Design and analysis considerations in the Ebola_Tx trial evaluating convalescent plasma in the treatment of Ebola virus disease in Guinea during the 2014-2015 outbreak

HemoClear: A Practical and Cost-Effective Alternative to Conventional Convalescent Plasma Retrieval Methods

Convalescent plasma has increasingly been used to treat various viral infections and confer post-exposure prophylactic protection during the last decade and has demonstrated favorable clinical outcomes in patients infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) during the recent COVID-19 pandemic. The pandemic has highlighted the need for cost-effective, accessible, and easy-to-use alternatives to conventional blood plasmapheresis techniques, allowing hospitals to become more self-sufficient in harvesting and transfusing donor plasma into recipients in a single setting. To this end, the use of a membrane-based bedside plasmapheresis device (HemoClear) was evaluated in an open-label, non-randomized prospective trial in Suriname in 2021, demonstrating its practicality and efficacy in a low-to middle-income country. This paper will review the use of this method and its potential to expedite the process of obtaining convalescent plasma, especially during pandemics and in resource-constrained settings.

Correlation between mortality and blood transfusion in patients with major surgery initially admitted to intensive care unit: a retrospective analysis

PURPOSE

Transfusing red blood cells promptly corrects anemia and improves tissue oxygenation in around 40% of patients hospitalized in the intensive care unit (ICU) after major surgical operations. This study's goal is to investigate how blood transfusions affect the mortality rates of patients after major surgery who are hospitalized in the ICU.

METHODS

Retrospective research was done on recently hospitalized patients who had major procedures in the ICU between October 2020 and February 2022 at the Huanggang Central Hospital of Yangtze University, China. The patients' prognoses at three months were used to classify them as either survivors or deceased. Patient demographic information, laboratory results, and blood transfusion histories were acquired, and the outcomes of the two groups were compared based on the differences. Univariate and multivariate logistic regression analyses were used to examine the prognosis of surgical disease patients first admitted to the ICU. The receiver operating characteristic (ROC) curve was used to evaluate the predictive power of each risk factor. The relationship between transfusion frequency, transfusion modality, and patient outcome was examined using Spearman's correlation analysis.

RESULTS

Data from 384 patients was included in the research; of them, 214 (or 55.7%) died within three months of their first stay in the ICU. The death group had higher scores on the Acute Physiology and Chronic Health Evaluation II (APACHE II) and the Sequential Organ Failure Assessment (SOFA) than the survival group did (all P < 0.05); the death group also had lower scores on the Glasgow Coma Scale, systolic blood pressure, hemoglobin, platelet distribution width, and blood transfusion ratio. Multivariate logistic regression analysis revealed an odds ratio (OR) of 1.654 (1.281-1.989), a 95% confidence interval (CI) of 1.440 (1.207-1.701), and a P value of 0.05 for death in patients undergoing major surgery who were hospitalized to the intensive care unit (ICU). Areas under the ROC curve (AUC) of 0.836, 0.799, and 0.871, respectively, and 95% CIs of 0.796-0.875, 0.755-0.842, and 0.837-0.904, respectively, all P0.05, had significant predictive value for patients initially admitted to the ICU and for APACHE II score > = 12 points, SOFA score > = 6, and blood transfusion. When all three indicators were used jointly to predict a patient's prognosis after major surgery, the accuracy increased to 86.4% (sensitivity) and 100% (specificity). There was a negative correlation between the number of blood transfusions a patient had and their outcome (r = 0.605, P < 0.001) and death (r = 0.698, P < 0.001).

CONCLUSION

A higher initial ICU APACHE II score, SOFA score, and a number of blood transfusions were associated with improved survival for patients undergoing major surgical operations. Patients' death rates have increased with the increase in the frequency and variety of blood transfusions.

The transmembrane replacement H7N9-VLP vaccine displays high levels of protection in mice

The incidence of infections caused by the H7N9 subtype of the influenza virus has expanded rapidly in China in recent decades, generating massive economic loss and posing a significant threat to public health. In the absence of specialized antiviral treatments or long-term effective preventative vaccinations, it is critical to constantly enhance vaccines and create effective antiviral drugs to prevent the recurrence of pandemics. In the present study, a transmembrane-substituted (TM) virus-like particle (VLP)-based vaccine was created by replacing the transmembrane region of hemagglutinin (HA) protein with the transmembrane region of the H3 HA protein and then used to immunize BALB/c mice. Sera and T cells were collected from the immunized mice to evaluate the passive immune effects. Our results showed that naïve mice achieved 80–100% protection against homologous and heterologous H7N9 influenza strains after receiving passive serum immunization; the protective effect of the TM VLPs was more evident than that of the wild-type HA VLPs. In contrast, mice immunized with passive T cells achieved only 20 to 80% protection against homologous or heterologous strains. Our findings significantly contribute to understanding the control of the H7N9 virus and the development of a vaccine.

Novel protocol for selection of SARS-CoV2 convalenscent plasma donors

Background/Aim. Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) 2019 infection represents a global problem. At this moment, in October 2020, there is no vaccine or efficient treatment for infected patients. Treatment with blood plasma rich with anti-SARS-CoV-2 specific antibodies might be a safe, and effective therapy for COVID-19 patients. Methods. A total of 768 patients were analyzed in this study, whose samples were collected in a time interval from May 1, 2020, till August 15, 2020. Patients were enrolled in the study from COVID-19 hospitals and out-clinics. In-house ELISA tests were developed to measure the concentration of anti-S1S2 spike and anti-nucleoprotein (np) (IgG, IgA, IgM) SARS-CoV-2 antibodies. Blood convalescent plasma was selectively collected from recovered patients according to specific antibodies concentration. Results. The highest concentrations of anti-S1S2 spike or anti-np specific IgG antibodies were detected in patients with the moderate/heavy clinical form of the infection. An extremely high concentration of anti-S1S2 spike IgG and anti-np IgG was demonstrated in 3% and 6% of patients who recovered from severe COVID-19, respectively. Of tested hospitalized patients, 63% and 51% had modest levels of anti-S1S2 spike and anti-np, respectively. After 60 days, in our selected donors, concentrations of anti- S1S2 spike IgG and anti-np IgG antibodies increased in 67% and 58% of donors, respectively. Conclusion. In-house developed ELISA tests enable a novel protocol for selecting convalescent blood plasma donors recovered from SARS-CoV-2 infection.

Passive immunization and its rebirth in the era of the COVID-19 pandemic

The COVID-19 pandemic, caused by SARS-CoV-2, has led to a rapid search for therapeutic and preventive measures because of the potentially severe course of infection. The antiviral drug, remdesivir, and the anti-inflammatory agent, dexamethasone, have shown beneficial effects. As the current COVID-19 vaccines are not yet fully available to everyone, or they may not be readily and universally accepted, various treatment options are being evaluated and will still be needed under these conditions. One of these treatment options, passive immunization, has shown promise in some studies. Further research is needed to determine the utility of immunotherapy with convalescent plasma or artificially produced monoclonal antibodies for the treatment of symptomatic patients, and potentially for use as post-exposure prophylaxis, at least until more effective drugs are available or safe and effective vaccines are distributed and administered to everyone.

Clinical use of Convalescent Plasma in the COVID-19 pandemic: a transfusion-focussed gap analysis with recommendations for future research priorities

BACKGROUND AND OBJECTIVES

Use of convalescent plasma for coronavirus disease 2019 (COVID-19) treatment has gained interest worldwide. However, there is lack of evidence on its dosing, safety and effectiveness. Until data from clinical studies are available to provide solid evidence for worldwide applicable guidelines, there is a need to provide guidance to the transfusion community and researchers on this emergent therapeutic option. This paper aims to identify existing key gaps in current knowledge in the clinical application of COVID-19 convalescent plasma (CCP).

MATERIALS AND METHODS

The International Society of Blood Transfusion (ISBT) initiated a multidisciplinary working group with worldwide representation from all six continents with the aim of reviewing existing practices on CCP use from donor, product and patient perspectives. A subgroup of clinical transfusion professionals was formed to draft a document for CCP clinical application to identify the gaps in knowledge in existing literature.

RESULTS

Gaps in knowledge were identified in the following main domains: study design, patient eligibility, CCP dose, frequency and timing of CCP administration, parameters to assess response to CCP treatment and long-term outcome, adverse events and CCP application in less-resourced countries as well as in paediatrics and neonates.

CONCLUSION

This paper outlines a framework of gaps in the knowledge of clinical deployment of CPP that were identified as being most relevant. Studies to address the identified gaps are required to provide better evidence on the effectiveness and safety of CCP use.

Ebola virus disease: An emerging and re-emerging viral threat

The genus Ebolavirus from the family Filoviridae is composed of five species including Sudan ebolavirus, Reston ebolavirus, Bundibugyo ebolavirus, Taï Forest ebolavirus, and Ebola virus (previously known as Zaire ebolavirus). These viruses have a large non-segmented, negative-strand RNA of approximately 19 kb that encodes for glycoproteins (i.e., GP, sGP, ssGP), nucleoproteins, virion proteins (i.e., VP 24, 30,40) and an RNA dependent RNA polymerase. These viruses have become a global health concern because of mortality, their rapid dissemination, new outbreaks in West-Africa, and the emergence of a new condition known as "Post-Ebola virus disease syndrome" that resembles inflammatory and autoimmune conditions such as rheumatoid arthritis, systemic lupus erythematosus and spondyloarthritis with uveitis. However, there are many gaps in the understanding of the mechanisms that may induce the development of such autoimmune-like syndromes. Some of these mechanisms may include a high formation of neutrophil extracellular traps, an uncontrolled "cytokine storm", and the possible formation of auto-antibodies. The likely appearance of autoimmune phenomena in Ebola survivors suppose a new challenge in the management and control of this disease and opens a new field of research in a special subgroup of patients. Herein, the molecular biology, pathogenesis, clinical manifestations, and treatment of Ebola virus disease are reviewed and some strategies for control of disease are discussed.

Towards quantification of protective antibody responses by passive transfer of the 1st WHO International Standard for Ebola virus antibody in a guinea pig model

Ebola virus (EBOV) represents a major concern to global health due to the unpredictable nature of outbreaks. Infection with EBOV can cause a severe viral haemorrhagic fever with no licensed vaccine or treatment, restricting work with live EBOV to Containment/Biosafety Level 4 facilities. Whilst the magnitude of recent outbreaks has provided an impetus for vaccine and antiviral development, establishing the efficacy of candidate vaccine materials relies on EBOV challenge models and advanced human trials should outbreaks occur and where logistics and funding allow. To address these hurdles in vaccine development, we investigated whether a recently established serological reference standard, the 1st WHO International Standard for Ebola virus antibody, could be used to provide a quantifiable correlate of immune protection in vivo. Dilutions of the International Standard were inoculated into naïve guinea pigs 24 h before challenge with a lethal dose of Ebola virus. Only subjects receiving the highest dose of the International Standard exhibited evidence of delayed progression. Due to it being a WHO established reagent and available globally upon request, this standard allows for effective comparisons of data between laboratories and may prove valuable to select the candidate vaccines that are most likely to confer humoral immune protection ensuring the most promising candidates progress into efficacy studies.

Human Polyclonal Antibodies Produced by Transchromosomal Cattle Provide Partial Protection Against Lethal Zaire Ebolavirus Challenge in Rhesus Macaques

Antibody therapy has been used to treat a variety of diseases and the success of ZMapp and other monoclonal antibody-based therapies during the 2014-2016 West African Ebola outbreak has shown this countermeasure can be a successful therapy for Ebola hemorrhagic fever. This study utilized transchromosomal bovines (TcB) vaccinated with a DNA plasmid encoding Ebola virus glycoprotein sequence to produce human polyclonal antibodies directed against Ebola virus glycoprotein. When administered 1 day postinfection, these TcB polyclonal antibodies provided partial protection and resulted in a 50% survival rate following a lethal challenge of Ebola virus Makona in rhesus macaques.

The Special Pathogens Research Network: Enabling Research Readiness

The 2013-2016 epidemic of Ebola virus disease (EVD) that originated in West Africa underscored many of the challenges to conducting clinical research during an ongoing infectious disease epidemic, both in the most affected countries of Guinea, Liberia, and Sierra Leone, as well as in the United States and Europe, where a total of 27 patients with EVD received care in biocontainment units. The Special Pathogens Research Network (SPRN) was established in the United States in November 2016 to provide an organizational structure to leverage the expertise of the 10 Regional Ebola and Other Special Pathogen Treatment Centers (RESPTCs); it was intended to develop and support infrastructure to improve readiness to conduct clinical research in the United States. The network enables the rapid activation and coordination of clinical research in the event of an epidemic and facilitates opportunities for multicenter research when the RESPTCs are actively caring for patients requiring a biocontainment unit. Here we provide an overview of opportunities identified in the clinical research infrastructure during the West Africa EVD epidemic and the SPRN activities to meet the ongoing challenges in the context of Ebola virus and other special pathogens.

What motivates Ebola survivors to donate plasma during an emergency clinical trial? The case of Ebola-Tx in Guinea

INTRODUCTION

During the 2014 Ebola Virus Disease (EVD) epidemic, the Ebola-Tx trial evaluated the use of convalescent plasma (CP) in Guinea. The effectiveness of plasmapheresis trials depends on the recruitment of plasma donors. This paper describes what motivated or deterred EVD survivors to donate CP, providing insights for future plasmapheresis trials and epidemic preparedness.

METHODS

This qualitative study, part of Ebola-Tx, researched and addressed emergent trial difficulties through interviewing, participant observation and focus group discussions. Sampling was theoretical and retroductive analysis was done in NVivo 10.

RESULTS

Willingness or hesitance to participate in plasma donation depended on factors at the interface of pre-existing social dynamics; the impact of the disease and the consequent emergency response including the trial set-up. For volunteers, motivation to donate was mainly related to the feeling of social responsibility inspired by having survived EVD and to positive perceptions of plasmapheresis technology despite still unknown trial outcomes. Conversely, confidentiality concerns when volunteering due to stigmatization of survivors and perceived decrease in vital strength and in antibodies when donating, leading to fears of loss in protection against EVD, were main deterrents. The dynamic (dis)trust in Ebola Response Actors and in other survivors further determined willingness to participate and lead to the emergence/decline of rumours related to blood stealing and treatment effectiveness. Historic inter-ethnic relations in the health care setting further defined volunteering along socio-economic and ethnic lines. Finally, lack of follow-up and of dedicated care further impacted on motivation to volunteer.

CONCLUSIONS

Ebola-Tx was the first trial to solicit and evaluate blood-product donation as an experimental treatment on a large scale in Sub-Saharan Africa. An effective donation system requires directly engaging with emergent social barriers and providing an effective ethical response, including improved and transparent communication, effective follow-up after donation, assuring confidentiality and determining ethical incentives.

Performance of different clinical trial designs to evaluate treatments during an epidemic

In the 2013-2016 west Africa outbreak of Ebola Virus Disease (EVD), most of the planned clinical trials failed to reach a conclusion within the time frame of the epidemic. The performance of clinical trial designs for the evaluation of one or more experimental treatments in the specific context of an ongoing epidemic with changing case fatality rates (CFR) and unpredictable case numbers is unclear. We conduct a comprehensive evaluation of commonly used two- and multi-arm clinical trial designs based on real data, which was recorded during the 2013-16 EVD epidemic in west Africa. The primary endpoint is death within 14 days of hospitalization. The impact of the recruitment start times relative to the time course of the epidemic on the operating characteristics of the clinical trials is analysed. Designs with frequent interim analyses with the possibility of early stopping are shown to outperform designs with only a single analysis not only in terms of average time to conclusion and average sample size, but also in terms of the probability of reaching any conclusion at all. Historic control designs almost always result in substantially inflated false positive rates, when the case fatality rate changes over time. Response-adaptive randomization may be a compromise between the goal of scientific validity and the ethical goal of minimizing the number of patients allocated to ineffective treatments.

Protected to death: systematic exclusion of pregnant women from Ebola virus disease trials

BACKGROUND

For 30 years, women have sought equal opportunity to be included in trials so that drugs are equitably studied in women as well as men; regulatory guidelines have changed accordingly. Pregnant women, however, continue to be excluded from trials for non-obstetric conditions, though they have been included for trials of life-threatening diseases because prospects for maternal survival outweighed potential fetal risks. Ebola virus disease is a life-threatening infection without approved treatments or vaccines. Previous Ebola virus (EBOV) outbreak data showed 89-93% maternal and 100% fetal/neonatal mortality. Early in the 2013-2016 EBOV epidemic, an expert panel pointed to these high mortality rates and the need to prioritize and preferentially allocate unregistered interventions in favor of pregnant women (and children). Despite these recommendations and multiple ethics committee requests for their inclusion on grounds of justice, equity, and medical need, pregnant women were excluded from all drug and vaccine trials in the affected countries, either without justification or on grounds of potential fetal harm. An opportunity to offer pregnant women the same access to potentially life-saving interventions as others, and to obtain data to inform their future use, was lost. Once again, pregnant women were denied autonomy and their right to decide.

CONCLUSION

We recommend that, without clear justification for exclusion, pregnant women are included in clinical trials for EBOV and other life-threatening conditions, with lay language on risks and benefits in information documents, so that pregnant women can make their own decision to participate. Their automatic exclusion from trials for other conditions should be questioned.

Generation and characterization of protective antibodies to Marburg virus

Marburg virus (MARV) and Ebola virus (EBOV) have been a source of epidemics and outbreaks for several decades. We present here the generation and characterization of the first protective antibodies specific for wild-type MARV. Non-human primates (NHP), cynomolgus macaques, were immunized with viral-replicon particles expressing the glycoproteins (GP) of MARV (Ci67 isolate). An antibody fragment (single-chain variable fragment, scFv) phage display library was built after four immunogen injections, and screened against the GP_1-649 of MARV. Sequencing of 192 selected clones identified 18 clones with distinct V_H and V_L sequences. Four of these recombinant antibodies (R4A1, R4B11, R4G2, and R3F6) were produced in the scFv-Fc format for in vivo studies. Mice that were challenged with wild-type Marburg virus (Ci67 isolate) receiving 100 µg of scFv-Fc on days -1, 1 and 3 demonstrated protective efficacies ranging from 75-100%. The amino-acid sequences of the scFv-Fcs are similar to those of their human germline counterparts, sharing an identity ranging between 68 and 100% to human germline immunoglobulin. These results demonstrate for the first time that recombinant antibodies offer protection against wild-type MARV, and suggest they may be promising candidates for further therapeutic development especially due to their human homology.

Use of convalescent plasma in Ebola virus infection

The recent Ebola virus epidemics which threatened three West African countries (Dec.2014-Apr.2016) has urged global collaborative health organizations and countries to set up measures to stop the infection and to treat patients, near half of them being at risk of death. Convalescent plasma-recovered from rescued West Africans-was considered a feasible therapeutic option. Efficacy was difficult to evaluate because of numerous unknowns (especially evolution of neutralizing antibodies), prior to the cessation of active transmission. This raises a large body of questions spanning epidemiological, virological, immunological but also ethical, sociological and anthropological aspects, alongside with public health concerns, in order to be better prepared to the next outbreak. This essay summarizes efforts made by a large number of groups worldwide, and attempts to address still unanswered questions on the benefit of specific versus non-specific plasma on altered-leaking-vascular endothelia in Ebola infection.

Passive Immunotherapy: Assessment of Convalescent Serum Against Ebola Virus Makona Infection in Nonhuman Primates

Background. Convalescent serum and blood were used to treat patients during outbreaks of Zaire ebolavirus (ZEBOV) infection in 1976 and 1995, with inconclusive results. During the recent 2013–2016 West African epidemic, serum/plasma from survivors of ZEBOV infection was used to treat patients in the affected countries and several repatriated patients. The effectiveness of this strategy remains unknown.

Methods. Nine rhesus monkeys were experimentally infected with ZEBOV-Makona. Beginning on day 3 after exposure (at the onset of viremia), 4 animals were treated with homologous ZEBOV-Makona convalescent macaque sera, 3 animals were treated in parallel with heterologous Sudan ebolavirus (SEBOV) convalescent macaque sera, and 2 animals served as positive controls and were not treated. Surviving animals received additional treatments on days 6 and 9.

Results. Both untreated control animals died on postinfection day 9. All 4 ZEBOV-Makona–infected macaques treated with homologous ZEBOV-Makona convalescent sera died on days 8–9. One macaque treated with heterologous SEBOV convalescent sera survived, while the other animals treated with the heterologous SEBOV sera died on days 7 and 9.

Conclusions. The findings suggest that convalescent sera alone is not sufficient for providing 100% protection against lethal ZEBOV infection when administered at the onset of viremia.