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 À 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 £ 10 5 cells/kg), the next three received the intermediate dose (5 £ 10 5 cells/kg) and the last three received the highest dose (1 £ 10 6 cells/ kg) of CD45RA À 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 À 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 Innovaci on Grant AVI-GVA COVID-19-68 to BS.

Tacrolimus (TAC) is highly effective for the prevention of acute organ rejection. However, its clinical use may be challenging due to its large interindividual pharmacokinetic variability, which can be partially explained by genetic variations in TAC-metabolizing enzymes and transporters. The aim of this study was to evaluate the influence of genetic and clinical factors on TAC pharmacokinetic variability in 21 stable pediatric renal transplant patients. This study was nested in a previous Prograf to Advagraf conversion clinical trial. CYP3A5, ABCB1 and two POR genotypes were assessed by real-time PCR. The impact on TAC pharmacokinetics of individual genetic variants on CYP3A5 nonexpressors was evaluated by genetic score. Explicative models for TAC AUC C and C after Advagraf were developed by linear regression. The built genetic scores explain 13.7 and 26.5% of the total AUC and C total variability, respectively. Patients genetic information should be considered to monitorizate and predict TAC exposure.

ACTIV-3/TICO Study Group* Background: Ensovibep (MP0420) is a designed ankyrin repeat protein, a novel class of engineered proteins, under investigation as a treatment of SARS-CoV-2 infection.Objective: To investigate if ensovibep, in addition to remdesivir and other standard care, improves clinical outcomes among patients hospitalized with COVID-19 compared with standard care alone.