ABSTRACT
Background & Aim: Immunocompromised patients are susceptible to high-risk opportunistic infections and malignant diseases. If available, most antiviral and antifungal drugs are quite toxic, relatively ineffective, and induce resistance in the long term. Methods, Results & Conclusion(s): We have previously demonstrated the safety of adoptive cell therapy for COVID-19 patients with CD45RA negative cells containing SARS-CoV-2-specific T cells from a donor, chosen based on HLA compatibility and cellular response to SARS-CoV-2 peptide pools. After finishing a Phase 2 randomized multicenter clinical trial (RELEASE, NCT04578210), we concluded that the infusion is safe, effective, accelerates lymphocyte recovery and shows hallmarks of an immune response. To use adoptive cell therapy to treat COVID-19 it would be necessary to develop a biobank of living drugs. For that, we examined the immune evolution performing a longitudinal analysis from previously SARS-CoV-2 infected and infection- naive individuals covering 21 months from infection. Cellular responses were maintained over time while humoral responses increased after vaccination but were gradually lost. Therefore, the best donors would be recovered individuals and two months after vaccination. We also evaluated the effect of dexamethasone (current standard of care treatment for COVID-19 and other infections involving lymphopenia) and Interleukin-15 (cytokine involved in T-cell maintenance and survival) on CD45RA negative. Dexamethasone did not alter cell functionality, proliferation or phenotype at a clinical-practice concentration, while interleukin-15 increased the memory T-cell and T-regulatory cell activation state, and interferon gamma release. Furthermore, we applied the adoptive passive transfer of CD45RA negative cells containing pathogen-specific memory T-cells to other infectious diseases characterized by sustained lymphopenia. We infused six immunocompromised patients with Cytomegalovirus, BK virus, Aspergillus, and Epstein-Barr virus lymphoproliferative disease. Patients experienced pathogen clearance, resolution of symptoms and lymphocyte increase. Transient microchimerism was detected in three patients. The use of CD45RA negative cells containing specific memory T cells of a third-party donor for treating severe pathogenic diseases in immunocompromised patients is feasible, safe, and effective, and has an advantage over other cell therapies such as lower costs and a less complex regulatory environment.Copyright © 2023 International Society for Cell & Gene Therapy
ABSTRACT
Background: Adoptive cell immunotherapies for opportunistic virus in immunocompromised patients using haploidentical memory T cells have shown to be safe and effective. Since severe cases of COVID-19 present a dysregulated immune system with T cell lymphopenia and a hyper-inflammatory state we have proposed that a similar strategy could be proven to be efficient for COVID-19 patients. This is a study protocol of an open-label, multicenter, double-arm, randomized, dose-finding phase I/II clinical trial to evaluate the feasibility, safety, tolerability, and efficacy of the administration of a single dose of allogenic SARS-CoV-2 specific memory CD45RA - T cells and Natural Killer (NK) cells in COVID-19 patients with lymphopenia and pneumonia. The aim of the study is to find efficient treatments for patients with moderate/severe COVID-19. Identification of Specific memory T cells and NK cells: i)Memory T Cells: we first determined the existence of SARS-CoV-2 specific T cells within the CD45RA - T memory cells of the blood of convalescent donors. Memory T cells can respond quickly to the infection and provide long-term immune protection to reduce the severity of the COVID-19 symptoms without inducing classically T cell alloreactivity. Also, CD45RA - memory T cells confer protection for other pathogens the donors encountered in their life. ii)NK cells: we determined the phenotype of NK cells after COVID-19 and the main characteristic of SARS-CoV-2 specific NK population in the blood of convalescent donors, as it has been shown for cytomegalovirus infections. Also, NK cells confer protection for other pathogens the donors encountered in their life. Pilot Phase I- Safety, feasibility, and dose escalation: Between September and November 2020 a phase 1, dose-escalation, single-center clinical trial was conducted to evaluate the safety and feasibility of the infusion of CD45RA - memory T cells containing SARS-CoV-2 specific T cells as adoptive cell therapy against moderate/severe cases of COVID-19. Nine participants with pneumonia and/or lymphopenia and with at least one human leukocyte antigen (HLA) match with the donor were infused. The first three subjects received the lowest dose (1x10 5 cells/kg), the next three received the intermediate dose (5x10 5 cells/kg) and the last three received the highest dose (1x10 6 cells/kg) of CD45RA - memory T cells. Clinicaltrials.gov registration: NCT04578210. Findings: All participants' clinical status measured by National Early Warning Score (NEWS) and 7-category point ordinal scales showed improvement six days after infusion. No serious adverse events were reported. Inflammatory parameters were stabilized post-infusion and the participants showed lymphocyte recovery two weeks after the procedure. Donor microchimerism was observed at least for three weeks after infusion in all patients. Interpretation: This study provides preliminary evidence supporting the idea that treatment of COVID-19 patients with moderate/severe symptoms using convalescent SARS-CoV-2 specific CD45RA - memory T cells is feasible and safe. We did not find dose-liming toxicity. The Recommended Phase 2 dose was 1x10 6 CD45RA - T cells. Phase II- Efficacy: Between January 2021 and July 2021 patients have been enrolled based on the matched with the HLA genotype of the convalescent donors and following the protocol inclusion/exclusion criteria. The primary outcome is the incidence of patient recovery at day 14, defined as normalization of fever and oxygen saturation or lymphopenia recovery. Secondary outcomes are the time to normal level of lymphocytes, the proportion of patients showing clinical improvement at day 7, time to first negative SARS-CoV-2 PCR, the incidence of treatment-related adverse events, duration of hospitalization, time to discharge, time to improvement by one category a 7-point ordinal scale or NEWS score, the proportion of patients requiring intensive care unit, and all-cause mortality. In addition, lymphocyte recovery by multiparametric flow cytometry and donor chimerism by real-time PCR in the e perimental arm was monitored weekly during the first month. This study provides preliminary evidence supporting the idea that treatment of COVID-19 patients with moderate/severe symptoms using convalescent CD45RA - memory T cells is safe and feasible. The phase II clinical trial is ongoing to demonstrate efficacy. [Formula presented] Disclosures: Soria: Celgene: Other: Fees;Gilead: Other: Fees;AbbVie: Other: Fees.
ABSTRACT
BACKGROUND: Effective treatments are still needed to reduce the severity of symptoms, time of hospitalization, and mortality of COVID-19. SARS-CoV-2 specific memory T-lymphocytes obtained from convalescent donors recovered can be used as passive cell immunotherapy. METHODS: Between September and November 2020 a phase 1, dose-escalation, single centre clinical trial was conducted to evaluate the safety and feasibility of the infusion of CD45RA- memory T cells containing SARS-CoV-2 specific T cells as adoptive cell therapy against moderate/severe cases of COVID-19. Nine participants with pneumonia and/or lymphopenia and with at least one human leukocyte antigen (HLA) match with the donor were infused. The first three subjects received the lowest dose (1 × 105 cells/kg), the next three received the intermediate dose (5 × 105 cells/kg) and the last three received the highest dose (1 × 106 cells/kg) of CD45RA- memory T cells. Clinicaltrials.gov registration: NCT04578210. FINDINGS: All participants' clinical status measured by National Early Warning Score (NEWS) and 7-category point ordinal scales showed improvement six days after infusion. No serious adverse events were reported. Inflammatory parameters were stabilised post-infusion and the participants showed lymphocyte recovery two weeks after the procedure. Donor microchimerism was observed at least for three weeks after infusion in all patients. INTERPRETATION: This study provides preliminary evidence supporting the idea that treatment of COVID-19 patients with moderate/severe symptoms using convalescent CD45RA- memory T cells is feasible and safe. FUNDING: Clinical Trial supported by Spanish Clinical Research Network PT17/0017/0013. Co-funded by European Regional Development Fund/European Social Fund. CRIS CANCER Foundation Grant to AP-M and Agencia Valenciana de Innovación Grant AVI-GVA COVID-19-68 to BS.
ABSTRACT
Syndrome coronavirus 2 (SARS-CoV-2) pandemic is causing a second outbreak significantly delaying the hope for the virus' complete eradication. In the absence of effective vaccines, we need effective treatments with low adverse effects that can treat hospitalized patients with COVID-19 disease. In this study, we determined the existence of SARS-CoV-2-specific T cells within CD45RA- memory T cells in the blood of convalescent donors. Memory T cells can respond quickly to infection and provide long-term immune protection to reduce the severity of COVID-19 symptoms. Also, CD45RA- memory T cells confer protection from other pathogens encountered by the donors throughout their life. It is of vital importance to resolve other secondary infections that usually develop in patients hospitalized with COVID-19. We found SARS-CoV-2-specific memory T cells in all of the CD45RA- subsets (CD3+, CD4+, and CD8+) and in the central memory and effector memory subpopulations. The procedure for obtaining these cells is feasible, easy to implement for small-scale manufacture, quick and cost-effective, involves minimal manipulation, and has no GMP requirements. This biobank of specific SARS-CoV-2 memory T cells would be immediately available "off-the-shelf" to treat moderate/severe cases of COVID-19, thereby increasing the therapeutic options available for these patients.