This is an open-label multicenter randomized non comparative phase II study to evaluate the safety and efficacy of the monoclonal anti-KIR3DL2 antibody Lacutamab in patients with Refractory/Relapsing (R/R) KIR3DL2 positive Peripheral T Cell Lymphoma (PTCL) : Not Other Specified (NOS), PTCL-TFH (including Angioimmunoblastic T-cell Lymphoma (AITL), Follicular T-cell lymphoma, Nodal peripheral T-cell lymphoma with TFH phenotype), Anaplastic large cell lymphoma (ALCL), Adult T-cell leukemia/lymphoma (ATL), Hepatosplenic T-cell lymphoma (HSTL), Enteropathy-associated T-cell lymphoma (EATL), Monomorphic epitheliotropic intestinal T cell lymphoma (MEITL), NK-T cell lymphoma (NKT) and Aggressive NK-cell leukemia (ANKL).

The design is non comparative meaning that non comparison between arms will be performed as the control arm will ensure that the assumptions used for sample size calculation are verified. For that reason, randomization is unbalanced in favor of the experimental arm (2:1).

Inclusion Criteria:

• 1. KIR3DL2-positive with at least 1% of tumour cells positivity, before randomization, based on central evaluation by immunohistochemistry (IHC) 2. Patients with histologically documented PTCL:

  • Biopsy-proven treated PTCL defined by the WHO 2016 criteria (the biopsy at relapse is recommended but not mandatory):

    • PTCL-NOS
    • PTCL-TFH (AITL, Follicular T-cell lymphoma, Nodal peripheral T-cell lymphoma with TFH phenotype)
    • ALCL
    • ATL: acute- or lymphoma-type
    • HSTL
    • EATL
    • MEITL
    • NKT
    • ANKL 3. For patients with ALCL: previously treated with brentuximab vedotin 4. Relapsed/refractory PTCL after at least one previous line of systemic based regimen of chemotherapy (no mandatory latency after the previous treatment) 5. With a maximum of 2 prior lines of systemic therapies, including autologous stem cell transplantation (ASCT is authorized in first and second line and is not counted as a unique line, even if associated to a systemic therapy) 6. Bi-dimensionally measurable disease defined by at least one single node or tumor lesion ≥ 1.5 cm assessed by CT scan 7. Signed written screening informed consent prior to KIR3DL2 screening 8. Signed written study informed consent prior to randomization 9. Aged 18 years or more with no upper age limit, at randomization 10. Eastern Cooperative Oncology Group (ECOG) performance status 0 to 3 prior to prephase treatment (if applicable), and 0 to 2 prior randomization 11. Minimum life expectancy of 3 months 12. Females of childbearing potential (FCBP) must agree to use highly effective contraceptive method* from C1D1, during the entire study period, during dose interruptions, and for 9 months after the last study treatments 13. FCBP must have a negative serum or urinary pregnancy test within 28 days prior C1D1 14. Male patients and their partner (FCBP) must agree to use two reliable forms of contraception (condom for males and hormonal method for partners) from C1D1, during the entire study period, during dose interruptions, and for 9 months after the last study treatments

Exclusion Criteria:

• 1. Patients with active COVID-19 infection (last positive PCR < 2 weeks before randomization) 2. Patients taking immunotherapy or chemotherapy, except short-term corticosteroids in monotherapy at a cumulated dose equivalent of prednisone ≤ 1mg/kg/day, during 7 consecutive days, within 3 weeks prior to first administration of study drug (C1D1); or prephase treatment given at investigator's discretion before randomization and for maximum 3 weeks (glucocorticosteroids, vepesid (VP16), cyclophosphamide, vincristine and prednisone (COP)) 3. Previous treatment by Gemcitabine or Oxaliplatin 4. Use of any experimental anti-cancer drug therapy within 6 weeks before randomization 5. Contraindication to any drug contained in the study treatment regimen 6. Previous allogenic hematopoietic cell transplantation 7. Positive test results for HIV and Hepatitis C Virus (HCV) (Patients who are positive for HCV antibody must be negative for HCV by PCR to be eligible for study participation) 8. Known active hepatitis B (positive Ag HBs) (if latent Hepatitis B Virus (HBV) (positive anti-HBc), patients have to be treated with Entecavir (Baraclude ®) and HBV PCR should be performed every month to allow antiviral strategy adaptation) 9. Central nervous system or meningeal involvement by lymphoma 10. Any of the following laboratory abnormalities prior randomization:

  • Absolute neutrophil count (ANC) < 1 G/L, unless neutropenia is related to PTCL
  • Platelet count < 75 G/L, unless thrombopenia is related to PTCL
  • Alkaline Phosphatases > 2.5 x upper limit of normal (ULN)
  • Serum Glutamoyl-oxaloacetate Transferase (SGOT) /Alanine aminotransferase (AST) or Serum Glutamate Pyruvate Transaminase (SGPT)/Alanine aminotransferase (ALT) > 2.5 x ULN
  • Bilirubin > 1.5 x ULN, unless SGOT/AST and SGPT/ALT > 2.5 x ULN or bilirubin elevated due to PTCL or hemolysis
  • Calculated creatinine clearance (MDRD or Cockcroft) < 40 mL/min 11. Any significant cardiovascular impairment: New York Heart Association (NYHA) Class III or IV cardiac disease, uncontrolled high blood pressure, unstable angina, myocardial infarction or stroke within the last 6 months from randomization, and cardiac arrhythmia within the last 3 months from randomization 12. Uncontrolled clinically significant intercurrent illness including, but not limited to, diabetes, ongoing active infections. Patients receiving antibiotics for infections that are under control may be included in the study 13. Concurrent malignancy or prior history of malignancies other than lymphoma unless the subject has been free of disease for ≥ 2 years, except early stage cutaneous squamous or basal cell carcinoma, localized prostate cancer, or cervical intraepithelial neoplasia 14. Major surgery within 4 weeks before randomization 15. Pregnant or lactating females