RESUMO
Efficacy of COVID-19 convalescent plasma (CCP) in COVID-19 pneumonia is uncertain. The CORIPLASM study was an open-label, Bayesian randomised clinical trial evaluating the efficacy of CCP in patients with moderate COVID-19, including immunocompromised patients. Patients hospitalised with COVID-19 and less than 9 days since symptoms onset were assigned to receive 4 units of plasma over 2 days ({approx} 840 ml)(CCP) or usual care alone (UC). Primary outcomes were the proportion of patients with a WHO-Clinical Progression Score (CPS) [≥]6 on the 10-point scale on day (d) 4 and survival without ventilation or additional immunomodulatory treatment by d14. A total of 120 patients were recruited and assigned to CCP (n=60) or UC (n=60), including 22 (CCP) and 27 (UC) immunocompromised patients. Thirteen (22%) patients with CCP had a WHO-CPS [≥]6 at d4 versus 8 (13%) with UC, adjusted odds ratio (aOR) 1.88 [95%CI 0.71 to 5.24]. By d14, 19 (31.6%) patients with CCP and 20 (33.3%) patients with UC had ventilation, additional immunomodulatory treatment or had died. Cumulative incidence of death was 3 (5%) with CCP and 8 (13%) with UC at d14 (aHR 0.40 [95%CI 0{middle dot}10 -1{middle dot}53]), and 7 (12%) with CCP and 12 (20%) with UC at d28 (aHR 0.51 [95%CI 0.20-1.32]). Subgroup analysis indicated that CCP might be associated with a lower mortality in immunocompromised patients (HR 0.37 [95%CI 0.14-0.97]). CCP treatment did not improve early outcomes in patients with moderate COVID-19 but was associated with reduced mortality in the subgroup of immunocompromised patients.
RESUMO
We conducted a cross-sectional study for SARS-CoV-2 anti-S1 IgG prevalence in French blood donors (n=32605), from May-2020 to January-2021. A mathematical model combined seroprevalence with daily number of hospital admissions to estimate the probability of hospitalization upon infection and determine the number of infections while correcting for antibody decay. There was an overall seroprevalence increase over the study period and we estimate that [~]15% of the French population had been infected by SARS-CoV-2 by January-2021. The infection/hospitalization ratio increased with age, from 0.56% (18-30yo) to 6.75% (61-70yo). Half of the IgG-S1 positive individuals had no detectable antibodies 4 to 5 months after infection. The seroprevalence in group O donors (7.43%) was lower (p=0.003) than in A, B and AB donors (8.90%). We conclude, based on seroprevalence data and mathematical modelling, that the overall immunity in the French population before the vaccination campaign started was too low to achieve herd immunity.
RESUMO
Patients with hematological malignancies and COVID-19 display a high mortality rate. In such patients, immunosuppression due to underlying disease and previous specific treatment impair humoral response, limiting viral clearance. Thus, COVID-19 convalescent plasma (CCP) therapy appears as a promising approach through the transfer of neutralizing antibodies specific to SARS-CoV-2. We report the effect of CCP in a cohort of 112 patients with hematological malignancies and COVID-19 and a propensity score analysis on subgroups of patients with B-cell lymphoid disease treated (n=81) or not (n=120) with CCP between 1 May 2020 and 1 April 2021. The overall survival of the whole cohort was 65% [56-74.9] and 77.5% [68.5-87.7] for patients with B-cell neoplasm. Prior anti-CD20 monoclonal antibodies therapy was associated with better overall survival whereas age, high blood pressure, and COVID-19 severity were associated with a poor outcome. After an inverse probability of treatment weighting approach, we observed in anti-CD20-exposed patients with B-cell lymphoid disease a decreased mortality of 63% (95% CI=31%-80%) in the CCP-treated group compared to the CCP-untreated subgroup, confirmed in the other sensitivity analyses. Convalescent plasma may be beneficial in COVID-19 patients with B-cell neoplasm who are unable to mount a humoral immune response.
RESUMO
It is of paramount importance to evaluate the prevalence of both asymptomatic and symptomatic cases of SARS-CoV-2 infection and their antibody response profile. Here, we performed a pilot study to assess the levels of anti-SARS-CoV-2 antibodies in samples taken from 491 pre-epidemic individuals, 51 patients from Hopital Bichat (Paris), 209 pauci-symptomatic individuals in the French Oise region and 200 contemporary Oise blood donors. Two in-house ELISA assays, that recognize the full-length nucleoprotein (N) or trimeric Spike (S) ectodomain were implemented. We also developed two novel assays: the S-Flow assay, which is based on the recognition of S at the cell surface by flow-cytometry, and the LIPS assay that recognizes diverse antigens (including S1 or N C-terminal domain) by immunoprecipitation. Overall, the results obtained with the four assays were similar, with differences in sensitivity that can be attributed to the technique and the antigen in use. High antibody titers were associated with neutralisation activity, assessed using infectious SARS-CoV-2 or lentiviral-S pseudotypes. In hospitalized patients, seroconversion and neutralisation occurred on 5-14 days post symptom onset, confirming previous studies. Seropositivity was detected in 29% of pauci-symptomatic individuals within 15 days post-symptoms and 3 % of blood of healthy donors collected in the area of a cluster of COVID cases. Altogether, our assays allow for a broad evaluation of SARS-CoV2 seroprevalence and antibody profiling in different population subsets.
