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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22283585

RESUMO

BackgroundMonoclonal antibody and antiviral treatments for COVID-19 disease remain largely unavailable worldwide, and existing monoclonal antibodies may be less active against circulating omicron variants. Although treatment with COVID-19 convalescent plasma (CCP) is promising, randomized clinical trials (RCTs) among outpatients have shown mixed results. MethodsWe conducted an individual participant data meta-analysis from all outpatient CCP RCTs to assess the overall risk reduction for all-cause hospitalizations by day 28 in all participants who had transfusion initiated. Relevant trials were identified by searching MEDLINE, Embase, MedRxiv, WHO, Cochrane Library, and Web of Science from January 2020 to September 2022. ResultsFive included studies from four countries enrolled and transfused 2,620 adult patients. Comorbidities were present in 1,795 (69%). The anti-Spike or virus neutralizing antibody titer range across all trials was broad. 160 (12.2%) of 1315 control patients were hospitalized, versus 111 (8.5%) of 1305 CCP-treated patients, yielding a 3.7% (95%CI: 1.3%-6.0%; p=.001) ARR and 30.1% RRR for all-cause hospitalization. The effect size was greatest in those with both early transfusion and high titer with a 7.6% ARR (95%CI: 4.0%-11.1%; p=.0001) accompanied by at 51.4% RRR. No significant reduction in hospitalization was seen with treatment > 5 days after symptom onset or in those receiving CCP with antibody titers below the median titer. ConclusionsAmong outpatients with COVID-19, treatment with CCP reduced the rate of all-cause hospitalization. CCP may be most effective when given within 5 days of symptom onset and when antibody titer is higher. Key PointsWhile the outpatient COVID-19 randomized controlled trial meta-analysis indicated heterogeneity in participant risk factors and convalescent plasma, the combined CCP efficacy for reducing hospitalization was significant, improving with transfusion within 5 days of symptom onset and high antibody neutralization levels.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22278577

RESUMO

BackgroundThe COVIH study is a prospective SARS-CoV-2 vaccination study in people living with HIV (PLWH). Of the 1154 PLWH enrolled, 14% showed a reduced or absent antibody response after a primary vaccination regimen. As the response to an additional vaccination in PLWH with hyporesponse is unknown, we evaluated whether an additional vaccination boosts immune responses in these hyporesponders. MethodsConsenting hyporesponders received an additional 100 {micro}g of mRNA-1273. Hyporesponse was defined as [≤]300 spike(S)-specific binding antibody units [BAU]/mL. The primary endpoint was the increase in antibodies 28 days after the additional vaccination. Secondary endpoints were the correlation between patient characteristics and antibody response, levels of neutralizing antibodies, S-specific T-cell and B-cell responses, and reactogenicity. ResultsOf the 75 PLWH enrolled, five were excluded as their antibody level had increased to >300 BAU/mL at baseline, two for a SARS-CoV-2 infection before the primary endpoint evaluation and two were lost to follow-up. Of the 66 remaining participants, 40 previously received ChAdOx1-S, 22 BNT162b2, and four Ad26.COV2.S. The median age was 63 [IQR:60-66], 86% were male, pre-vaccination and nadir CD4+ T-cell counts were 650/L [IQR:423-941] and 230/L [IQR:145-345] and 96% had HIV-RNA <50 copies/ml. The mean antibody level before the additional vaccination was 35 BAU/mL (SEM 5.4) and 45/66 (68%) were antibody negative. After the additional mRNA-1273 vaccination, antibodies were >300 BAU/mL in 64/66 (97%) with a mean increase of 4282 BAU/mL (95%CI:3241-5323). No patient characteristics correlated with the magnitude of the antibody response nor did the primary vaccination regimen. The additional vaccination significantly increased the proportion of participants with detectable ancestral S-specific B-cells (p=0.016) and CD4+ T-cells (p=0.037). ConclusionAn additional mRNA-1273 vaccination induced a robust serological response in 97% of the PLWH with a hyporesponse after a primary vaccination regimen. This response was observed regardless of the primary vaccination regimen or patient characteristics.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22273221

RESUMO

BackgroundVaccines can be less immunogenic in people living with HIV (PLWH), but for SARS-CoV-2 vaccinations this is unknown. Methods and FindingsA prospective cohort study to examine the immunogenicity of BNT162b2, mRNA-1273, ChAdOx1-S and Ad26.COV2.S vaccines in adult PLWH, without prior COVID-19, compared to HIV-negative controls. The primary endpoint was the anti-spike SARS-CoV-2 IgG response after mRNA vaccination. Secondary endpoints included the serological response after vector vaccination, anti-SARS-CoV-2 T-cell response and reactogenicity. Between February-September 2021, 1154 PLWH (median age 53 [IQR 44-60], 86% male) and 440 controls (median age 43 [IQR 33-53], 29% male) were included. 884 PLWH received BNT162b2, 100 mRNA-1273, 150 ChAdOx1-S, and 20 Ad26.COV2.S. 99% were on antiretroviral therapy, 98% virally suppressed, and the median CD4+T-cell count was 710 cells/{micro}L [IQR 520-913]. 247 controls received mRNA-1273, 94 BNT162b2, 26 ChAdOx1-S and 73 Ad26.COV2.S. After mRNA vaccination, geometric mean concentration was 1418 BAU/mL in PLWH (95%CI 1322-1523), and after adjustment for age, sex, and vaccine type, HIV-status remained associated with a decreased response (0.607, 95%CI 0.508-0.725). In PLWH vaccinated with mRNA-based vaccines, higher antibody responses were predicted by CD4+T-cell counts 250-500 cells/{micro}L (2.845, 95%CI 1.876-4.314) or >500 cells/{micro}L (2.936, 95%CI 1.961-4.394), whilst a viral load >50 copies/mL was associated with a reduced response (0.454, 95%CI 0.286-0.720). Increased IFN-{gamma}, CD4+, and CD8+T-cell responses were observed after stimulation with SARS-CoV-2 spike peptides in ELISpot and activation induced marker assays, comparable to controls. Reactogenicity was generally mild without vaccine-related SAE. ConclusionAfter vaccination with BNT162b2 or mRNA-1273, anti-spike SARS-CoV-2 antibody levels were reduced in PLWH. To reach and maintain the same serological responses and vaccine efficacy as HIV-negative controls, additional vaccinations are probably required.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21266810

RESUMO

BackgroundConvalescent plasma (CP) for hospitalized patients with COVID-19 has not demonstrated clear benefits. However, data on outpatients with early symptoms are scarce. We aimed to assess whether treatment with CP administered during the first 7 days of symptoms reduced the disease progression or risk of hospitalization of outpatients. MethodsTwo double-blind randomized trials (NCT04621123, NCT04589949) were merged with data pooling starting when <20% of their predefined sample size had been recruited. A Bayesian adaptive individual patient data meta-analysis was implemented. Analyses were done with Bayesian proportional odds and logistic models, where odds ratios (OR)<1.0 indicate a favorable outcome for CP. Fourteen study sites across the Netherlands and Catalonia in Spain participated in the trial. The two studies included outpatients aged [≥]50 years and diagnosed with COVID-19 and symptomatic for [≤]7days. The intervention consisted of one unit (200-300mL) of CP with a predefined minimum level of antibodies. The two primary endpoints were (a) a 5-point disease severity scale (fully recovered by day 7 or not, hospital or ICU admission and death) and (b) a composite of hospitalization or death. ResultsOf 797 patients included, 390 received CP and 392 placebo. At baseline, they had a median age of 58 years, 1 comorbidity, symptoms for 5 days and 93% tested negative for SARS-CoV-2 S-protein IgG antibodies. Seventy-four patients were hospitalized, 6 required mechanical ventilation and 3 died. The OR of CP for an improved disease severity scale was 0.936 (credible interval (CI) 0.667-1.311). The OR for hospitalization or death was 0.919 (CI 0.592-1.416). The effect of CP on hospital admission or death was largest in patients with [≤]5 days of symptoms (OR 0.658, 95% CI 0.394-1.085). CP did not decrease the time to full symptom resolution (p=0.62). ConclusionTreatment with CP of outpatients in the first 7 days of symptoms did not improve the outcome of COVID-19. The possible beneficial effect in patients with [≤]5 days of symptoms requires further study. RegistrationNCT04621123 and NCT04589949 on https://www.clinicaltrials.gov Funding sourceZONMW, the Netherlands, grant number 10430062010001. SUPPORT-E, grant number 101015756 YoMeCorono, www.tomecorono.com The Fight AIDS and Infectious Diseases Foundation with funding from the pharmaceutical company Grifols S.A

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21256531

RESUMO

Quantitative or qualitative differences in immunity may drive and predict clinical severity in COVID-19. We therefore measured modules of serum pro-inflammatory, anti-inflammatory and anti-viral cytokines in combination with the anti-SARS-CoV-2 antibody response in COVID-19 patients admitted to tertiary care. Using machine learning and employing unsupervised hierarchical clustering, agnostic to severity, we identified three distinct immunotypes that were shown post-clustering to predict very different clinical courses such as clinical improvement or clinical deterioration. Immunotypes did not associate chronologically with disease duration but rather reflect variations in the nature and kinetics of individual patients immune response. Here we demonstrate that immunophenotyping can stratify patients to high and low risk clinical subtypes, with distinct cytokine and antibody profiles, that can predict severity progression and guide personalized therapy.

6.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-264630

RESUMO

Effective clinical intervention strategies for COVID-19 are urgently needed. Although several clinical trials have evaluated the use of convalescent plasma containing virus-neutralizing antibodies, the effectiveness has not been proven. We show that hamsters treated with a high dose of human convalescent plasma or a monoclonal antibody were protected against weight loss showing reduced pneumonia and pulmonary virus replication compared to control animals. However, a ten-fold lower dose of convalescent plasma showed no protective effect. Thus, variable and relatively low levels of virus neutralizing antibodies in convalescent plasma may limit their use for effective antiviral therapy, favouring concentrated, purified (monoclonal) antibodies.

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20139857

RESUMO

Structured abstract for full paperO_ST_ABSBackgroundC_ST_ABSAfter recovery from COVID-19, most patients have anti-SARS-CoV-2 neutralizing antibodies. Their convalescent plasma could be an inexpensive and widely available treatment for COVID-19. MethodsThe Convalescent-plasma-for-COVID (ConCOVID) study was a randomized trial comparing convalescent plasma with standard of care therapy in patients hospitalized for COVID-19 in the Netherlands. Patients were randomized 1:1 and received 300ml of plasma with anti-SARS-CoV-2 neutralizing antibody titers of at least 1:80. The primary endpoint was day-60 mortality and key secondary endpoints were hospital stay and WHO 8-point disease severity scale improvement on day 15. ResultsThe trial was halted prematurely after 86 patients were enrolled. Although symptomatic for only 10 days (IQR 6-15) at the time of inclusion, 53 of 66 patients tested had anti-SARS-CoV-2 antibodies at baseline. A SARS-CoV-2 plaque reduction neutralization test showed neutralizing antibodies in 44 of the 56 (79%) patients tested with median titers comparable to the 115 donors (1:160 vs 1:160, p=0.40). These observations caused concerns about the potential benefit of convalescent plasma in the study population and after discussion with the data safety monitoring board, the study was discontinued. No difference in mortality (p=0.95), hospital stay (p=0.68) or day-15 disease severity (p=0.58) was observed between plasma treated patients and patients on standard of care. ConclusionMost COVID-19 patients already have high neutralizing antibody titers at hospital admission. Screening for antibodies and prioritizing convalescent plasma to risk groups with recent symptom onset will be key to identify patients that may benefit from convalescent plasma. Clinicaltrials.gov: NCT04342182

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