This is a phase 1/2a study including 2 parts, phase 1 and phase 2a. The phase 1 part isan open-label, single-arm, dose-escalating study to evaluate the safety and explore thedose limiting toxicity and maximum tolerated dose of a human umbilical cord derivedmesenchymal stem cell product (BX-U001) in severe COVID-19 pneumonia patients with acuterespiratory distress syndrome (ARDS). Qualified subjects after the screening will bedivided into low, medium, or high dose groups to receive a single intravenous infusion ofBX-U001 at the dose of 0.5×10^6, 1.0×10^6, or 1.5×10^6 cells/kg of body weight,respectively. The Phase 2a part is a randomized, placebo-controlled, double-blindclinical trial examining the safety and biological effects of BX-U001 at the appropriatedose selected from phase 1 for severe COVID-19 pneumonia patients with the sameinclusion/exclusion criteria as the phase 1 part.

The overall objective of the study is to evaluate the safety and efficacy of MSC therapycombined with best supportive care in hospitalized patients with COVID-19.

The purpose of this study is to assess the safety and tolerability of the investigationalproduct, SBI-101, in subjects with an infectious etiology of Acute Kidney Injury (AKI).SBI-101 is a biologic/device combination product designed to regulate inflammation andpromote repair of injured tissue using allogeneic human mesenchymal stromal cells.SBI-101 will be integrated into the renal replacement circuit and patients will betreated for up to 24 hours.

Since the 1960s, studies have shown that oral polio vaccine (OPV) may have beneficialnon-specific effects, reducing morbidity and mortality from other infections than polio.Such beneficial non-specific effect have been observed for other live vaccines, includingmeasles, smallpox and BCG vaccine. For BCG, the vaccine for which the mechanism has beenstudied the most, the effects appear to be mediated through the innate immune system. TheCOVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has now caused over 7.1million cases and >400,000 deaths worldwide. As everywhere else, it is anticipated thatin Africa the older part of the population will be at risk of severe COVID-19. OPV iswidely used in Africa, but for children. Both polio and coronavirus are positive-strandRNA viruses, therefore it is likely that they may induce and be affected by common innateimmune mechanisms.In a randomised trial at the Bandim Health Project in Guinea-Bissau, the investigatorswill assess the effect of providing OPV vs no vaccine to 3400 persons above 50 years ofage. The trial will have the power to test the hypothesis that OPV reduces the combinedrisk of morbidity admission or death (composite outcome) by at least 28% over thesubsequent 6 months.

This is a phase I trial followed by a phase II randomized trial. The purpose of phase Istudy is the feasibility of treating patients with acute respiratory distress syndrome(ARDS) related to COVID-19 infection (COVID-19) with cord blood-derived mesenchymal stemcells (MSC). The purpose of the phase II trial is to compare the effect of MSC withstandard of care in these patients. MSCs are a type of stem cells that can be taken fromumbilical cord blood and grown into many different cell types that can be used to treatcancer and other diseases. The MSCs being used for infusion in this trial are collectedfrom healthy, unrelated donors and are stored and grown in a laboratory. Giving MSCinfusions may help control the symptoms of COVID-19 related ARDS.

The data obtained from Covid-19 infections seem to suggest that the immunogenesis ofCovid-19 could in some cases be the result of immune dysregulation. On the other hand,endocrine damage is possible at the tile of Covid-19 infection (mainly thyroid,adrenal,and hypothalamus). These disorders are autoimmune or linked to degeneration.The main objective is to assess the thyroid function (thyrotropic axis) as well as thecorticotropic adrenal function of patients who have had Copvid-19 pneumonia. Thesecondary objectives is to describe the pathophysiological mechanisms of pulmonary andvasculothrombotic involvement of Covid-19

This study aims to determine how long COVID-19 neutralizing antibodies can be detected inan elderly institutionalized population presenting fragility factors.This study also aims to stratify seroconversion by immunological profiles of the elderlypatients residing in the EHPAD. This stratification requires the measurement ofimmunological marker levels already described in immunosenescence and also involved inthe development of certain chronic infectious diseases more common in the elderlypopulation. This analysis will enable the investigators to describe an immunological,clinical and biological profile representing a patient who has developed an immunityagainst COVID 19. It will also help the investigators to understand the differentmechanisms leading to a reduced immune response after a potential administration of avaccine. Finally, it will help describe the immune profiles of elderly residents whopresented with non-severe forms of COVID-19.

A phase 2/3 study to determine the efficacy, safety and immunogenicity of the candidateCoronavirus Disease (COVID-19) vaccine ChAdOx1 nCoV-19 in healthy UK volunteers.

The purpose of this study is to find out if immunization with IMM-101 will reduce theincidence of severe respiratory and COVID-19 infections in cancer patients.

This is a phase 2 multi-center, double-blind, randomized, placebo-control clinical trialwith 200 subjects who have never been infected by COVID-19 (SARS-Cov-2 virus screen testnegative, no blood SARS-Cov-2 IgM and IgG antibodies detected during enrollment) followedby a pilot study of 5 subjects to demonstrate the safety of proposed three-dose regimenof autologous AdMSCs infusions. The 100 study subjects who have previously banked theirAdMSCs with Celltex, will receive three doses of autologous AdMSCs (approximately 200million cells) intravenous infusion every three days. The 100 subjects in the controlgroup who have previously banked their AdMSCs with Celltex will not receive any Celltex'sAdMSC therapy but placebo treatments. All subjects are monitored for safety (adverseevents/severe adverse events), COVID-19 symptoms, SARS-Cov-2 virus test, blood SARS-Cov-2IgM and IgG antibodies tests, blood cytokine and inflammatory (CRP, IL_6, IL-10, TNFα)tests and disease severity evaluation for 6 months after the last dose of AdMSC infusionfor the study group and 6 months after the enrollment for the control group.