Evaluation of Convalescent Plasma for Ebola Virus Disease in Guinea

The “Invisible Enemy” SARS-CoV-2: Viral Spread and Drug Treatment

Nowadays, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has become the main subject of the scientific medical world and all World Organizations, causing millions of deaths worldwide. In this review, we have highlighted the context of the Coronavirus disease 2019 (COVID-19) pandemic, how the virus spreads, the symptoms and complications that may occur, and, especially, the drug treatment of viral infection, with emphasis on monoclonal antibodies. While well-known strains such as Alpha, Beta, Gamma, and, especially, Delta have shown an accelerated transmission among the population, the new Omicron variant (discovered on 24 November 2021) indicates more significant infectiousness and the poor efficacy of monoclonal antibody therapy due to mutations on the spike protein receptor-binding domain. With these discoveries, the experiments began, the first being in silico and in vitro, but these are not enough, and in vivo experiments are needed to see exactly the cause of neutralization of the action of these drugs. Following the documentation of the latest medical and scientific research, it has been concluded that there are many chemical molecules that have the potential to treat SARS-CoV-2 infection, but more detailed clinical trials are needed for their use in therapy. In addition, it is important to consider the structure of the viral strain in the administration of treatment.

The Role of Disease Severity and Demographics in the Clinical Course of COVID-19 Patients Treated With Convalescent Plasma

Treatment of patients with COVID-19 using convalescent plasma from recently recovered patients has been shown to be safe, but the time course of change in clinical status following plasma transfusion in relation to baseline disease severity has not yet been described. We analyzed short, descriptive daily reports of patient status in 7,180 hospitalized recipients of COVID-19 convalescent plasma in the Mayo Clinic Expanded Access Program. We assessed, from the day following transfusion, whether the patient was categorized by his or her physician as better, worse or unchanged compared to the day before, and whether, on the reporting day, the patient received mechanical ventilation, was in the ICU, had died or had been discharged. Most patients improved following transfusion, but clinical improvement was most notable in mild to moderately ill patients. Patients classified as severely ill upon enrollment improved, but not as rapidly, while patients classified as critically ill/end-stage and patients on ventilators showed worsening of disease status even after treatment with convalescent plasma. Patients age 80 and over showed little or no clinical improvement following transfusion. Clinical status at the time of convalescent plasma treatment and age appear to be the primary factors in determining the therapeutic effectiveness of COVID-19 convalescent plasma among hospitalized patients.

Convalescent plasma in hospitalized pediatric and obstetric coronavirus disease 2019 (COVID-19) patients

BACKGROUND

Published data on coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) use in children and obstetric patients are limited. We describe a single-center experience of hospitalized patients who received CCP for acute COVID-19.

METHODS

A retrospective review of children 0-18-years-old and pregnant patients hospitalized with laboratory-confirmed acute COVID-19 who received CCP from March 1, 2020 to March 1, 2021 was performed. Clinical and laboratory data were collected to assess the safety of CCP administration. Antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were measured in the CCP products and in patients before transfusion and at various time points post-transfusion. Correlation between the administered SARS-CoV-2 administered versus the SARS-CoV-2 anti-spike immunoglobulin response in patient serum was assessed.

RESULTS

Twenty-two children and ten obstetric patients were eligible. Twelve pediatric and eight obstetric patients had moderate disease and ten pediatric and two obstetric patients had severe disease. Five pediatric patients died. Eighteen of 37 (48.6%) CCP titers that were measured met US Food and Drug Administration (FDA) criteria for high immunoglobulin G (IgG) antibody titer. There were no complications with transfusion. High-titer CCP showed a positive correlation with rise in patient total immunoglobulin levels only in obstetric patients but not in pediatric patients. Among pediatric patients, the median serum antibody level increased over time after transfusion.

CONCLUSIONS

Coronavirus 2019 convalescent plasma was administered safely to our patients. Our study suggested that CCP did not interfere with endogenous antibody production. The antibody titer of CCP correlated with post-transfusion response only in obstetric patients. Randomized trials in pediatric and obstetric patients are needed to further understand how to dose CCP and evaluate efficacy.

Safety and immunogenicity of 2-dose heterologous Ad26.ZEBOV, MVA-BN-Filo Ebola vaccination in children and adolescents in Africa: A randomised, placebo-controlled, multicentre Phase II clinical trial

BACKGROUND

Reoccurring Ebola outbreaks in West and Central Africa have led to serious illness and death in thousands of adults and children. The objective of this study was to assess safety, tolerability, and immunogenicity of the heterologous 2-dose Ad26.ZEBOV, MVA-BN-Filo vaccination regimen in adolescents and children in Africa.

METHODS AND FINDINGS

In this multicentre, randomised, observer-blind, placebo-controlled Phase II study, 131 adolescents (12 to 17 years old) and 132 children (4 to 11 years old) were enrolled from Eastern and Western Africa and randomised 5:1 to receive study vaccines or placebo. Vaccine groups received intramuscular injections of Ad26.ZEBOV (5 × 1010 viral particles) and MVA-BN-Filo (1 × 108 infectious units) 28 or 56 days apart; placebo recipients received saline. Primary outcomes were safety and tolerability. Solicited adverse events (AEs) were recorded until 7 days after each vaccination and serious AEs (SAEs) throughout the study. Secondary and exploratory outcomes were humoral immune responses (binding and neutralising Ebola virus [EBOV] glycoprotein [GP]-specific antibodies), up to 1 year after the first dose. Enrolment began on February 26, 2016, and the date of last participant last visit was November 28, 2018. Of the 263 participants enrolled, 217 (109 adolescents, 108 children) received the 2-dose regimen, and 43 (20 adolescents, 23 children) received 2 placebo doses. Median age was 14.0 (range 11 to 17) and 7.0 (range 4 to 11) years for adolescents and children, respectively. Fifty-four percent of the adolescents and 51% of the children were male. All participants were Africans, and, although there was a slight male preponderance overall, the groups were well balanced. No vaccine-related SAEs were reported; solicited AEs were mostly mild/moderate. Twenty-one days post-MVA-BN-Filo vaccination, binding antibody responses against EBOV GP were observed in 100% of vaccinees (106 adolescents, 104 children). Geometric mean concentrations tended to be higher after the 56-day interval (adolescents 13,532 ELISA units [EU]/mL, children 17,388 EU/mL) than the 28-day interval (adolescents 6,993 EU/mL, children 8,007 EU/mL). Humoral responses persisted at least up to Day 365. A limitation of the study is that the follow-up period was limited to 365 days for the majority of the participants, and so it was not possible to determine whether immune responses persisted beyond this time period. Additionally, formal statistical comparisons were not preplanned but were only performed post hoc.

CONCLUSIONS

The heterologous 2-dose vaccination was well tolerated in African adolescents and children with no vaccine-related SAEs. All vaccinees displayed anti-EBOV GP antibodies after the 2-dose regimen, with higher responses in the 56-day interval groups. The frequency of pyrexia after vaccine or placebo was higher in children than in adolescents. These data supported the prophylactic indication against EBOV disease in a paediatric population, as licenced in the EU.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02564523.

Effectiveness and Controversy of Convalescent Plasma Therapy for Coronavirus Disease 2019 Patients

Since the coronavirus disease 2019 (COVID-19) began to spread, it remains pandemic worldwide. The European Medicines Agency's human medicines committee and Food and Drug Administration have only granted a conditional marketing authorization for remdesivir to treat COVID-19. It is essential to apply other valuable treatments. Convalescent plasma (CP), donated by persons who have recovered from COVID-19, is the cellular component of blood that contains specific antibodies. Therefore, to determine the feasibility of CP for COVID-19, the effectiveness and controversy are discussed in depth here. It is suggested that CP plays a certain role in the treatment of COVID-19. As a treatment, it may have its own indications and contraindications, which need to be further discussed. Meanwhile, it is critical to establish a standard procedure for treatment from CP collection, preservation, transport, to transfusion, and conduct some large sample randomized controlled trials to confirm the transfusion dosage, appropriate time, frequency, and actively prevent adverse outcomes that may occur.

Vaccine-Associated Enhanced Disease and Pathogenic Human Coronaviruses

Vaccine-associated enhanced disease (VAED) is a difficult phenomenon to define and can be confused with vaccine failure. Using studies on respiratory syncytial virus (RSV) vaccination and dengue virus infection, we highlight known and theoretical mechanisms of VAED, including antibody-dependent enhancement (ADE), antibody-enhanced disease (AED) and Th2-mediated pathology. We also critically review the literature surrounding this phenomenon in pathogenic human coronaviruses, including MERS-CoV, SARS-CoV-1 and SARS-CoV-2. Poor quality histopathological data and a lack of consistency in defining severe pathology and VAED in preclinical studies of MERS-CoV and SARS-CoV-1 vaccines in particular make it difficult to interrogate potential cases of VAED. Fortuitously, there have been only few reports of mild VAED in SARS-CoV-2 vaccination in preclinical models and no observations in their clinical use. We describe the problem areas and discuss methods to improve the characterisation of VAED in the future.

The discovery and development of novel treatment strategies for filoviruses

INTRODUCTION

Filoviruses are negative-stranded, enveloped RNA viruses that can cause hemorrhagic fever in humans and include Ebola and Marburg viruses. Lethality rates can reach 90% in isolated outbreaks. The 2013-2016 Ebola virus epidemic demonstrated the global threat of filoviruses and hastened development of vaccines and therapeutics. There are six known filoviruses that cause disease in humans, but still few therapeutics are available for treatment.

AREAS COVERED

This review summarizes identification, testing, and development of therapeutics based on the peer-reviewed scientific literature beginning with the discovery of filoviruses in 1967. Small molecules, antibodies, cytokines, antisense, post-exposure vaccination, and host-targeted therapeutic approaches are discussed. An emphasis is placed on therapeutics that have shown promise in in vivo studies.

EXPERT OPINION

Two monoclonal antibody regimens are approved for use in humans for one filovirus (Ebola virus), and preclinical nonhuman primate studies suggest that other monoclonal-based therapies are likely to be effective against other filoviruses. Significant progress has been made in small-molecule antivirals and host-targeted approaches. An important consideration is the necessity of pan-filovirus therapeutics via broadly effective small molecules, antibody cocktails, and cross-reactive antibodies. The use of filovirus therapeutics as prophylactic treatment or in chronically infected individuals should be considered.

Plasma therapy: a passive resistance against the deadliest

Convalescent plasma therapy provides a useful therapeutic tool to treat infectious diseases, especially where no specific therapeutic strategies have been identified. The ongoing pandemic puts back the spotlight on this age-old method as a viable treatment option. In this review, we discuss the usage of this therapy in different diseases including COVID-19, and the possible mechanisms of action. The current review also discusses the progress of therapeutic applications of blood-derivatives, from the simple transfer of immunized animal sera, to the more target-specific intravenous administration of human immunoglobulins from a pool of convalescent individuals, in both infectious and non-infectious diseases of various etiologies.

Convalescent plasma for treatment of COVID-19: study protocol for an open randomised controlled trial in Sweden

INTRODUCTION

Although there are many studies on the use of convalescent plasma (CP) for treatment of COVID-19, it is not clear (1) which groups of patients may benefit, (2) what dose of plasma to give, or (3) which antibody levels the plasma should contain. Previous phase I/II studies and literature review suggest that CP should only be given to patients with viraemia, that a daily infusion should be given until the patient becomes virus free and that the neutralising antibody titre should preferably be >1:640 METHODS AND ANALYSIS: An open randomised controlled trial enrolling patients with COVID-19, who must be SARS-CoV-2 positive in both airway and blood samples and admitted to a study hospital. Block randomisation 2:1 is to either 200 mL CP (preferably titre ≥1/640) daily for up to 10 days (until virus negative in blood) plus standard care or standard care only (control arm). The primary endpoint is mortality by day 28 after study inclusion. Secondary endpoints include mortality by day 60 and doses of plasma needed to clear viraemia. Assuming a reduced mortality of approximately 30% by the CP therapy and 85%-88% survival in the control arm, approximately 600 participants will be enrolled to the CP therapy arm and 300 participants to the control arm.

ETHICS AND DISSEMINATION

Ethical approval has been granted by the Swedish Ethical Review Authority (reference: 2020-06277). Results from this trial will be compiled in a clinical study report, disseminated via journal articles and communicated to stakeholders.

TRIAL REGISTRATION NUMBER

NCT04649879.

Ebola virus disease in pregnancy: a systematic review and meta-analysis

This review synthesises and appraises evidence on the effects of Ebola virus disease (EVD) in pregnancy. We searched bibliographic databases from dates of inception to November 2020, yielding 28 included studies.

The absolute risk of maternal death associated with EVD was estimated at 67.8% (95% confidence interval [CI] 49.8 to 83.7, I²=85%, p<0.01) and the relative risk of death in pregnant women compared with non-pregnant women was estimated at 1.18 (95% CI 0.59 to 2.35, I²=31.0%, p=0.230). The absolute risk for foetal losses was estimated at 76.9% (95% CI 45.0 to 98.3, I²=96%, p<0.01) and neonatal death was 98.5% (95% CI 84.9 to 100, I²=0.0%, p=0.40). The gap analysis suggests limited or no data on the clinical course, non-fatal perinatal outcomes and EVD management in pregnant women. The review suggests that EVD has a high maternal and perinatal mortality, underscoring the urgent need for preventative and therapeutic solutions and improved screening and follow-up of pregnant women and newborns during outbreaks. There is not enough evidence to conclusively rule out pregnancy as a risk factor for mortality and there is limited evidence on the disease course, outcomes and management of EVD in pregnancy, and this supports the need for robust clinical trials and prospective studies that include pregnant women.

Clinical drug therapies and biologicals currently used or in clinical trial to treat COVID-19

The potential emergence of SARS-CoV-2 variants capable of escaping vaccine-generated immune responses poses a looming threat to vaccination efforts and will likely prolong the duration of the COVID-19 pandemic. Additionally, the prevalence of beta coronaviruses circulating in animals and the precedent they have set in jumping into human populations indicates that they pose a continuous threat for future pandemics. Currently, only one therapeutic is approved by the U.S. Food and Drug Administration (FDA) for use in treating COVID-19, remdesivir, although other therapies are authorized for emergency use due to this pandemic being a public health emergency. In this review, twenty-four different treatments are discussed regarding their use against COVID-19 and any potential future coronavirus-associated illnesses. Their traditional use, mechanism of action against COVID-19, and efficacy in clinical trials are assessed. Six treatments evaluated are shown to significantly decrease mortality in clinical trials, and ten treatments have shown some form of clinical efficacy.

Treatment of SARS-CoV-2 (COVID-19): A safety perspective

The goal of this review is to report a balanced perspective of current evidence for efficacy of treatments for coronavirus disease 2019 (COVID-19) against the historical safety of these treatments as of May 2021. We preselected therapies of interest for COVID-19 based on national guidelines and modified over time. We searched PubMed and Medline for these specific COVID-19 treatments and data related to their efficacy. We also searched for prior randomized controlled trials of each therapy to assess adverse effects, and we obtained the Food and Drug Administration Approval label for this information. Several drugs have been approved for the treatment of COVID-19, and many more are under study. This includes dexamethasone, remdesivir, hydroxychloroquine/chloroquine, lopinvir/ritonavir, interferon or interleukin inhibitors, convalescent plasma and several vitamins and minerals. The strongest evidence for benefit is mortality benefit with dexamethasone in patients with COVID-19 and hypoxemia, although there is a signal of harm if this is started too early. There are several other promising therapies, like interleukin inhibitors and ivermectin. Hydroxychloroquine/chloroquine, lopinvir/ritonavir, and convalescent plasma do not have enough evidence of benefit to outweigh the known risks of these drugs.

Case Report: Serial Cases: Prolongation of High Immunoglobulin G Level in Repetitive COVID-19 Convalescence Plasma Donor in Saiful Anwar Hospital Malang, Indonesia

Background

Convalescent plasma therapy is expected to be a promising alternative to supportive therapy during the SARS-CoV-2 pandemic outbreak. Altered immune response in repetitive convalescent plasma donors has not been widely studied. This case series was reported to analyze the patterns of immune responses and the factors that might influence them in repetitive convalescent plasma donors and increase awareness of COVID-19 survivors to donate their convalescent plasma.

Cases Illustration

There were five repetitive donors who were eligible as convalescent plasma donor requirements. It was found two donors who showed increment of anti-SARS-CoV-2 IgG level after donation and two others who showed persistent anti-SARS-CoV-2 IgG level more than two months after recovered.

Discussion

There was a difference in immune response in survivors who have the probability of being exposed to same antigens with survivors who did not, where the group of survivors who are at risk of exposure to antigens after recovery could trigger anamnestic immune response that can increase antiSARS-CoV-2 IgG levels. The other factor that influence the prolongation of anti-SARS-CoV-2 IgG levels are the possibility of neutralizing antibodies in plasma upregulation.

Conclusion

Immunological phenomenon in SARS-CoV-2, both in survivors and convalescent plasma donors, have not been widely observed and studied. From the case series discussed above, it can be concluded that convalescent plasma donation does not yet have strong evidence of decreasing levels of specific antibodies against SARS-CoV-2 and plasmapheresis procedure is safe to be done without reducing the protective effect of donor antibody post-plasma donation.

Efficacy and Safety of Convalescent Plasma Transfusion Administered as Adjunctive Treatment to Standard Treatment in Moderate, Severe, and/or Critically Ill Patients with COVID-19 in Dr. M. Djamil General Hospital

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a respiratory disease caused by severe acute respiratory syndrome coronavirus 2. High mortality rate due to COVID-19 has become a serious health problem globally. At present, there is no definitive therapy for COVID-19. AIM: The objective of this study is to evaluate convalescent plasma therapy (CPT) in COVID-19 patients. METHODS: The study was conducted in prospective experimental design with sample population of COVID-19 inpatient in Dr. M. Djamil General Hospital, Padang, isolation ward. This study was involving 20 patients consisted of 10 patients of experimental group who received standard therapy and CPT and 10 patients of control group who received standard therapy only; 10 males and 10 females. Differences in laboratory results in both groups were analyzed by T-test or Mann–Whitney U-test. RESULTS: Twenty subjects included in this study with average of age 56.50 (9.606) years. The mean of C-reactive protein (CRP) serum of the experimental group on day 1 (CRP +1) after CPT was 17.50 (25.343) while the control group was 77.50 (75.177) with p = 0.028 (p < 0.05). However, there were no differences in sequential organ failure assessment, hemoglobin, leukocyte, platelet, partial pressure of oxygen, D-dimer, procalcitonin, interleukin-6, lactate dehydrogenase, ferritin, aspartate aminotransferase, alanine aminotransferase, urea, creatinine, glomerular filtration rate, bilirubin, cycle threshold values, and chest X-ray finding between both groups. CONCLUSION: There was a significant difference in CRP +1 between the experimental group and control group, while no significant differences found in other parameters between both groups. As CRP is an inflammatory indicator, CPT showed benefit in reducing inflammation in COVID-19 patient.

Building a better antibody through the Fc: advances and challenges in harnessing antibody Fc effector functions for antiviral protection

Antibodies can provide antiviral protection through neutralization and recruitment of innate effector functions through the Fc domain. While neutralization has long been appreciated for its role in antibody-mediated protection, a growing body of work indicates that the antibody Fc domain also significantly contributes to antiviral protection. Recruitment of innate immune cells such as natural killer cells, neutrophils, monocytes, macrophages, dendritic cells and the complement system by antibodies can lead to direct restriction of viral infection as well as promoting long-term antiviral immunity. Monoclonal antibody therapeutics against viruses are increasingly incorporating Fc-enhancing features to take advantage of the Fc domain, uncovering a surprising breadth of mechanisms through which antibodies can control viral infection. Here, we review the recent advances in our understanding of antibody-mediated innate immune effector functions in protection from viral infection and review the current approaches and challenges to effectively leverage innate immune cells via antibodies.

Donor Screening and Deferral

The maintenance of an adequate and safe blood supply begins with choosing the right donor at the right time. The evolution of donor screening has been shaped by experience, donor satisfaction, and the ever-challenging emergence of relevant infectious diseases. Screening donors has been standardized over the past 6 decades to protect donor and recipient safety. In this review, we outline, define, and simplify the requirements to assess and defer donors with a focus on recent and ongoing changes to provide up to date information on donor qualification and current challenges in maintaining the blood supply.

Kinetics of Neutralizing Antibody Response Underscores Clinical COVID-19 Progression

BACKGROUND

Neutralizing antibody (nAb) response is generated following infection or immunization and plays an important role in the protection against a broad of viral infections. The role of nAb during clinical progression of coronavirus disease 2019 (COVID-19) remains little known.

METHODS

123 COVID-19 patients during hospitalization in Tongji Hospital were involved in this retrospective study. The patients were grouped based on the severity and outcome. The nAb responses of 194 serum samples were collected from these patients within an investigation period of 60 days after the onset of symptoms and detected by a pseudotyped virus neutralization assay. The detail data about onset time, disease severity and laboratory biomarkers, treatment, and clinical outcome of these participants were obtained from electronic medical records. The relationship of longitudinal nAb changes with each clinical data was further assessed.

RESULTS

The nAb response in COVID-19 patients evidently experienced three consecutive stages, namely, rising, stationary, and declining periods. Patients with different severity and outcome showed differential dynamics of the nAb response over the course of disease. During the stationary phase (from 20 to 40 days after symptoms onset), all patients evolved nAb responses. In particular, high levels of nAb were elicited in severe and critical patients and older patients (≥60 years old). More importantly, critical but deceased COVID-19 patients showed high levels of several proinflammation cytokines, such as IL-2R, IL-8, and IL-6, and anti-inflammatory cytokine IL-10 in vivo, which resulted in lymphopenia, multiple organ failure, and the rapidly decreased nAb response.

CONCLUSION

Our results indicate that nAb plays a crucial role in preventing the progression and deterioration of COVID-19, which has important implications for improving clinical management and developing effective interventions.

Severe Acute Respiratory Syndrome Coronavirus 2: Manifestations of Disease and Approaches to Treatment and Prevention in Humans

The coronavirus disease 2019 (COVID-19) pandemic was caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus has challenged civilization and modern science in ways that few infectious diseases and natural disasters have previously, causing globally significant human morbidity and mortality and triggering economic downturns across financial markets that will be dealt with for generations. Despite this, the pandemic has also brought an opportunity for humanity to come together and participate in a shared scientific investigation. Clinically, SARS-CoV-2 is associated with lower mortality rates than other recently emerged coronaviruses, such as SARS-CoV and the Middle East respiratory syndrome coronavirus (MERS-CoV). However, SARS-CoV-2 exhibits efficient human-to-human spread, with transmission often occurring before symptom recognition; this feature averts containment strategies that had worked previ- ously for SARS-CoV and MERS-CoV. Severe COVID-19 disease is characterized by dysregulated inflammatory responses associated with pulmonary congestion and intravascular coagulopathy leading to pneumonia, vascular insults, and multiorgan disease. Approaches to treatment have combined supportive care with antivirals, such as remdesivir, with immunomodulatory medications, including corticosteroids and cytokine-blocking antibody therapies; these treatments have advanced rapidly through clinical trials. Innovative approaches to vaccine development have facilitated rapid advances in design, testing, and distribution. Much remains to be learned about SARS-CoV-2 and COVID-19, and further biomedical research is necessary, including comparative medicine studies in animal models. This overview of COVID-19 in humans will highlight important aspects of disease, relevant pathophysiology, underlying immunology, and therapeutics that have been developed to date.

Antibody and cellular therapies for treatment of covid-19: a living systematic review and network meta-analysis

OBJECTIVE

To evaluate the efficacy and safety of antiviral antibody therapies and blood products for the treatment of novel coronavirus disease 2019 (covid-19).

DESIGN

Living systematic review and network meta-analysis, with pairwise meta-analysis for outcomes with insufficient data.

DATA SOURCES

WHO covid-19 database, a comprehensive multilingual source of global covid-19 literature, and six Chinese databases (up to 21 July 2021).

STUDY SELECTION

Trials randomising people with suspected, probable, or confirmed covid-19 to antiviral antibody therapies, blood products, or standard care or placebo. Paired reviewers determined eligibility of trials independently and in duplicate.

METHODS

After duplicate data abstraction, we performed random effects bayesian meta-analysis, including network meta-analysis for outcomes with sufficient data. We assessed risk of bias using a modification of the Cochrane risk of bias 2.0 tool. The certainty of the evidence was assessed using the grading of recommendations assessment, development, and evaluation (GRADE) approach. We meta-analysed interventions with ≥100 patients randomised or ≥20 events per treatment arm.

RESULTS

As of 21 July 2021, we identified 47 trials evaluating convalescent plasma (21 trials), intravenous immunoglobulin (IVIg) (5 trials), umbilical cord mesenchymal stem cells (5 trials), bamlanivimab (4 trials), casirivimab-imdevimab (4 trials), bamlanivimab-etesevimab (2 trials), control plasma (2 trials), peripheral blood non-haematopoietic enriched stem cells (2 trials), sotrovimab (1 trial), anti-SARS-CoV-2 IVIg (1 trial), therapeutic plasma exchange (1 trial), XAV-19 polyclonal antibody (1 trial), CT-P59 monoclonal antibody (1 trial) and INM005 polyclonal antibody (1 trial) for the treatment of covid-19. Patients with non-severe disease randomised to antiviral monoclonal antibodies had lower risk of hospitalisation than those who received placebo: casirivimab-imdevimab (odds ratio (OR) 0.29 (95% CI 0.17 to 0.47); risk difference (RD) -4.2%; moderate certainty), bamlanivimab (OR 0.24 (0.06 to 0.86); RD -4.1%; low certainty), bamlanivimab-etesevimab (OR 0.31 (0.11 to 0.81); RD -3.8%; low certainty), and sotrovimab (OR 0.17 (0.04 to 0.57); RD -4.8%; low certainty). They did not have an important impact on any other outcome. There was no notable difference between monoclonal antibodies. No other intervention had any meaningful effect on any outcome in patients with non-severe covid-19. No intervention, including antiviral antibodies, had an important impact on any outcome in patients with severe or critical covid-19, except casirivimab-imdevimab, which may reduce mortality in patients who are seronegative.

CONCLUSION

In patients with non-severe covid-19, casirivimab-imdevimab probably reduces hospitalisation; bamlanivimab-etesevimab, bamlanivimab, and sotrovimab may reduce hospitalisation. Convalescent plasma, IVIg, and other antibody and cellular interventions may not confer any meaningful benefit.

SYSTEMATIC REVIEW REGISTRATION

This review was not registered. The protocol established a priori is included as a data supplement.

FUNDING

This study was supported by the Canadian Institutes of Health Research (grant CIHR- IRSC:0579001321).

READERS' NOTE

This article is a living systematic review that will be updated to reflect emerging evidence. Interim updates and additional study data will be posted on our website (www.covid19lnma.com).

Detection of SARS-CoV-2-independent immunoregulatory activity of COVID-19 convalescent plasma

BACKGROUND

Convalescent plasma has emerged as a potential specific treatment for coronavirus disease 2019 (COVID-19), since it contains severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies. Several studies are currently investigating the efficacy of convalescent plasma for treatment of COVID-19, with a focus on neutralizing antibodies. However, there is little information on whether convalescent plasma may contain additional immunoregulatory constituents produced by the blood donor during convalescence. Therefore, using a standardized whole blood assay employing synthetic toll-like receptor (TLR) ligands, we have investigated the immunoregulatory capacity of convalescent plasma in direct comparison to ABO-matched allogeneic control plasma.

STUDY DESIGN AND METHODS

Whole blood samples from healthy blood donors were collected, and autologous plasma was replaced by convalescent plasma or ABO-matched control plasma. Standardized innate immune triggering and monitoring was performed by adding different TLR ligands (Pam3CsK4 [TLR1/2], HKLM [TLR2], LPS [TLR4], flagellin [TLR5], ssRNA40 [TLR8], imiquimod [TLR7], and FSL-1 [TLR2/6]) and subsequent quantitative analysis of pro- and anti-inflammatory cytokines (IP-10, IL-1β, TNF-α, MCP-1, IL-6, IL-10, and IFN-γ) by cytometric bead array. Negative controls included unstimulated samples as well as samples spiked with autologous plasma.

RESULTS

COVID-19 convalescent plasma (CCP) significantly decreased pro-inflammatory cytokines production triggered by different TLR ligands in healthy donors as compared with healthy control plasma. IL-6, MCP-1, and IFN-γ represented the cytokines that are most frequently downregulated by convalescent plasma.

CONCLUSION

Our experiments reveal a potential novel, SARS-CoV-2-independent immunomodulatory activity of CCP, which may be beneficial for COVID-19 patients.

Filovirus Neutralising Antibodies: Mechanisms of Action and Therapeutic Application

Filoviruses, especially Ebola virus, cause sporadic outbreaks of viral haemorrhagic fever with very high case fatality rates in Africa. The 2013–2016 Ebola epidemic in West Africa provided large survivor cohorts spurring a large number of human studies which showed that specific neutralising antibodies played a key role in protection following a natural Ebola virus infection, as part of the overall humoral response and in conjunction with the cellular adaptive response. This review will discuss the studies in survivors and animal models which described protective neutralising antibody response. Their mechanisms of action will be detailed. Furthermore, the importance of neutralising antibodies in antibody-based therapeutics and in vaccine-induced responses will be explained, as well as the strategies to avoid immune escape from neutralising antibodies. Understanding the neutralising antibody response in the context of filoviruses is crucial to furthering our understanding of virus structure and function, in addition to improving current vaccines & antibody-based therapeutics.

Therapeutics development for Ebola virus disease: A recent scenario

The Ebola virus disease is a deadly pathogenic disease caused by the Ebola virus. It has been observed that this disease causes a high case-fatality rate. Several species of this virus were detected from the genus Ebola virus. Among them, four species of this virus (Ebola, Taï Forest, Sudan, and Bundibugyo) caused disease in humans. Scientists are now focusing on the various therapeutic developments for the treatment of this disease. This article has attempted to depict the development of the entire therapeutic scenario of this disease. In addition, the article tried to illustrate the developmental strategy of the different therapeutics such as small-molecule inhibitors, small interfering RNAs, antibodies, ion channel inhibitors, interferons, and combination therapy against Ebola virus disease. Presently, two monoclonal antibodies (REGN-EB3 and mAb114) showed better efficacy in the Pamoja tuLinde Maisha trial and received approval from the United States Food and Drug Administration. However, scientists should focus on developing more economic therapeutics.

A Multiclass, Multiproduct Covid-19 Convalescent Plasma Donor Equilibrium Model

In this paper, we develop a multiclass, multiproduct equilibrium model for convalescent plasma donations in the Covid-19 pandemic. The potential donors are situated at different locations and the donor population at each location can be separated into different classes based on their motivation and the product for which they provide donations at a collection site. The model captures the competition between nonprofit and for-profit organizations seeking convalescent plasma donations, which is a characteristic of this new market. A variational inequality formulation of the equilibrium conditions and qualitative properties of the model are provided. We also present a capacitated version of the model. Numerical examples of increasing complexity are presented and solved using the modified projection method. The results reveal multiclass, multiproduct donor behavior under different scenarios which can inform policy makers during this pandemic and beyond.

Novel coronavirus disease (COVID-19): origin, transmission through the environment, health effects, and mitigation strategies-a review

The novel coronavirus disease (COVID-19), caused by severe acute respiratory coronavirus-2 (SARS-CoV-2), was first identified in China and subsequently spread globally, resulting in a severe pandemic, and officially declared a significant health emergency by World Health Organization (WHO). Genetic analysis of coronavirus isolated from bats, snakes, and Malay pangolins suggested that they could be intermediate hosts for SARS-CoV-2. The transfer of virus from person to person has been confirmed widely, while the actual source of origin is still unknown. COVID-19 is a highly contagious and infectious disease, and the worldwide transmission of coronavirus has intense effects on the lives of human beings. The spread of the virus is observed mainly through close contact with the infected person due to coughing, sniffing or indirectly through the contaminated surfaces. If people touch contaminated surfaces through their hands, mouth, nose, or eye, it enters the body and causes disease. Also, the virus may transmit through air droplets, water, food, fecal-oral transmission, etc. The infection of virus in human beings could be detected by direct symptoms, or different diagnostic tools are available to determine the viral load. Various safety measures are used to contain the virus, including disinfectants, antiviral drugs, vaccines, wearing masks, social distancing, etc. In the present review, we have focused on transmission of COVID-19 through air and wastewater as environmental transmission modes. We have also discussed the origin of the virus, its mode of action, host immune response, vulnerability, varying symptoms and diagnosis, prevention and control. Further, we have discussed the various treatment options to cope with this viral outbreak.

Graphical abstract

Characterization of an Anti-Ebola virus Hyperimmune Globulin Derived from Convalescent Plasma

BACKRGOUND

Convalescent plasma has been used to treat many viral diseases including Ebola. The manufacture of a purified anti-Ebola virus (EBOV) intravenous immunoglobulin (IVIG) from pooled convalescent plasma is described in this paper.

METHODS

An ELISA targeting an EBOV surface glycoprotein antigen was used to determine the immunoglobulin titer of pooled plasma and purified anti-EBOV IVIG. Anti-EBOV IVIG was also tested in neutralization assays using a vesicular stomatitis virus pseudovirion expressing EBOV glycoprotein on its surface and with live EBOV. Finally, the efficacy of the anti-EBOV IVIG was assessed in a mouse model of EBOV infection.

RESULTS

In the ELISA, the anti-EBOV IVIG was shown to have a seven-fold increase in IgG titer over pooled convalescent plasma. In both the pseudovirion and live virus assays, the anti-EBOV IVIG showed approximately five- to six-fold increased potency over pooled plasma. Anti-EBOV IVIG also significantly improved survivability in mice infected with the virus when administered concurrently or two days after infection.

CONCLUSIONS

These data support this purified anti-EBOV IVIG merits additional investigation and clinical trials for treatment and post-exposure prophylaxis of Ebola virus disease. The experience gained can be applied to manufacture hyperimmune globulins against other emerging viruses.

Perspectives on passive antibody therapy and peptide-based vaccines against emerging pathogens like SARS-CoV-2

The current epidemic of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is raising awareness of the need to act faster when dealing with new pathogens. Exposure to an emerging pathogen generates an antibody response that can be used for preventing and treating the infection. These antibodies might have a high specificity to a target, few side effects, and are useful in the absence of an effective vaccine for treating immunocompromised individuals. The approved antibodies against the receptor-binding domain (RBD) of the viral spike protein of SARS-CoV-2 (e.g., regdanvimab, bamlanivimab, etesevimab, and casirivimab/imdevimab) have been selected from the antibody repertoire of B cells from convalescent patients using flow cytometry, next-generation sequencing, and phage display. This encourages use of these techniques especially phage display, because it does not require expensive types of equipment and can be performed on the lab bench, thereby making it suitable for labs with limited resources. Also, the antibodies in blood samples from convalescent patients can be used to screen pre-made peptide libraries to identify epitopes for vaccine development. Different types of vaccines against SARS-CoV-2 have been developed, including inactivated virus vaccines, mRNA-based vaccines, non-replicating vector vaccines, and protein subunits. mRNA vaccines have numerous advantages over existing vaccines, such as efficacy, ease of manufacture, safety, and cost-effectiveness. Additionally, epitope vaccination may constitute an attractive strategy to induce high levels of antibodies against a pathogen and phages might be used as immunogenic carriers of such peptides. This is a point worth considering further, as phage-based vaccines have been shown to be safe in clinical trials and phages are easy to produce and tolerate high temperatures. In conclusion, identification of the antibody repertoire of recovering patients, and the epitopes they recognize, should be an attractive alternative option for developing therapeutic and prophylactic antibodies and vaccines against emerging pathogens.

Novel quinolone derivatives targeting human dihydroorotate dehydrogenase suppress Ebola virus infection in vitro

Ebola virus (EBOV) has emerged as a significant public health concern since the 2013-2016 outbreak in West Africa. Currently, no effective antiviral treatments have been approved for clinical use. Compound 1 RYL-634 is a quinolone-derived compound that can inhibit dihydroorotate dehydrogenase, a rate-limiting enzyme in the de novo pyrimidine synthesis pathway and it exhibited antiviral activity against multiple RNA virus infection. In this study, we evaluated the efficacy of a panel of newly developed compounds based on RYL-634 against EBOV infection. Our data showed that RYL-634 as well as its derivatives are effective against EBOV transcription- and replication-competent virus-like particle (trVLP) infection and authentic EBOV infection in vitro at low nanomolar IC₅₀ values and relatively high CC₅₀. Of note, the new derivative RYL-687 had the lowest IC₅₀ at approximately 7 nM and was almost 6 times more potent than remdesivir (GS-5734). Exogenous addition of different metabolites in the pyrimidine de novo synthesis pathway confirmed DHODH as the target of RYL-687. These data provide evidence that such quinolone-derived compounds are promising therapeutic candidates against EBOV infection.

US Food and Drug Administration (FDA) Emergency Use Authorization: Glass Half Full or Glass Half Empty?

Recently, the US Food and Drug Administration (FDA) issued emergency use authorization (EUA) for convalescent plasma (CP) for the treatment of hospitalized patients with coronavirus disease 2019 based on a non-peer-reviewed, open-label, observational study. Issuance of an EUA without a proven randomized, controlled trial (RCT) sets a dangerous precedent since the premature action drives healthcare providers and patients away from RCTs that are essential for determining the efficacy and safety of CP. More caution should have been taken based on what was learned from the recent debacle related to the rescinded EUA of hydroxychloroquine and chloroquine, which were approved initially based on an anecdotal report. The FDA process for determining efficacy and safety must be based solely on data from RCTs in order to sustain public and professional trust for future treatment and vaccine efforts to be successful.

COVID-19 convalescent plasma cohort study: Evaluation of the association between both donor and recipient neutralizing antibody titers and patient outcomes

Background

Current evidence regarding COVID‐19 convalescent plasma (CCP) transfusion practices is limited and heterogeneous. We aimed to determine the impact of the use of CCP transfusion in patients with previous circulating neutralizing antibodies (nAbs) in COVID‐19.

Methods

Prospective cohort including 102 patients with COVID‐19 transfused with ABO compatible CCP on days 0–2 after enrollment. Clinical status of patients was assessed using the adapted World Health Organization (WHO) ordinal scale on days 0, 5, and 14. The nAbs titration was performed using the cytopathic effect‐based virus neutralization test with SARS‐CoV‐2 (GenBank MT126808.1). The primary outcome was clinical improvement on day 14, defined as a reduction of at least two points on the adapted WHO ordinal scale. Secondary outcomes were the number of intensive care unit (ICU)‐free days and the number of invasive mechanical ventilation‐free days.

Results

Both nAbs of CCP units transfused (p < 0.001) and nAbs of patients before CCP transfusions (p = 0.028) were associated with clinical improvements by day 14. No significant associations between nAbs of patients or CCP units transfused were observed in the number of ICU or mechanical ventilation‐free days. Administration of CCP units after 10 days of symptom onset resulted in a decrease in ICU‐free days (p < 0.001) and mechanical ventilation‐free days (p < 0.001).

Conclusion

Transfusion of high titer nAbs CCP units may be a determinant in clinical strategies against COVID‐19. We consider these data as useful parameters to guide future CCP transfusion practices.

COVID-19 Pandemic and the Convalescent Plasma Therapy: Possible Benefits and Risks

Purpose of Review

COVID-19 pandemic has been the major threat to the global public health for a year (last of 2019-till date); and unfortunately, there is still as no specific antiviral agent which can be effectively used against this disease curation. Present review focused on the application of the convalescent plasma (CP) therapy as a quick remediation of the disease severity.

Recent Findings

While several drugs have been repurposed based on a number of completed clinical trials together with a huge ongoing effort to develop appropriate vaccine against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the therapeutic approach of the CP therapy appears to be one of the effective methods to rescue the severely affected COVID-19 patients. Such a therapy based on passive immunity evolved from the SARS-CoV-2-infected patients who have fully recovered from COVID-19; and hence these individuals are quite likely to possess high titers of the SARS-CoV-2-neutralizing immunoglobulins (antibodies). However, there are some risks such therapy, and its effectivity also appeared doubtful in some cases. Thus, the current review discussed the issues raised by the administration of such plasma into the SARS-CoV-2-infected individuals.

Summary

Application of CP therapy has been conducted since long time; and for the mitigation of COVID-19 severity, such pharmaceutical strategy is also being employed in spite of several risks which actually can be monitored as well as optimized in order to combat the SARS-CoV-2 infection.

Neutralizing Antibody Responses to SARS-CoV-2 in Korean Patients Who Have Recovered from COVID-19

PURPOSE

Neutralizing antibodies (NAbs) have been considered effective in preventing and treating viral infections. However, until now, the duration and clinical implications of antibody-mediated nature immunity in Koreans have remained unknown. Therefore, we examined NAbs levels and clinical characteristics in recovered coronavirus disease 2019 (COVID-19) patients.

MATERIALS AND METHODS

Blood samples were collected from 143 adult patients who had been diagnosed with and had recovered from COVID-19 from February to March in 2020 at a tertiary-care university-affiliated hospital in Daegu, Korea. A plaque reduction neutralization test was conducted to analyze NAb titers. Individualized questionnaires were used to identify patient clinical information.

RESULTS

The median number of days from symptom onset to the blood collection date was 109.0 (104.0; 115.0). The NAb titers ranged from 10 to 2560. The median NAb titer value was 40. Of the 143 patients, 68 (47.6%) patients had NAb titers ≥80, and 31 (21.7%) patients had NAb titers ≥160. The higher the age or disease severity, the higher the NAb titer. In univariate logistic regression, statistically significant predictors of high NAb titers (≥80) were age, myalgia, nausea or vomiting, dyspnea, and disease severity (p<0.05). Multivariable logistic regression showed that age ≥50 years (p=0.013) and moderate or higher disease severity (p<0.001) were factors associated with high NAb titers (≥80). None of the patients had reinfection of COVID-19.

CONCLUSION

All recovered patients were found to have NAbs regardless of the NAb titers maintained by natural immunity. Age and disease severity during COVID-19 infection were associated with high NAb titers.

Case Report: Effects of Anti-SARS-CoV-2 Convalescent Antibodies Obtained With Double Filtration Plasmapheresis

Passive antibody therapy has been used to treat outbreaks of viral disease, including the ongoing pandemic of severe respiratory acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) or COVID-19. However, the real benefits of the procedure are unclear. We infused a concentrated solution of neutralizing anti-SARS-CoV-2 antibodies obtained from a convalescent donor with a single session of double filtration plasmapheresis (DFPP) into a 56-year-old woman with long history of unremitting, severe COVID-19. She was unable to establish an adequate antiviral immune response because of previous chemotherapy, including the infusion of the anti-CD20 monoclonal antibody rituximab, administered to treat a diffuse large B-cell lymphoma. The disease promptly recovered despite evidence of no endogenous anti-SARS-CoV-2 antibody production. The observation that passive antibody therapy might prove particularly effective in immunodepressed COVID-19 patients requires evaluation in prospective randomized controlled trial.

Antibody responses to filovirus infections in humans: protective or not?

Disease outbreaks caused by Ebola virus and other filoviruses highlight the urgent need for an in-depth understanding of the role of antibody responses in recovery. In this Personal View we aim to discuss the controversial biological role of antibodies during natural filovirus infections in humans. Survival during natural human filovirus infections correlates with the magnitude of the process of antibodies binding to the filovirus glycoprotein and neutralising the virus. Despite the severity of the disease, highly potent monoclonal antibodies have been isolated from survivors of natural filovirus infections, suggesting that the magnitude of the antibody response is insufficient for prevention of severe disease. Unlike natural infections, filovirus vaccines, which express the viral glycoprotein, do induce protective concentrations of antibodies, albeit only when administered at very high doses. Multiple mechanisms by which filoviruses can delay and reduce the antibody response have been identified in the past decade. Furthermore, subneutralising antibody concentrations have been shown to enhance filovirus infections of immune cells bearing Fc receptors. Understanding the role of antibody responses during natural filovirus infections is important for the development of safe and potent vaccines and antibody-based treatments.

Modeling within-Host SARS-CoV-2 Infection Dynamics and Potential Treatments

The goal of this study was to develop a mathematical model to simulate the actions of drugs that target SARS-CoV-2 virus infection. To accomplish that goal, we have developed a mathematical model that describes the control of a SARS-CoV-2 infection by the innate and adaptive immune components. Invasion of the virus triggers the innate immunity, whereby interferon renders some of the target cells resistant to infection, and infected cells are removed by effector cells. The adaptive immune response is represented by plasma cells and virus-specific antibodies. The model is parameterized and then validated against viral load measurements collected in COVID-19 patients. We apply the model to simulate three potential anti-SARS-CoV-2 therapies: (1) Remdesivir, a repurposed drug that has been shown to inhibit the transcription of SARS-CoV-2, (2) an alternative (hypothetical) therapy that inhibits the virus' entry into host cells, and (3) convalescent plasma transfusion therapy. Simulation results point to the importance of early intervention, i.e., for any of the three therapies to be effective, it must be administered sufficiently early, not more than a day or two after the onset of symptoms. The model can serve as a key component in integrative platforms for rapid in silico testing of potential COVID-19 therapies and vaccines.

Molecular mechanism of interaction between SARS-CoV-2 and host cells and interventional therapy

The pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has resulted in an unprecedented setback for global economy and health. SARS-CoV-2 has an exceptionally high level of transmissibility and extremely broad tissue tropism. However, the underlying molecular mechanism responsible for sustaining this degree of virulence remains largely unexplored. In this article, we review the current knowledge and crucial information about how SARS-CoV-2 attaches on the surface of host cells through a variety of receptors, such as ACE2, neuropilin-1, AXL, and antibody-FcγR complexes. We further explain how its spike (S) protein undergoes conformational transition from prefusion to postfusion with the help of proteases like furin, TMPRSS2, and cathepsins. We then review the ongoing experimental studies and clinical trials of antibodies, peptides, or small-molecule compounds with anti-SARS-CoV-2 activity, and discuss how these antiviral therapies targeting host-pathogen interaction could potentially suppress viral attachment, reduce the exposure of fusion peptide to curtail membrane fusion and block the formation of six-helix bundle (6-HB) fusion core. Finally, the specter of rapidly emerging SARS-CoV-2 variants deserves a serious review of broad-spectrum drugs or vaccines for long-term prevention and control of COVID-19 in the future.

Convalescent plasma therapy for severe Covid-19 in patients with hematological malignancies

BACKGROUND

Data on convalescent plasma therapy (CPT) in patients of hematological malignancies with severe Covid-19 is scarce.

OBJECTIVE

To study 14-day mortality in patients who received CPT.

PATIENTS & METHODS

Retrospective multicentre observational study conducted in 4 centres treating haematological malignancies across Delhi-national capital region. Total 33 haematological malignancies patients with severe Covid-19 who received CPT were analysed.

RESULTS

The median age of the study cohort was 62 years (18-80 years). Twenty one percent patients had 1 comorbidity, 18 % had 2 comorbidities and 6% patients had 3 and 5 comorbidities each. Twenty four patients were on active therapy. Sixty nine percent of patients required ICU stay. Twenty five patients received plasma therapy within 7 days (early) of diagnosis of Covid-19 infection. Median day of plasma infusion from date of diagnosis of Covid-19 infection was 4 days (range: 2-25 days). Patient who had early initiation of plasma therapy had shorter duration of hospitalisation (12.7 vs 24.3 days, p = 0.000). Overall mortality in the cohort was 45.5%. There was no effect of disease status, active therapy, presence of comorbidity on mortality. There was no difference in the mortality in patients receiving early vs late initiation of plasma therapy or in patients receiving one versus two plasma therapy.

CONCLUSIONS

We provide a large series of patients with hematological malignancies and role of CPT in this group.

The 15-Months Clinical Experience of SARS-CoV-2: A Literature Review of Therapies and Adjuvants

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for the coronavirus disease of 2019 (COVID-19) that emerged in December 2019 in Wuhan, China, and rapidly spread worldwide, with a daily increase in confirmed cases and infection-related deaths. The World Health Organization declared a pandemic on the 11th of March 2020. COVID-19 presents flu-like symptoms that become severe in high-risk medically compromised subjects. The aim of this study was to perform an updated overview of the treatments and adjuvant protocols for COVID-19.

METHODS

A systematic literature search of databases was performed (MEDLINE PubMed, Google Scholar, UpToDate, Embase, and Web of Science) using the keywords: "COVID-19", "2019-nCoV", "coronavirus" and "SARS-CoV-2" (date range: 1 January 2019 to 31st October 2020), focused on clinical features and treatments.

RESULTS

The main treatments retrieved were antivirals, antimalarials, convalescent plasma, immunomodulators, corticosteroids, anticoagulants, and mesenchymal stem cells. Most of the described treatments may provide benefits to COVID-19 subjects, but no one protocol has definitively proven its efficacy.

CONCLUSIONS

While many efforts are being spent worldwide in research aimed at identifying early diagnostic methods and evidence-based effective treatments, mass vaccination is thought to be the best option against this disease in the near future.

Recent Antiviral Treatment and Vaccination Strategies Against SARS-CoV-2

Since the end of 2019, the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) has been spreading worldwide and has caused severe health and economic issues on a global scale. By the end of February 2021, more than 100 million SARS-CoV-2 cases had been reported worldwide. SARS-CoV-2 causes the coronavirus disease 2019 (COVID-19) that can be divided into three phases: An early phase with fever and cough (phase I), a pulmonary vascular disease (phase II) and a hyperinflammatory syndrome (phase III). Since viral replication plays a particularly important role in the early stage of the disease and the patient's immune system in the later course of infection, different therapeutic options arise depending on the stage of the disease. The antiviral nucleoside analogue remdesivir is the only antiviral compound with conditional approval in the European Union. Treatment with remdesivir should be initiated early (within the first seven days of symptom onset) in patients receiving supplemental oxygen without invasive ventilation. In turn, the anti-inflammatory corticosteroid dexamethasone should be administered later in the course of disease in patients receiving oxygen therapy. Since autopsies indicate an increased frequency of thromboembolic events due to COVID-19, additional treatment with anticoagulants is recommended. Since the development of novel antivirals may take years, the application of convalescent plasma from patients who recovered from a SARS-CoV-2 infection for the treatment of COVID-19 is reasonable. However, large-scale studies indicated low efficacy of convalescent plasma. Furthermore, vaccination of the population is essential to control the pandemic. Currently, the mRNA vaccine Tozinameran from BioNTech and Pfizer, the mRNA-1273 vaccine from Moderna as well as the vector vaccine AZD1222 from AstraZeneca are licensed in the European Union. All three vaccines have demonstrated high efficacy in large clinical trials. In addition to these licensed vaccines, many others are being tested in clinical trials. In the present article, an overview of therapeutic options for COVID-19 as well as vaccines for protection against SARS-CoV-2 is provided.

Evaluation by simulation of clinical trial designs for evaluation of treatment during a viral haemorrhagic fever outbreak

Background

Viral haemorrhagic fevers are characterized by irregular outbreaks with high mortality rate. Difficulties arise when implementing therapeutic trials in this context. The outbreak duration is hard to predict and can be short compared to delays of trial launch and number of subject needed (NSN) recruitment. Our objectives were to compare, using clinical trial simulation, different trial designs for experimental treatment evaluation in various outbreak scenarios.

Methods

Four type of designs were compared: fixed or group-sequential, each being single- or two-arm. The primary outcome was 14-day survival rate. For single-arm designs, results were compared to a pre-trial historical survival rate p_H. Treatments efficacy was evaluated by one-sided tests of proportion (fixed designs) and Whitehead triangular tests (group-sequential designs) with type-I-error = 0.025. Both survival rates in the control arm p_C and survival rate differences Δ (including 0) varied. Three specific cases were considered: “standard” (fixed p_C, reaching NSN for fixed designs and maximum sample size N_Max for group-sequential designs); “changing with time” (increased p_C over time); “stopping of recruitment” (epidemic ends). We calculated the proportion of simulated trials showing treatment efficacy, with K = 93,639 simulated trials to get a type-I-error PI_95% of [0.024;0.026].

Results

Under H₀ (Δ = 0), for the “standard” case, the type-I-error was maintained regardless of trial designs. For “changing with time” case, when p_C > p_H, type-I-error was inflated, and when p_C < p_H it decreased. Wrong conclusions were more often observed for single-arm designs due to an increase of Δ over time. Under H₁ (Δ = + 0.2), for the “standard” case, the power was similar between single- and two-arm designs when p_C = p_H. For “stopping of recruitment” case, single-arm performed better than two-arm designs, and fixed designs reported higher power than group-sequential designs. A web R-Shiny application was developed.

Conclusions

At an outbreak beginning, group-sequential two-arm trials should be preferred, as the infected cases number increases allowing to conduct a strong randomized control trial. Group-sequential designs allow early termination of trials in cases of harmful experimental treatment. After the epidemic peak, fixed single-arm design should be preferred, as the cases number decreases but this assumes a high level of confidence on the pre-trial historical survival rate.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01287-w.

Convalescent plasma for adults with acute COVID-19 respiratory illness (CONCOR-1): study protocol for an international, multicentre, randomized, open-label trial

BACKGROUND

Convalescent plasma has been used for numerous viral diseases including influenza, severe acute respiratory syndrome, Middle East respiratory syndrome and Ebola virus; however, evidence to support its use is weak. SARS-CoV-2 is a novel coronavirus responsible for the 2019 global pandemic of COVID-19 community acquired pneumonia. We have undertaken a randomized controlled trial to assess the efficacy and safety of COVID-19 convalescent plasma (CCP) in patients with SARS-CoV-2 infection.

METHODS

CONCOR-1 is an open-label, multicentre, randomized trial. Inclusion criteria include the following: patients > 16 years, admitted to hospital with COVID-19 infection, receiving supplemental oxygen for respiratory complications of COVID-19, and availability of blood group compatible CCP. Exclusion criteria are : onset of respiratory symptoms more than 12 days prior to randomization, intubated or imminent plan for intubation, and previous severe reactions to plasma. Consenting patients are randomized 2:1 to receive either approximately 500 mL of CCP or standard of care. CCP is collected from donors who have recovered from COVID-19 and who have detectable anti-SARS-CoV-2 antibodies quantified serologically. The primary outcome is intubation or death at day 30. Secondary outcomes include ventilator-free days, length of stay in intensive care or hospital, transfusion reactions, serious adverse events, and reduction in SARS-CoV-2 viral load. Exploratory analyses include patients who received CCP containing high titre antibodies. A sample size of 1200 patients gives 80% power to detect a 25% relative risk reduction assuming a 30% baseline risk of intubation or death at 30 days (two-sided test; α = 0.05). An interim analysis and sample size re-estimation will be done by an unblinded independent biostatistician after primary outcome data are available for 50% of the target recruitment (n = 600).

DISCUSSION

This trial will determine whether CCP will reduce intubation or death non-intubated adults with COVID-19. The trial will also provide information on the role of and thresholds for SARS-CoV-2 antibody titres and neutralization assays for donor qualification.

TRIAL REGISTRATION

Clinicaltrials.gov NCT04348656 . Registered on 16 April 2020.

Antibody Therapy: From Diphtheria to Cancer, COVID-19, and Beyond

The dawn of the 20th century saw the formative years of developments in immunology. In particular, immunochemistry, specifically pertaining to antibodies, was extensively studied. These studies laid the foundations for employing antibodies in a variety of ways. Not surprisingly, antibodies have been used for applications ranging from biomedical research to disease diagnostics and therapeutics to evaluation of immune responses during natural infection and those elicited by vaccines. Despite recent advancements in cellular immunology and the excitement of T cell therapy, use of antibodies represents a large proportion of immunotherapeutic approaches as well as clinical interventions. Polyclonal antibodies in the form of plasma or sera continue to be used to treat a number of diseases, including autoimmune disorders, cancers, and infectious diseases. Historically, antisera to toxins have been the longest serving biotherapeutics. In addition, intravenous immunoglobulins (IVIg) have been extensively used to treat not only immunodeficiency conditions but also autoimmune disorders. Beyond the simplistic suppositions of their action, the IVIg have also unraveled the immune regulatory and homeostatic ramifications of their use. The advent of monoclonal antibodies (MAbs), on the other hand, has provided a clear pathway for their development as drug molecules. MAbs have found a clear place in the treatment of cancers and extending lives and have been used in a variety of other conditions. In this review, we capture the important developments in the therapeutic applications of antibodies to alleviate disease, with a focus on some of the recent developments.

Effectiveness of convalescent plasma in Indian patients with COVID-19

BACKGROUND

Convalescent plasma (CP) is being used as a treatment option in hospitalized patients with COVID-19. Till date, there is conflicting evidence on efficacy of CP in reducing COVID-19 related mortality.

OBJECTIVE

To evaluate the effect of CP on 28-day mortality reduction in patients with COVID-19.

METHODS

We did a multi-centre, retrospective case control observational study from 1st May 2020 to 31st August 2020. A total of 1079 adult patients with moderate and severe COVID-19 requiring oxygen, were reviewed. Of these, 694 patients were admitted to ICU. Out of these, 333 were given CP along with best supportive care and remaining 361 received best supportive care only.

RESULTS

In the overall group of 1079 patients, mortality in plasma vs no plasma group was statistically not significant (22.4% vs 18.5%; p = 0.125; OR = 1.27, 95% CI: 0.94--1.72). However, in patients with COVID-19 admitted to ICU, mortality was significantly lower in plasma group (25.5% vs 33.2%; p = 0.026; OR = 0.69, 95%CI: 0.50-0.96). This benefit of reduced mortality was most seen in age group 60 to 74 years (26.7% vs 43.0%; p = 0.004; OR = 0.48, 95% CI: 0.29-0.80), driven mostly by females of this age group (23.1% vs 53.5%; p = 0.013; OR = 0.26, 95% CI: 0.09-0.78). Significant difference in mortality was observed in patients with one comorbidity (22.3% vs 36.5%; p = 0.004; OR = 0.50, 95% CI: 0.31-0.80). Moreover, patients on ventilator had significantly lower mortality in the plasma arm (37.2% vs 49.3%; p = 0.009; OR = 0.61, 95% CI: 0.42-0.89); particularly so for patients on invasive mechanical ventilation (63.9% vs 82.9%; p = 0.014; OR = 0.37, 95% CI: 0.16-0.83).

CONCLUSION

The use of CP was associated with reduced mortality in COVID-19 elderly patients admitted in ICU, above 60 years of age, particularly females, those with comorbidities and especially those who required some form of ventilation.

Reviewing the Ethical Concerns of the Convalescent Plasma Therapy in COVID-19

The understanding of coronavirus disease 2019 (COVID-19) is evolving periodically. There is also a marked increase in COVID-19 patients’ demand for the provision of COVID-19 convalescent plasma (CCP) therapy. With the review of the literature, the stage of speculation is quickly moving towards conformity, with the interim guidelines given by the Food and Drug Administration (FDA) in the United States, United Kingdom’s blood transfusion services, Saudi’s FDA, and the Indian Council for Medical Research, in addition to the European health authorities. It is prudent to address the ethical concerns that merit consideration while harvesting and utilizing CCP as a therapeutic tool in local hospital setting.

Targeting Ebola virus replication through pharmaceutical intervention

Introduction. The consistent emergence/reemergence of filoviruses into a world that previously lacked an approved pharmaceutical intervention parallels an experience repeatedly played-out for most other emerging pathogenic zoonotic viruses. Investment to preemptively develop effective and low-cost prophylactic and therapeutic interventions against viruses that have high potential for emergence and societal impact should be a priority.Areas covered. Candidate drugs can be characterized into those that interfere with cellular processes required for Ebola virus (EBOV) replication (host-directed), and those that directly target virally encoded functions (direct-acting). We discuss strategies to identify pharmaceutical interventions for EBOV infections. PubMed/Web of Science databases were searched to establish a detailed catalog of these interventions.Expert opinion. Many drug candidates show promising in vitro inhibitory activity, but experience with EBOV shows the general lack of translation to in vivo efficacy for host-directed repurposed drugs. Better translation is seen for direct-acting antivirals, in particular monoclonal antibodies. The FDA-approved monoclonal antibody treatment, Inmazeb™ is a success story that could be improved in terms of impact on EBOV-associated disease and mortality, possibly by combination with other direct-acting agents targeting distinct aspects of the viral replication cycle. Costs need to be addressed given EBOV emergence primarily in under-resourced countries.