An open label, multi-centre, phase I/IIa study evaluating the safety and clinical activity of neo-antigen reactive T cells in patients with advanced non-small cell lung cancer

Inclusion criteria will apply at three timepoints. Inclusion criteria: 1. Patient must be at least 18 years old at the screening visit. 2. Patient must have given written informed consent to participate in the study. 3. Histologically or cytologically confirmed diagnosis of non-small cell lung cancer. 4. Patient is considered medically fit enough to undergo all study procedures and interventions: procedures to procure blood and tumour tissue, including a general anaesthetic if required, and to receive fludarabine, cyclophosphamide and IL-2 at protocol doses and schedules. 5. Patient is considered, in the opinion of the investigator, capable of adhering to the protocol. 6. ECOG Performance status 0-1 7. Adequate organ function, indicated by the following laboratory parameters: a. Haemoglobin > = 10.0 g/dL b. White Blood Cell Count (WBC) > = 3.0x10⁹/L c. Absolute Neutrophil count (ANC) > = 1.5x10⁹/L d. Platelets > = 100x10⁹/L e. PT and APTT < 1.5x ULN (unless receiving therapeutic anticoagulation) f. AST, ALT < = 2.5 x ULN g. Bilirubin < 1.5 x ULN h. Creatinine clearance / estimated GFR > = 50ml/min 8. Patients who are of childbearing potential or have partners of childbearing potential must agree to use a highly effective method of contraception during the study and for at least 6 months after the last dose of IL-2. See Section 4.3 of the protocol for details of acceptable methods of contraception. In addition to 1-8, the following inclusion criteria must be met prior to tissue procurement: 9. To be eligible for the study the patient must fall into one of the following groups: a. Operable locally advanced disease (stage IIIA) who are scheduled to undergo surgery. These patients are not candidates for immediate treatment with ATL001 but may be treated in this protocol at relapse. In these patients the tumour samples will be stored in compliance with regulations to enable future manufacture and treatment with ATL001. b. Relapsed disease following previous primary surgery +/- adjuvant therapy and either sufficient stored tissue for manufacturing of ATL001 or accessible site s of disease suitable for collection of adequate tissue for ATL001 manufacture. c. Late stage (IIIB/IV) newly diagnosed disease who have accessible sites of disease suitable for collection of adequate tissue for ATL001 manufacture. d. Late stage (IIIB/IV) disease who have completed first line chemotherapy, have achieved disease control, and have accessible sites of disease suitable for collection of adequate tissue for ATL001 manufacture. e. Late stage (IIIB/IV) disease who are undergoing or have completed treatment with PD-1/PD-L1 inhibitor, have achieved disease control and have accessible sites of disease suitable collection of adequate tissue for ATL001 manufacture. 10. Anticipated life expectancy > = 6 months at the time of tissue procurement In addition to 1-8, the following inclusion criteria must be met prior to lymphodepletion and treatment with ATL001: 11. Patients must have measurable disease according to RECIST v1.1 criteria prior to lymphodepletion. (If patients have no measurable disease following standard therapy, lymphodepletion and ATL001 treatment may be delayed until there is evidence of measurable disease). 12. Patient is considered will enough to receive ATL001 treatment.

Exclusion criteria will apply at two timepoints. Exclusion criteria: 1. Patients with known CNS metastases. 2. Patients with hepatitis B or C, human immunodeficiency virus infection (HIV1/2), syphilis or HTLVI/II infection. 3. Patients who are non-smokers (have smoked < 100 cigarettes in their lifetime). 4. Patients with active autoimmune disease requiring immunosuppressive treatments. 5. Patients requiring regular treatment with steroids at a dose higher than prednisolone 10 mg/day (or equivalent). 6. Patients with superior vena cava syndrome. 7. Patients with a current or recent history, as determined by the Investigator, of clinically significant, progressive, and/or uncontrolled renal, hepatic, haematological, endocrine, pulmonary, cardiac, gastroenterological or neurological disease. 8. Patients who are pregnant or breastfeeding. 9. Patients who have undergone major surgery in the previous 3 weeks. 10. Patients with an active concurrent cancer or a history of cancer within the past 3 years (except for in situ carcinomas or non-melanomatous skin cancers). 11. Patients with a history of organ transplantation. 12. Patients who have previously received any investigational cell or gene therapies. 13. Patients with contraindications for cyclophosphamide, fludarabine or IL-2 at protocol doses. In addition to 1-13, the following exclusion criteria apply to patients who completed first line therapy prior to study entry: 14. Patients who have received any anti-cancer therapy within the 3 weeks prior to blood procurement. 15. Patients with evidence of disease progression at the first scan after commencing standard first line therapy. In addition to 1-13, the following exclusion criteria apply to all patients prior to lymphodepletion and treatment with ATL001: 16. Patients who have received a live vaccination within the 28 days prior to lymphodepletion. 17. Patients with an active infection requiring antibiotics. 18. Patients who have received any anti-cancer therapy within the past 3 weeks prior to lymphodepletion.