Cell Therapy With Treg Cells Obtained From Thymic Tissue (thyTreg) to Control the Immune Hyperactivation Associated With COVID-19 and/or Acute Respiratory Distress Syndrome (THYTECH2)

The investigators developed a GMP protocol to isolate Treg cells from thymic tissue (thyTreg). The thyTreg cells are being evaluated in a Phase I/II clinical trial to evaluate the safety and efficacy of the adoptive transfer of autologous thyTreg to prevent rejection in heart transplant children (NCT04924491), with preliminary results indicating the feasibility and safety of the therapy. In addition, thyTreg cells have shown low immunogenicity in the pre-clinical setting, indicating that allogeneic use of these thyTreg cells (allo-thyTreg) would have a low risk of adverse effects. These thyTreg cells could inhibit an excessive inflammation in SARS-CoV-2 infection, or ameliorate the immunological affection underlying Acute respiratory distress syndrome, improving life-threatening manifestations, restoring immune balance, and protecting affected tissues. This clinical trial is an open-label Sequential Parallel Group Phase I/II study to evaluate the safety and efficacy of allogeneic thymus derived Tregs (thyTreg) (thyTreg) in controlling the immune dysregulation associated with SARS-CoV-2 infection and/or Acute Respiratory Distress Syndrome.

Inclusion Criteria: 1. Patient over 18 to 65 years of age 2. Patient Informed and non-opposed to the research by his medical doctor during hospitalization 3. Patient with clinical, radiological, gasometric and immunological criteria defined as: 1. Acute respiratory failure secondary to acute lung injury of noncardiogenic cause 2. Pulmonary abnormalities compatible with bilateral alveoloinsterstitial infiltrates by chest imaging (radiograph or scan) 3. PaO2/FiO2≤ 300 Presence of at least one of the following markers of inflammation: IL6 \> 40 pg/ml or ferritin \>300 ng/ml or CRP \>3 mg/dl or increasing over the last 24 hours Exclusion Criteria: 1. Pregnancy or breast feeding 2. Body mass index \>35 3. Patients not expected to survive 48 hours after enrolment based on clinical assessment 4. Patients with an extracorporeal respiratory support 5. Neutropenia (absolute neutrophil count \