A Randomized Controlled Study Assessing Convalescent Immunoglobulins versus Convalescent Plasma for Hospitalized COVID-19 Patients.

BACKGROUND: It is unknown whether convalescent immunoglobulins (cIgG) are better than convalescent plasma (CP) for COVID-19 patients. METHODS: In this randomized trial we assigned high risk COVID-19 with ≤10 days of symptoms, to receive cIgG or CP. The primary endpoint was improvement on day 14 according to the WHO scale. Secondary endpoints were survival on day 14, and improvement, survival, and percent of ventilated patients on day 28 and treatment response in unvaccinated and vaccinated patients. RESULTS: 319 patients were included; 166 received cIgG, and 153 CP. Median age was 64-66 years. 112 patients (67.5%) in the cIgG and 103 patients (67.3%) in the CP group reached the primary endpoint. Difference between groups was 0.1 (95%CI -10.1-10.4, p=0.026), failing to reach non-inferiority. More patients receiving cIgG improved by day 28 [136 patients (81.9%) and 108 patients (70.6%), respectively, 95% CI 1.9-20.7, p<0.001, for superiority p=0.018)]. 17 patients in the cIgG group (10.2%) and 25 patients (16.3%) in the CP group required mechanical ventilation (p=0.136). 16 (9.6%) and 23 (15%) patients respectively died (p=0.172). More unvaccinated patients improved by day 28 in the cIgG group (84.1% vs. 66.1%, p<0.024) and survival was better in the cIgG group (89.9% vs. 77.4% p=0.066). CONCLUSIONS: cIgG failed to reach the primary non-inferiority endpoint on day 14 but was superior to CP on day 28. Survival and improvement by day 28 in unvaccinated patients treated with cIgG were better. In the face of new variants, cIgG is a viable option for treating COVID-19. TRIAL REGISTRATION NUMBER: My Trials MOH_2021-01-14_009667.

Predictors of reinfection with pre-Omicron and Omicron variants of concern among individuals who recovered from COVID-19 in the first year of the pandemic.

OBJECTIVES: The predictors of SARS-CoV-2 reinfection are unclear. We examined predictors of reinfection with pre-Omicron and Omicron variants among COVID-19-recovered individuals. METHODS: Randomly selected COVID-19-recovered patients (N = 1004) who donated convalescent plasma during 2020 were interviewed between August 2021 and March 2022 regarding COVID-19 vaccination and laboratory-proven reinfection. The sera from 224 (22.3%) participants were tested for antispike (anti-S) immunoglobulin G and neutralizing antibodies. RESULTS: The participants' median age was 31.1 years (78.6% males). The overall reinfection incidence rate was 12.8%; 2.7% versus 21.6% for the pre-Omicron (mostly Delta) versus Omicron variants. Negative associations were found between fever during the first illness and pre-Omicron reinfection: relative risk 0.29 (95% confidence interval 0.09-0.94), high anti-N level at first illness and Omicron reinfection: 0.53 (0.33-0.85), and overall reinfection: 0.56 (0.37-0.84), as well as between subsequent COVID-19 vaccination with the BNT162b2 vaccine and pre-Omicron 0.15 (0.07-0.32), Omicron 0.48 (0.25-0.45), and overall reinfections 0.38 (0.25-0.58). These variables significantly correlated with immunoglobulin G anti-S follow-up levels. High pre-existing anti-S binding and neutralizing antibody levels against the SARS-CoV-2 Wuhan and Alpha strains predicted protection against Omicron reinfections. CONCLUSION: Strong immune responses after the first COVID-19 infection and subsequent vaccination with the BNT162b2 vaccine provided cross-protection against reinfections with the Delta and Omicron variants.

Hospitalized patients with severe COVID-19 during the Omicron wave in Israel - benefits of a fourth vaccine dose.

BACKGROUND: Waning vaccine-immunity and an increased incidence of COVID-19 during the Omicron outbreak led the Israeli Ministry of Health to recommend a fourth dose of BNT162b2 for high-risk individuals. This study assessed the effect of that dose for hospitalized patients with severe/critical, breakthrough COVID-19. METHODS: In this multi-center retrospective cohort study of hospitalized adults with severe/critical COVID-19 in Israel, from 01/15/2022-01/31/2022, cases were divided according to the number of vaccinations received. Poor outcome was defined as mechanical ventilation or in-hospital death, and was compared between 3- and 4-dose vaccinees using logistic regression. RESULTS: Included were 1,049 patients, median age 80 years (IQR 69-87), 51% males. Among them, 394 were unvaccinated, 386 had received 3 doses and 88 4 doses. The 3-dose group was older, had more males and immunosuppression, but with similar outcomes, 49% vs. 51% compared to unvaccinated patients (p = 0.72). Patients after 4 doses were similarly older and immunosuppressed, but had better outcomes compared to unvaccinated patients, 34% vs. 51% (p < 0.01). We examined independent predictors for poor outcome in patients with either 3 or 4 doses, received a median of 161 (IQR 147-168) or 14 (IQR 10-18) days before diagnosis, respectively. Receipt of the fourth dose was associated with protection: OR 0.51 (95%CI 0.3-0.87), as was Remdesivir OR 0.65 (95%CI 0.44-0.96). Male sex, chronic renal failure and dementia were associated with poor outcomes. CONCLUSIONS: Among hospitalized patients with severe/critical breakthrough COVID-19, a recent fourth dose was associated with significant protection against mechanical ventilation or death, compared to three doses.

Invasive Fungal Diseases in Hospitalized Patients with COVID-19 in Israel: A Multicenter Cohort Study.

Highly variable estimates of COVID-19-associated fungal diseases (IFDs) have been reported. We aimed to determine the incidence of clinically important fungal diseases in hospitalized COVID-19 patients during the first year of the pandemic. We performed a multicenter survey of IFDs among patients hospitalized with COVID-19 in 13 hospitals in Israel between February 2020 and May 2021. COVID-19-associated pulmonary mold disease (PMD) and invasive candidiasis (IC) were defined using ECMM/ISHAM and EORTC/MSG criteria, respectively. Overall rates of IC and PMD among patients with critical COVID-19 were 10.86 and 10.20 per 1000 admissions, respectively, with significant variability among medical centers. PMD rates were significantly lower in centers where galactomannan was a send-out test versus centers with on-site testing (p = 0.035). The 30-day mortality rate was 67.5% for IC and 57.5% for PMD. Treatment with an echinocandin for IC or an extended-spectrum azole for PMD was associated with significantly lower mortality rates (adjusted hazard ratio [95% confidence interval], 0.26 [0.07-0.91] and 0.23 [0.093-0.57], respectively). In this multicenter national survey, variable rates of PMD were associated with on-site galactomannan testing, suggesting under-detection in sites lacking this capacity. COVID-19-related IFDs were associated with high mortality rates, which were reduced with appropriate antifungal therapy.

Predictors of mortality in COVID-19 patients treated with convalescent plasma therapy.

Several options to treat hospitalized severe COVID-19 patients have been suggested. The study aimed to describe survival in patients treated with convalescent COVID plasma (CCP) and to identify in-hospital mortality predictors. This prospective cohort study examined data from 112 severe COVID-19 patients hospitalized in the Corona Departments in an acute care hospital who received two units of CCP (at least one of them high-titer). Demographic and medical data was retrieved from the patients' electronic health records (EHR). Possible predictors for in-hospital mortality were analyzed in a univariate analysis and those found to be clinically significant were further analyzed in a multivariable analysis. Median age was 67 years (IQR 55-74) and 66 (58.9%) of them were males. Of them, 20 (17.9%) died in hospital. On multivariable analysis diabetes mellitus (p = 0.004, OR 91.54), mechanical ventilation (p = 0.001, OR 59.07) and lower albumin levels at treatment (p = 0.027, OR 0.74) were significantly associated with increased in-hospital mortality. In our study, in-hospital mortality in patients receiving CCP is similar to that reported for the general population, however certain variables mentioned above were associated with increased in-hospital mortality. In the literature, these variables were also associated with a worse outcome in patients with COVID-19 who did not receive CCP. As evidence points toward a benefit from CCP treatment in immunocompromised patients, we believe the above risk factors can further define COVID-19 patients at increased risk for mortality, enabling the selection of candidates for early treatment in an outpatient setting if possible.

Hospitalised patients with breakthrough COVID-19 following vaccination during two distinct waves in Israel, January to August 2021: a multicentre comparative cohort study.

BackgroundChanging patterns of vaccine breakthrough can clarify vaccine effectiveness.AimTo compare breakthrough infections during a SARS-CoV-2 Delta wave vs unvaccinated inpatients, and an earlier Alpha wave.MethodsIn an observational multicentre cohort study in Israel, hospitalised COVID-19 patients were divided into three cohorts: breakthrough infections in Comirnaty-vaccinated patients (VD; Jun-Aug 2021) and unvaccinated cases during the Delta wave (ND) and breakthrough infections during an earlier Alpha wave (VA; Jan-Apr 2021). Primary outcome was death or ventilation.ResultsWe included 343 VD, 162 ND and 172 VA patients. VD were more likely older (OR: 1.06; 95% CI: 1.05-1.08), men (OR: 1.6; 95% CI: 1.0-2.5) and immunosuppressed (OR: 2.5; 95% CI: 1.1-5.5) vs ND. Median time between second vaccine dose and admission was 179 days (IQR: 166-187) in VD vs 41 days (IQR: 28-57.5) in VA. VD patients were less likely to be men (OR: 0.6; 95% CI: 0.4-0.9), immunosuppressed (OR: 0.3; 95% CI: 0.2-0.5) or have congestive heart failure (OR: 0.6; 95% CI: 0.3-0.9) vs VA. The outcome was similar between all cohorts and affected by age and immunosuppression and not by vaccination, variant or time from vaccination.ConclusionsVaccination was protective during the Delta variant wave, as suggested by older age and greater immunosuppression in vaccinated breakthrough vs unvaccinated inpatients. Nevertheless, compared with an earlier post-vaccination period, breakthrough infections 6 months post-vaccination occurred in healthier patients. Thus, waning immunity increased vulnerability during the Delta wave, which suggests boosters as a countermeasure.

Qualifying coronavirus disease 2019 convalescent plasma donors in Israel.

BACKGROUND AND OBJECTIVES: Passive immunization using investigational COVID-19 convalescent plasma (CCP) is a promising therapeutic strategy and could improve outcome if transfused early and contain high levels of anti-SARS-CoV-2 antibodies. We report the management of a national CCP collection and distribution program in Israel. MATERIALS AND METHODS: From 1 April 2020 to 15 January 2021, 4020 volunteer donors donated 5221 CCP units and 837 (20.8%) donors donated more than once. Anti-nucleocapsid IgG antibodies were determined using chemiluminescent immunoassay method (Abbott). A statistical model based on repeated IgG tests in sequential donations was created to predict the time of antibody decline below sample/cut-off (S/CO) level of 4.0. RESULTS: Ninety-six percent of CCP donors suffered a mild disease or were asymptomatic. Older donors had higher antibody levels. Higher antibody levels (S/CO ≥4) were detected in 35.2% of the donors. Low positive (S/CO ≥1.4-3.99) were found in 37%, and 27.8% had undetectable antibodies (S/CO ≤1.4). The model predicted decrease antibody thresholds of 0.55%/day since the first CCP donation, providing guidance for the effective timing of future collections from donors with high antibody levels. CONCLUSIONS: An efficient CCP collection and distribution program was achieved, based on performing initial and repeated plasma collections, preferably from donors with higher antibody levels, and only antibody-rich units were supplied for therapeutic use. The inventory met the quantity and quality standards of the authorities, enabled to respond to the growing demand of the medical system and provide a product that may contribute to improve prognosis in patients with COVID-19.

The neutralization potency of anti-SARS-CoV-2 therapeutic human monoclonal antibodies is retained against viral variants.

A wide range of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing monoclonal antibodies (mAbs) have been reported, most of which target the spike glycoprotein. Therapeutic implementation of these antibodies has been challenged by emerging SARS-CoV-2 variants harboring mutated spike versions. Consequently, re-assessment of previously identified mAbs is of high priority. Four previously selected mAbs targeting non-overlapping epitopes are now evaluated for binding potency to mutated RBD versions, reported to mediate escape from antibody neutralization. In vitro neutralization potencies of these mAbs, and two NTD-specific mAbs, are evaluated against two frequent SARS-CoV-2 variants of concern, the B.1.1.7 Alpha and the B.1.351 Beta. Furthermore, we demonstrate therapeutic potential of three selected mAbs by treatment of K18-human angiotensin-converting enzyme 2 (hACE2) transgenic mice 2 days post-infection with each virus variant. Thus, despite the accumulation of spike mutations, the highly potent MD65 and BL6 mAbs retain their ability to bind the prevalent viral mutants, effectively protecting against B.1.1.7 and B.1.351 variants.

BNT162b2 vaccine breakthrough: clinical characteristics of 152 fully vaccinated hospitalized COVID-19 patients in Israel.

OBJECTIVES: The mRNA coronavirus disease 2019 (COVID-19) vaccines have shown high effectiveness in the prevention of symptomatic COVID-19, hospitalization, severe disease and death. Nevertheless, a minority of vaccinated individuals might become infected and experience significant morbidity. Characteristics of vaccine breakthrough infections have not been studied. We sought to portray the population of Israeli patients, who were hospitalized with COVID-19 despite full vaccination. METHODS: A retrospective multicentre cohort study of 17 hospitals included patients fully vaccinated with Pfizer/BioNTech's BNT162b2 vaccine who developed COVID-19 more than 7 days after the second vaccine dose and required hospitalization. The risk for poor outcome, defined as a composite of mechanical ventilation or death, was assessed. RESULTS: A total of 152 patients were included, accounting for half of hospitalized fully vaccinated patients in Israel. Poor outcome was noted in 38 patients and mortality rate reached 22% (34/152). Notably, the cohort was characterized by a high rate of co-morbidities predisposing to severe COVID-19, including hypertension (108; 71%), diabetes (73; 48%), congestive heart failure (41; 27%), chronic kidney and lung diseases (37; 24% each), dementia (29; 19%) and cancer (36; 24%), and only six (4%) had no co-morbidities. Sixty (40%) of the patients were immunocompromised. Higher viral load was associated with a significant risk for poor outcome. Risk also appeared higher in patients receiving anti-CD20 treatment and in patients with low titres of anti-Spike IgG, but these differences did not reach statistical significance. CONCLUSIONS: We found that severe COVID-19 infection, associated with a high mortality rate, might develop in a minority of fully vaccinated individuals with multiple co-morbidities. Our patients had a higher rate of co-morbidities and immunosuppression compared with previously reported non-vaccinated hospitalized individuals with COVID-19. Further characterization of this vulnerable population may help to develop guidance to augment their protection, either by continued social distancing, or by additional active or passive vaccinations.

Multi-clonal SARS-CoV-2 neutralization by antibodies isolated from severe COVID-19 convalescent donors.

The interactions between antibodies, SARS-CoV-2 and immune cells contribute to the pathogenesis of COVID-19 and protective immunity. To understand the differences between antibody responses in mild versus severe cases of COVID-19, we analyzed the B cell responses in patients 1.5 months post SARS-CoV-2 infection. Severe, and not mild, infection correlated with high titers of IgG against Spike receptor binding domain (RBD) that were capable of ACE2:RBD inhibition. B cell receptor (BCR) sequencing revealed that VH3-53 was enriched during severe infection. Of the 22 antibodies cloned from two severe donors, six exhibited potent neutralization against authentic SARS-CoV-2, and inhibited syncytia formation. Using peptide libraries, competition ELISA and mutagenesis of RBD, we mapped the epitopes of the neutralizing antibodies (nAbs) to three different sites on the Spike. Finally, we used combinations of nAbs targeting different immune-sites to efficiently block SARS-CoV-2 infection. Analysis of 49 healthy BCR repertoires revealed that the nAbs germline VHJH precursors comprise up to 2.7% of all VHJHs. We demonstrate that severe COVID-19 is associated with unique BCR signatures and multi-clonal neutralizing responses that are relatively frequent in the population. Moreover, our data support the use of combination antibody therapy to prevent and treat COVID-19.

Compassionate use of convalescent plasma for treatment of moderate and severe pneumonia in COVID-19 patients and association with IgG antibody levels in donated plasma.

BACKGROUND: We assessed outcome of patients with moderate and severe COVID-19 following treatment with convalescent plasma (CP) and the association with IgG levels in transfused CP. METHODS: A prospective cohort study. Primary outcome was improvement at day 14 defined as alive, not on mechanical ventilation, and moderate, mild, or recovered from COVID-19. Antibody levels in CP units were unknown at the time of treatment. IgG against the spike protein S1 was subsequently measured by ELISA. Neutralizing antibodies titers were determined in a subset. Outcome was assessed in relation to the mean antibody level transfused to the patients (≤4.0 versus >4.0). FINDINGS: Of 49 patients, 11 (22.4%) had moderate, 38 (77.6%) had severe disease, 28 were ventilated. At day 14, 24 (49.0%) patients improved, 9 (18.4%) died, and 13 (26.5%) were ventilated. In 14/98 (14.3%) CP units IgG was < 1.1 (cutoff calibration) and in 60 (61.2%) ≤4.0. IgG level and neutralizing antibody titer were correlated (0.85 p < 0.001). In patients receiving ≤4.0 antibody levels, 11/30 improved (36.7%) versus 13/19 (68.4%) in patients receiving >4.0 odds ratio (OR) 0.267 [95% confidence interval (CI) 0.079-0.905], P = 0.030. In patients diagnosed >10 days prior to treatment, 4/14 (22.4%) improved in the ≤4.0 antibody group, versus 6/7 (85.7%) in the >4.0 antibody group, OR 0.048 (95% CI, 0.004-0.520), P = 0.007. No serious adverse events were reported. INTERPRETATION: Treatment with CP with higher levels of IgG against S1 may benefit patients with moderate and severe COVID-19. IgG against S1 level in CP predicts neutralization antibodies titers.