A Phase 1 Basket Study Evaluating the Safety and Feasibility of T-Plex, Autologous Customized T Cell Receptor-Engineered T Cells Targeting Multiple Peptide/HLA Antigens in Participants With Antigen-positive Locally Advanced (Unresectable) or Metastatic Solid Tumors

Participants will be screened in a separate screening study, TSCAN-003 (NCT05812027), to assess their HLA type, tumor-associated antigen (TAA) expression and loss of heterozygosity (LOH) status. The results of these tests will be used to determine initial eligibility in this study.

Depending on the genetic type, participants will be assigned to one of the following study groups:

Monotherapy:

• Cohort A: TSC-204-A0201 targeting MAGE-A1 on HLA-A*02:01
• Cohort B: TSC-204-C0702 targeting MAGE-A1 on HLA-C*07:02
• Cohort C: TSC-200-A0201 targeting HPV16 E7 on HLA-A*02:01
• Cohort D: TSC-203-A0201 targeting PRAME on HLA-A*02:01

T-Plex Combination:

• COHORT AB: TSC-204-A0201 + TSC-204-C0702
• COHORT AC: TSC-204-A0201 + TSC-200-A0201
• COHORT BC: TSC-204-C0702 + TSC-200-A0201
• COHORT AD: TSC-204-A0201 + TSC-203-A0201
• COHORT BD: TSC-204-C0702 + TSC-203-A0201
• COHORT CD: TSC-200-A0201 + TSC-203-A0201

Participants will undergo leukapheresis to collect cells to manufacture the TCR-T products. They will then undergo lymphodepletion and receive one or two doses of the TCR-T cell therapy product as a monotherapy or part of a combination of TCR-Ts (referred to as T-Plex combinations in this study).

Inclusion Criteria:

1. Must be at least 18 years.
2. Locally advanced (unresectable) or metastatic solid tumor for which there are no available curative treatment options, after failure of the standard of care systemic therapies for that particular indication.
3. Any solid tumor, including but not limited to non-nasopharyngeal head and neck cancer, non-small cell lung cancer, cutaneous melanoma, cervical cancer, ovarian cancer, anal cancer and genital cancers.
4. Participants must express one of the following HLA types, as assessed by a qualified genomics assay in screening study TSCAN-003: HLA-C*07:02, HLA-A*02:01 and HLA-C*07:02 plus HLA-A*02:01
5. Tumor must express MAGE-A1 and/or PRAME and/or HPV16-E7 as assessed by a qualified IHC or RNA-ISH performed in the last 6 months in screening study TSCAN-003 (NCT05812027).
6. Eastern Cooperative Oncology Group (ECOG) Performance status 0-1 at screening.
7. Participants must be able to understand and be willing to give informed consent; decision-impaired adults may consent with their legally authorized representative.
8. At least 1 measurable lesion per modified Response Evaluation Criteria in Solid Tumors (RECIST) v1.1.
9. Adequate bone marrow and organ function.

Exclusion Criteria:

1. Medical or psychological conditions that would make the participant unsuitable candidate for cell therapy at the discretion of the PI.
2. History of myocardial infarction, cardiac angioplasty or stenting, unstable angina, cardiac arrhythmia requiring antiarrhythmic or procedure, or other clinically significant cardiac disease within 12 months of enrollment
3. History of stroke or transient ischemic attack (TIA) within 12 months of enrollment
4. Systemic corticosteroid therapy >10 mg of prednisone daily or equivalent within 7 days of enrollment
5. History of severe hypersensitivity to fludarabine or cyclophosphamide or study product excipients including human serum albumin, Cryostor (DMSO or Dextran 40), or Plasma-Lyte.
6. Untreated or symptomatic central nervous system (CNS) metastases or cytology proven carcinomatous meningitis.
7. Concurrent receipt of another anti-cancer therapy.
8. Presence of fungal, bacterial, viral, or other infection requiring anti-microbials for management.
9. Tumors that have HLA LOH using a central lab clinical trial assay of HLAs addressed by the monotherapy and/or T-Plex combination TCR-Ts in the protocol and have no available TCR-T options for intact HLAs in the participant's tumor.
10. Participants who regularly require supplemental oxygen.