the closing bid price of its ADSs and assess potential actions to regain compliance with Nasdaqs Listing Rule 5450(a)(1). However, there can be no assurance that we will be able to regain compliance with the minimum bid price requirement or that we will otherwise maintain compliance with other Nasdaq listing requirements. If we fail to regain and maintain compliance with the minimum bid price requirement or to meet the other applicable continued listing requirements in the future and Nasdaq decides to delist our ADSs, the delisting could adversely affect the market price and liquidity of our ADSs, reduce our ability to raise additional capital and result in operational challenges and damage to investor relations and market reputation.

Although our financial statements have been prepared on a going concern basis, if we fail to obtain additional financing in the future, this may raise substantial doubt about our ability to continue as a going concern in future reporting periods

As of September 30, 2024, the Company had cash and cash equivalents of $116.7 million, marketable securities of $69.3 million, and stockholders equity of $80.0 million. During the nine months ended September 30, 2024, the Company incurred a net profit of $3.4 million, used cash of $39.0 million from its operating activities, and generated revenues of $174.8 million. The Company has incurred net losses in most periods since inception and it expects to incur operating losses in future periods.

We believe that our Total Liquidity will be sufficient to fund our operations for at least 12 months, based upon our currently anticipated research and development activities and planned restructuring of the company to reduce headcount and expenses. This belief is based on estimates that are subject to risks and uncertainties and may change if actual results, revenue from commercialisation of Tecelra or the currently anticipated costs and cost reductions (including those associated with the restructuring) differ from managements estimates or do not occur within anticipated timeframes.

We must obtain additional capital to continue funding planned operations. There is no assurance that the Company will be able to obtain sufficient additional capital to continue funding its operations or, if we do, that it will be on terms that are favourable to our shareholders. Any future fundraising, if possible, is likely to be highly dilutive to our existing shareholders and may also divert our management from its day-to-day activities.

If the Company fails to obtain additional funding, it may be required to:

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If we fail to obtain additional funding, or in the event that we significantly reduce our ongoing expenditures and operations (including the current restructuring), this may result in an inability to retain key individuals required for our ongoing business and may result in a need to delay or halt ongoing programs or change the nature and scope of such programs. As a result, our business financial condition and results of operations could be materially affected.

Our business is, in part, dependent on the successful commercialization of Tecelra in the United States.

Tecelra received FDA approval in August 2024. Tecelra is a genetically modified autologous T-cell immunotherapy indicated for the treatment of adult patients with unresectable or metastatic synovial sarcoma who have received prior systemic therapy, are positive for HLA-A*02:01P, -A*02:02P, -A*02:03P, or -A*02:06P, and negative for HLA-A*02:05P, and whose tumor expresses the MAGE-A4 antigen as detected by an FDA-approved test. The success of our business, including our ability to finance our company and generate any revenue in the future, will, at this point, depend on the successful commercialization of Tecelra in the U.S. Any failure to successfully commercialize Tecelra in the U.S. would have a material and adverse impact on our business.

The commercial success of Tecelra will depend on a number of factors, including the following:

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These factors, many of which are beyond our control, could cause us to experience significant delays or an inability to obtain regulatory approvals or commercialize Tecelra. While we have obtained regulatory approval of Tecelra in the United States, we may never be able to successfully commercialize Tecelra in the United States or receive regulatory approval of Tecelra outside the United States. Accordingly, we cannot provide assurances as to the revenue obtainable through the sale of Tecelra.

Tecelra is approved under accelerated approval in the United States, and additional confirmatory work is required in order to maintain that approval. Inability to maintain approval or to otherwise meet the requirements imposed by the FDA will have a significant impact on our ability to commercialize Tecelra.

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Tecelra is approved under accelerated approval in the U.S. based on overall response rate and duration of response. Continued approval for this indication is contingent upon verification and description of clinical benefit in a confirmatory trial. Our ability to obtain traditional approval for Tecelra may require the conduction of additional studies and will require ongoing discussions with the FDA. Any additional work required to satisfy the conditions of accelerated approval will require additional finances, and any ability to obtain any additional required capital or equivalent sources of finance may delay or prevent our ability to maintain approval for Tecelra.

As part of the approval of Tecelra, certain post approval requirements apply which, if not satisfied, could impact continued approval of Tecelra.

Tecelra is subject to continuing regulation by the FDA Failure to meet any of these requirements may result in negative consequences including adverse publicity, judicial or administrative enforcement, warning letters from the FDA, mandated corrective advertising or communications with doctors, and civil or criminal penalties.

These requirements include submissions of safety and other postmarketing information and reports, registration and listing, as well as continued compliance with cGMPs and cGCPs for any clinical trials that we conduct post-approval. In addition, the FDA and other regulatory authorities may impose additional restrictions or require amendments to our product label after marketing approval in the event of additional adverse events with our cell therapy or of other adverse events seen with similar cell therapy products.

As part of the approval of Teclera, the FDA has imposed certain Postmarketing Commitments (PMCs) and Postmarketing Requirements (PMRs), including certain requirements to conduct additional studies under proscribed timelines. Failure to conduct these PMCs and PMRs in a timely manner could result in enforcement action from the FDA.

We and our contract manufacturers will be subject to periodic unannounced inspections by the FDA to monitor and ensure compliance with cGMPs. We must also comply with requirements concerning advertising and promotion for any cell therapies for which we obtain marketing approval. Promotional communications with respect to prescription drugs, including biologics, are subject to a variety of legal and regulatory restrictions and must be consistent with the information in the products approved labeling. Thus, we will not be able to promote any cell therapies we develop for indications or uses for which they are not approved.

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The approval of Tecelra is limited to adult patients with unresectable or metastatic synovial sarcoma who have received prior systemic chemotherapy, are positive for HLA-A*02:01P, -A*02:02P, -A*02:03P, or -A*02:06P, and negative for HLA-A*02:05P, and whose tumor expresses the MAGE-A4 antigen.

As is common for initial approval of cancer therapies, Tecelra has been approved by the FDA for use in a limited patient population, who have unresectable or metastatic synovial sarcoma and who have already received prior systemic therapy. As a result, our ability to market Tecelra is generally limited to that patient population.

The use of prior therapies or treatment for synovial sarcoma may reduce the effectiveness of our cell therapies.

This is the first time we as an organization are marketing a product and we have limited experience as a commercial company and have never generated revenue from product sales.

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Tecelra is the first product for which we have obtained FDA approval. As a company we have not yet launched any approved products for commercial sale and have not previously generated any revenue from product sales. Accordingly, we will need to continue to transition from a company with a research and development focus to a company capable of supporting commercial activities. We may not be successful in such a transition. We have recruited experienced commercial and medical affairs teams and we will need to continue to develop those teams and the associated support network in order to supply Tecelra on a commercial basis.

We will have to compete with other pharmaceutical and biotechnology companies to recruit, hire, train, and retain suitably skilled and experienced marketing and sales personnel. This process may result in additional delays in bringing our cell therapies to market or in certain cases require us to enter into alliances with third parties in order to do so. However, there can be no assurance that we will be able to establish or maintain such collaborative arrangements, or even if we are able to do so, that they will result in effective sales forces. Any revenue we receive will depend upon the efforts of such third parties, which may not be successful. We may have little or no control over the efforts of such third parties, and our revenue from cell therapy sales may be lower than if we had commercialized our cell therapies ourselves.

For Tecelra, we are using certain third parties to supplement the internal commercial facing teams. We are also using a third party distributor to supply Tecelra and third parties to provide some of the systems required to supply Tecelra and support patients prescribed with Tecelra. We are reliant on those third parties to provide the services we require in accordance with our planned timelines. If any critical third party supplier fails to provide the services as required that may result in a delay to the commercialization of Tecelra. Any inability on our part to develop inhouse sales and commercial distribution capabilities or to establish and maintain relationships with third-party collaborators that can successfully commercialize any cell therapy in the U.S. or elsewhere will have a materially adverse effect on our business and results of operations.

As a novel cell therapy, Tecelra may not gain market acceptance among physicians, patients, hospitals, cancer treatment centers and others in the medical community, including referral centers.

The use of engineered T-cells and cell therapies more generally as a potential cancer treatment is a recent development and may not become broadly accepted by physicians, patients, hospitals, cancer treatment centers and others in the medical community. For example, the product labelling and prescribing information for Tecelra describe certain limitations of use, adverse events, and warnings and precautions, including a boxed warning related to Cytokine Release Syndrome (CRS), which may be severe or life threatening and which occurred in patients receiving Tecelra in clinical trials. Additional factors will influence whether Tecelra is accepted in the market, including:

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The product labelling and prescribing information for Tecelra includes a boxed warning for CRS as well as other warnings and precautions. As Tecelra is used commercially, the rate and nature of adverse reactions may increase and as afamitresgene autoleucel (afami-cel) is studied in additional indications and populations, toxicities may further limit its development and use.

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Coverage, price flexibility, and reimbursement may be limited or unavailable in certain market segments for Tecelra.

Successful sales of Tecelra may depend on the availability of coverage and adequate reimbursement from third-party payors. In addition, because Tecelra represents a new approach to the treatment of synovial sarcoma, we cannot accurately estimate the potential revenue from Tecelra.

Patients who are provided medical treatment for their conditions generally rely on third-party payors to reimburse all or part of the costs associated with their treatment. Obtaining coverage and adequate reimbursement from governmental healthcare programs, such as Medicare and Medicaid, and commercial payors is critical to new product acceptance. Government authorities and third-party payors, such as private health insurers and health maintenance organizations, decide which drugs and treatments they will cover and the amount of reimbursement. Reimbursement by a third-party payor may depend upon a number of factors, including, but not limited to, the third-party payors determination that use of a product is:

Obtaining coverage and reimbursement approval of Tecelra from a government or other third-party payor is a time consuming and costly process which could require us to provide to the payor supporting scientific, clinical and cost-effectiveness data for the use of our products. Even if we obtain coverage for Tecelra, the resulting reimbursement payment rates might not be adequate for us to achieve or sustain profitability or may require co-payments that patients find unacceptably high. Patients are unlikely to use Tecelra unless coverage is provided and reimbursement is adequate to cover a significant portion of the cost of Tecelra.

In the U.S., no uniform policy of coverage and reimbursement for products exists among third-party payors. Therefore, coverage and reimbursement for products can differ significantly from payor to payor. As a result, the coverage determination process is often a time-consuming and costly process that will require us to provide scientific and clinical support for the use of our cell therapies to each payor separately, with no assurance that coverage and adequate reimbursement will be obtained.

There have been, and likely will continue to be, legislative and regulatory proposals at the foreign, national and state levels directed at broadening the availability of healthcare and containing or lowering the cost of healthcare, including the Affordable Care Act (ACA) or provisions of the Inflation Reduction Act (IRA). Such regulatory changes may bring prescription drug pricing reform or healthcare affordability programs that, for example, seek to lower prescription drug costs by allowing governmental healthcare programs to negotiate prices with drug companies, put an inflation cap on drug prices, and lower out-of-pocket expenses for recipients of governmental healthcare programs. We cannot predict the initiatives that may be adopted in the future.

Tecelra represents a novel approach to treatment of synovial sarcoma that could result in heightened regulatory scrutiny.

Use of Tecelra to treat a patient involves genetically engineering a patients T-cells. This is a relatively novel treatment approach that carries inherent development risks including the following, any of which can result in delays to our ability to provide confirmatory evidence of Tecelras effectiveness:

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Manufacturing and supply of cell therapies is complex, and if we encounter any difficulties in manufacture or supply of Tecelra or our ability to provide supply for confirmatory clinical trials commercial supply of Tecelra could be delayed or stopped.

The process of manufacturing and administering Tecelra is complex and highly regulated. Manufacture requires the harvesting of white blood cells from the patient, isolating certain T-cells from these white blood cells, combining patient T-cells with our lentiviral delivery vector through a process known as transduction, expanding the transduced T-cells to obtain the desired dose, and ultimately infusing the modified T-cells back into the patient. As a result of the complexities, our manufacturing and supply costs are likely to be higher than those at more traditional manufacturing processes and the manufacturing process is less reliable and more difficult to reproduce.

Delays or failures in the manufacture of Tecelra (whether by us, any collaborator or our third party contract manufacturers) may result in a patient being unable to receive Tecelra or a requirement to re-manufacture which itself then causes delays in manufacture for other patients. Any delay or failure or inability to manufacture on a timely basis can adversely affect a patients outcomes and delay the timelines for our confirmatory clinical trials and commercialization. With a commercial product delays or failure to manufacture could additionally lead to claims by patients for reimbursement or damages. Such delays or failure or inability to manufacture can result from:

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We will be subject to ongoing regulatory obligations and continued regulatory review, which may result in significant additional expense as well as significant penalties if we fail to comply with regulatory requirements or experience unanticipated problems with Tecelra.

FDA approval is accompanied by requirements to conduct surveillance to monitor the safety and efficacy of Tecelra.

Later discovery of previously unknown problems with Tecelra, including adverse events of unanticipated severity or frequency, or with our third-party manufacturers or manufacturing processes, or failure to comply with regulatory requirements, may result in, among other things:

The FDAs and other regulatory authorities policies may change, and additional government regulations may be enacted that could adversely impact the approval of Tecelra. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in the U.S. or abroad. If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may lose marketing approval and we may not achieve or sustain profitability.

In addition, FDA has required us to conduct a confirmatory trial to verify the clinical benefit of Tecelra. The results from the confirmatory trial or trials may not support the clinical benefit, which could result in the approval being withdrawn.

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