Early transfusIon of Convalescent Plasma in Elderly COVID-19 Patients. to Prevent Disease Progression.

Older age is an independent poor outcome predictor among COVID-19 hospitalized patients . Among 72,314 COVID-19 cases, case fatality rate (CFR) was 2.3% in total population, 8% in people aged 70 to 79, and 14.8% in those aged 80 and older. In the whole population, CFR was higher in people with comorbidities, ranging from 5-6% in persons with hypertension, chronic respiratory disease, diabetes or cancer, up to 10% in those with cardiovascular diseases. Sars-CoV-2 seems to be able to induce a functional exhaustion of specified T and NK lymphocyte subpopulations, breaking down antiviral immunity. One possible explanation is that the immune system of elderly people, might be exhausted by chronic stimulation associated with comorbidities and more susceptible to this Sars-CoV-2 effect. As a result, in these patients, the activation of the innate immune system might fail to produce an adequate adaptive response (i.e., virus-specific CD8+ T-cells). This results in persistent self-induced inflammation that eventually causes mortality. The investigators hypothesize that transfusing convalescent plasma (containing neutralizing antibodies) at an early phase of COVID-19 infection could prevent or switch off the persistent inflammatory response elicited by the virus. The objective of this study are: * To demonstrate the superiority of COVID-19 convalescent plasma (CCP) plus standard therapy (ST) over ST alone * To prevent progression of pneumonia in COVID-19 patients aged ≥65 with chronic comorbidities * To decrease viral load * To raise anti-SARS-CoV-2 antibody titer in recipients