Business Description

Overview We are a commercial-stage biopharmaceutical company working to redefine the treatment of solid tumor cancers with cell therapies. With the approval by the U.S. Food and Drug Administration (“FDA”) of our first biologics license application (“BLA”) for TECELRA® (afamitresgene autoleucel) (“TECELRA”), which is the first engineered T-cell therapy for the treatment of a solid tumor cancer approved in the U.S., we are now focused on its launch and commercialization. ​ TECELRA is a genetically modified autologous T-cell immunotherapy indicated for the treatment of adults with unresectable or metastatic synovial sarcoma who have received prior chemotherapy, are HLA-A*02:01P, -A*02:02P, -A*02:03P, or -A*02:06P positive and whose tumor expresses the MAGE-A4 antigen as determined by FDA-approved or cleared companion diagnostic devices. This indication is approved under the FDA’s accelerated approval based on overall response rate (“ORR”) and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefits in a confirmatory trial. ​ We are planning commercial launch for our second T-cell immunotherapy, letetresgene autoleucel (“lete-cel”), for people with synovial sarcoma and myxoid liposarcoma in 2026. This product will significantly expand our treatable patient population within our commercial sarcoma franchise with up to $400 million annual peak combined US sales from TECELRA and lete-cel. We estimate that approximately 400 newly diagnosed patients per year are biomarker eligible for TECELRA, and an incremental 600 newly diagnosed synovial sarcoma and myxoid liposarcoma patients per year in the US will be biomarker eligible for lete-cel. ​ In addition to our commercial sarcoma franchise we remain committed to our collaboration with Galapagos which uses our uzatresgene autoleucel (“uza-cel”) candidate manufactured using the Galapagos manufacturing process. A clinical trial authorization to start a Phase 1 trial in head and neck cancer is planned for 2025. ​ All of our products and clinical candidates utilize engineered T-cells designed to find and destroy cancer cells in patients. The T-cells are engineered to recognize particular antigens expressed by the cancer cells and to activate a person’s immune system to fight the cancer they have. Our current products and clinical candidates are personalized treatment options where we take a person’s white blood cells, modify them to express the engineered T-cells and then return those engineered T-cells to the patient. ​ During the fourth quarter of 2024 we announced that we were ceasing further investment in all non-core programs. We are undertaking a reduction in headcount of approximately 29% and a reduction of total operating expenses of approximately 25% (as compared to 2024 operating expenses). As of the end of February 2025, the majority of the headcount reduction has been completed. As part of this restructuring in December 2024, we also announced changes to our executive leadership team. In addition, we are implementing additional cost reduction for our preclinical PRAME and CD70 programs and are evaluating all strategic options to maximize shareholder value. ​ TECELRA and Commercialization ​ We are focused on the commercialization of TECELRA for the treatment of advanced synovial sarcoma and for which we received FDA approval on August 1, 2024. As of March 18, 2025, 20 Authorized Treatment Centers (“ATCs”) are available to initiate the treatment journey for our patients and ten patients have been apheresed. We are confident that our full network of approximately 30 ATCs will be active by the end of 2025, covering an estimated 80% of patients treated in sarcoma centers of excellence. Companion diagnostics for biomarker detection are approved and available and we have adequate manufacturing capacity to meet orders. AdaptimmuneAssist is available to support our patients and Health Care Providers (HCPs). ​ ​ 1 Table of Contents ​ Letetresgene autoleucel (“lete-cel”) ​ Lete-cel targets the NY-ESO antigen and has been in clinical trials (the IGNYTE-ESO trial) for people with synovial sarcoma and myxoid liposarcoma. It is the second product in our sarcoma franchise. Final data for the IGNYTE-ESO trial were reported at the Connective Tissue Oncology Society Annual Meeting (“CTOS”) in November 2024. ​ In January 2025, lete-cel was granted breakthrough therapy designation by the U.S.…