Early safety indicators of COVID-19 convalescent plasma in 5000 patients

Reconstituted Extracellular Vesicles from Human Platelets Decrease Viral Myocarditis in Mice

Patients with viral myocarditis are at risk of sudden death and may progress to dilated cardiomyopathy (DCM). Currently, no disease-specific therapies exist to treat viral myocarditis. Here it is examined whether reconstituted, lyophilized extracellular vesicles (EVs) from platelets from healthy men and women reduce acute or chronic myocarditis in male mice. Human-platelet-derived EVs (PEV) do not cause toxicity, damage, or inflammation in naïve mice. PEV administered during the innate immune response significantly reduces myocarditis with fewer epidermal growth factor (EGF)-like module-containing mucin-like hormone receptor-like 1 (F4/80) macrophages, T cells (cluster of differentiation molecules 4 and 8, CD4 and CD8), and mast cells, and improved cardiac function. Innate immune mediators known to increase myocarditis are decreased by innate PEV treatment including Toll-like receptor (TLR)4 and complement. PEV also significantly reduces perivascular fibrosis and remodeling including interleukin 1 beta (IL-1β), transforming growth factor-beta 1, matrix metalloproteinase, collagen genes, and mast cell degranulation. PEV given at days 7-9 after infection reduces myocarditis and improves cardiac function. MicroRNA (miR) sequencing reveals that PEV contains miRs that decrease viral replication, TLR4 signaling, and T-cell activation. These data show that EVs from the platelets of healthy individuals can significantly reduce myocarditis and improve cardiac function.

Raman Fingerprints of SARS-CoV-2 Omicron Subvariants: Molecular Roots of Virological Characteristics and Evolutionary Directions

The latest RNA genomic mutation of SARS-CoV-2 virus, termed the Omicron variant, has generated a stream of highly contagious and antibody-resistant strains, which in turn led to classifying Omicron as a variant of concern. We systematically collected Raman spectra from six Omicron subvariants available in Japan (i.e., BA.1.18, BA.2, BA.4, BA.5, XE, and BA.2.75) and applied machine-learning algorithms to decrypt their structural characteristics at the molecular scale. Unique Raman fingerprints of sulfur-containing amino acid rotamers, RNA purines and pyrimidines, tyrosine phenol ring configurations, and secondary protein structures clearly differentiated the six Omicron subvariants. These spectral characteristics, which were linked to infectiousness, transmissibility, and propensity for immune evasion, revealed evolutionary motifs to be compared with the outputs of genomic studies. The availability of a Raman "metabolomic snapshot", which was then translated into a barcode to enable a prompt subvariant identification, opened the way to rationalize in real-time SARS-CoV-2 activity and variability. As a proof of concept, we applied the Raman barcode procedure to a nasal swab sample retrieved from a SARS-CoV-2 patient and identified its Omicron subvariant by coupling a commercially available magnetic bead technology with our newly developed Raman analyses.

The VA Research Enterprise: A Platform for National Partnerships Toward Evidence Building and Scientific Innovation

Background

Within a year of the start of the COVID-19 pandemic, the US Department of Veterans Affairs (VA) was managing about 300 COVID-19-related research projects across roughly 100 facilities, which has since grown to more than 900 projects. This robust set of activities arose from an existing enterprise strategy and aimed at identifying needs for supporting the clinical care mission, more rapidly leveraging resources, and coordinating research across the VA. The VA's efforts to implement an enterprise strategy before March 2020 positioned its research community to dynamically partner with other federal agencies, academic institutions, and industry in addressing a national public health emergency.

Observations

The VA research enterprise involves a broad range of functions, scientific and clinical leaders, and organizational resources to enhance the health and care of veterans and the nation. The scope of research activities enables it to support its priorities while also partnering with others who share in mutual commitments to veteran health. Moving toward being the nation's learning health care system, the VA's leadership support, staff, patient volunteers, and partners were key contributors to a national response to COVID-19. Swift action and consistent communication helped address the complexities of the pandemic and strengthened the VA's ability to prepare and mobilize for emergencies and other potential disease outbreaks. Documenting strategies and practices can enhance future opportunities aimed at addressing the most challenging health care needs while also focusing on the primary mission to serve veterans.

Conclusions

The COVID-19 pandemic contributed to critical knowledge and lessons that enabled the VA to advance enterprise goals, particularly in the context of its health care system. Sharing these unique processes and experiences will inform current and future partnerships among research, clinical, and public health communities oriented to serve veterans and the nation through scientific innovation.

[Efficacy and safety of convalescent plasma administration in patients with COVID-19 infection]

INTRODUCTION

During the COVID-19 pandemic, several strategies were suggested for the management of the disease, including pharmacological and non-pharmacological treatments such as convalescent plasma (CP). The use of CP was suggested due to the beneficial results shown in treating other viral diseases.

OBJECTIVE

To determine the efficacy and safety of CP obtained from whole blood in patients with COVID-19.

METHODS

Pilot clinical trial in patients with COVID-19 from a general hospital. The subjects were separated into three groups that received the transfusion of 400ml of CP (n=23) or 400ml of standard plasma (SP) (n=19) and a non-transfused group (NT) (n=37). Patients also received the standard available medical treatment for COVID-19. Subjects were followed up daily from admission to day 21.

RESULTS

The CP did not improve the survival curve in moderate and severe variants of COVID-19, nor did it reduce the degree of severity of the disease evaluated with the COVID-19 WHO and SOFA clinical progression scale. No patient had a severe post-transfusion reaction to CP.

CONCLUSIONS

Treatment with CP does not reduce the mortality of patients even when its administration has a high degree of safety.

Navigating the Post-COVID-19 Immunological Era: Understanding Long COVID-19 and Immune Response

The COVID-19 pandemic has affected the world unprecedentedly, with both positive and negative impacts. COVID-19 significantly impacted the immune system, and understanding the immunological consequences of COVID-19 is essential for developing effective treatment strategies. The purpose of this review is to comprehensively explore and provide insights into the immunological aspects of long COVID-19, a phenomenon where individuals continue to experience a range of symptoms and complications, even after the acute phase of COVID-19 infection has subsided. The immune system responds to the initial infection by producing various immune cells and molecules, including antibodies, T cells, and cytokines. However, in some patients, this immune response becomes dysregulated, leading to chronic inflammation and persistent symptoms. Long COVID-19 encompasses diverse persistent symptoms affecting multiple organ systems, including the respiratory, cardiovascular, neurological, and gastrointestinal systems. In the post-COVID-19 immunological era, long COVID-19 and its impact on immune response have become a significant concern. Post-COVID-19 immune pathology, including autoimmunity and immune-mediated disorders, has also been reported in some patients. This review provides an overview of the current understanding of long COVID-19, its relationship to immunological responses, and the impact of post-COVID-19 immune pathology on patient outcomes. Additionally, the review addresses the current and potential treatments for long COVID-19, including immunomodulatory therapies, rehabilitation programs, and mental health support, all of which aim to improve the quality of life for individuals with long COVID-19. Understanding the complex interplay between the immune system and long COVID-19 is crucial for developing targeted therapeutic strategies and providing optimal care in the post-COVID-19 era.

Impact of the COVID-19 pandemic on blood donation and transfusions in the United States in 2020

INTRODUCTION

Reports have suggested the COVID-19 pandemic resulted in blood donation shortages and adverse impacts on the blood supply. Using data from the National Blood Collection and Utilization Survey (NBCUS), we quantified the pandemic's impact on red blood cell (RBC) and apheresis platelet collections and transfusions in the United States during year 2020.

METHODS

The 2021 NBCUS survey instrument was modified to include certain blood collection and utilization variables for 2020. The survey was distributed to all US blood collection centers, all US hospitals performing ≥1000 surgeries annually, and a 40% random sample of hospitals performing 100-999 surgeries annually. Weighting and imputation were used to generate national estimates for whole blood and apheresis platelet donation; RBC and platelet transfusion; and convalescent plasma distribution.

RESULTS

Whole blood collections were stable from 2019 (9,790,000 units; 95% CI: 9,320,000-10,261,000) to 2020 (9,738,000 units; 95% CI: 9,365,000-10,110,000). RBC transfusions decreased by 6.0%, from 10,852,000 units (95% CI: 10,444,000-11,259,000) in 2019 to 10,202,000 units (95% CI: 9,811,000-10,593,000) in 2020. Declines were steepest during March-April 2020, with transfusions subsequently rebounding. Apheresis platelet collections increased from 2,359,000 units (95% CI: 2,240,000-2,477,000) in 2019 to 2,408,000 units (95% CI: 2,288,000-2,528,000) in 2020. Apheresis platelet transfusions increased from 1,996,000 units (95% CI: 1,846,000-2,147,000) in 2019 to 2,057,000 units (95% CI: 1,902,000-2,211,000) in 2020.

CONCLUSION

The COVID-19 pandemic resulted in reduced blood donations and transfusions in some months during 2020 but only a minimal annualized decline compared with 2019.

Exercise and Experiments of Nature

In this article, we highlight the contributions of passive experiments that address important exercise-related questions in integrative physiology and medicine. Passive experiments differ from active experiments in that passive experiments involve limited or no active intervention to generate observations and test hypotheses. Experiments of nature and natural experiments are two types of passive experiments. Experiments of nature include research participants with rare genetic or acquired conditions that facilitate exploration of specific physiological mechanisms. In this way, experiments of nature are parallel to classical "knockout" animal models among human research participants. Natural experiments are gleaned from data sets that allow population-based questions to be addressed. An advantage of both types of passive experiments is that more extreme and/or prolonged exposures to physiological and behavioral stimuli are possible in humans. In this article, we discuss a number of key passive experiments that have generated foundational medical knowledge or mechanistic physiological insights related to exercise. Both natural experiments and experiments of nature will be essential to generate and test hypotheses about the limits of human adaptability to stressors like exercise. © 2023 American Physiological Society. Compr Physiol 13:4879-4907, 2023.

The evolving regulatory landscape in regenerative medicine

Regenerative medicine as a field has emerged as a new component of modern medicine and medical research that encompasses a wide range of products including cellular and acellular therapies. As this new field emerged, regulatory agencies like the Food and Drug Administration (FDA) rapidly adapted existing regulatory frameworks to address the transplantation, gene therapy, cell-based therapeutics, and acellular biologics that fall under the broader regenerative medicine umbrella. Where it has not been possible to modify existing regulation and processes, entirely new frameworks have been generated with the intention of providing flexible, forward-facing systems to regulate this rapidly growing field. This review discusses the current state of FDA regulatory affairs in the context of stem cells and extracellular vesicles by highlighting gaps in the current regulatory system and then discussing where regulatory science in regenerative medicine may be headed based on these gaps and the FDA's historical ability to deal with emerging fields. Lastly, we utilize case studies in stem cell and acellular based treatments to demonstrate how regulatory science has evolved in regenerative medicine and highlight the ongoing clinical efforts and challenges of these therapies.

Alpha-1-antitrypsin and its variant-dependent role in COVID-19 pathogenesis

Rationale

SARS-CoV-2 entry into host cells is facilitated by endogenous and exogenous proteases that proteolytically activate the spike glycoprotein and antiproteases inhibiting this process. Understanding the key actors in viral entry is crucial for advancing knowledge of virus tropism, pathogenesis, and potential therapeutic targets.

Objectives

We aimed to investigate the role of naïve serum and alpha-1-antitrypsin (AAT) in inhibiting protease-mediated SARS-CoV-2 entry and explore the implications of AAT deficiency on susceptibility to different SARS-CoV-2 variants.

Findings

Our study demonstrates that naïve serum exhibits significant inhibition of SARS-CoV-2 entry, with AAT identified as the major serum protease inhibitor potently restricting entry. Using pseudoparticles, replication-competent pseudoviruses, and authentic SARS-CoV-2, we show that AAT inhibition occurs at low concentrations compared with those in serum and bronchoalveolar tissues, suggesting physiological relevance. Furthermore, sera from subjects with an AAT-deficient genotype show reduced ability to inhibit entry of both Wuhan-Hu-1 (WT) and B.1.617.2 (Delta) but exhibit no difference in inhibiting B.1.1.529 (Omicron) entry.

Conclusions

AAT may have a variant-dependent therapeutic potential against SARS-CoV-2. Our findings highlight the importance of further investigating the complex interplay between proteases, antiproteases, and spike glycoprotein activation in SARS-CoV-2 and other respiratory viruses to identify potential therapeutic targets and improve understanding of disease pathogenesis.

Convalescent plasma therapy in COVID-19: Unravelling the data using the principles of antibody therapy

INTRODUCTION

When the COVID-19 pandemic struck no specific therapies were available and many turned to COVID-19 convalescent plasma (CCP), a form of antibody therapy. The literature provides mixed evidence for CCP efficacy.

AREAS COVERED

PubMed was searched using the words COVID-19 and convalescent plasma and individual study designs were evaluated for adherence to the three principles of antibody therapy, i.e. that plasma 1) contain specific antibody; 2) have enough specific antibody to mediate a biological effect; and 3) be administered early in the course of disease. Using this approach, a diverse and seemingly contradictory collection of clinical findings was distilled into a consistent picture whereby CCP was effective when used according to the above principles of antibody therapy. In addition, CCP therapy in immunocompromised patients is useful at any time in the course of disease.

EXPERT OPINION

CCP is safe and effective when used appropriately. Today, most of humanity has some immunity to SARS-CoV-2 from vaccines and infection, which has lessened the need for CCP in the general population. However, COVID-19 in immunocompromised patients is a major therapeutic challenge, and with the deauthorization of all SARS-CoV-2-spike protein-directed monoclonal antibodies, CCP is the only antibody therapy available for this population.

Severe COVID-19: Drugs and Clinical Trials

By January of 2023, the COVID-19 pandemic had led to a reported total of 6,700,883 deaths and 662,631,114 cases worldwide. To date, there have been no effective therapies or standardized treatment schemes for this disease; therefore, the search for effective prophylactic and therapeutic strategies is a primary goal that must be addressed. This review aims to provide an analysis of the most efficient and promising therapies and drugs for the prevention and treatment of severe COVID-19, comparing their degree of success, scope, and limitations, with the aim of providing support to health professionals in choosing the best pharmacological approach. An investigation of the most promising and effective treatments against COVID-19 that are currently available was carried out by employing search terms including "Convalescent plasma therapy in COVID-19" or "Viral polymerase inhibitors" and "COVID-19" in the Clinicaltrials.gov and PubMed databases. From the current perspective and with the information available from the various clinical trials assessing the efficacy of different therapeutic options, we conclude that it is necessary to standardize certain variables-such as the viral clearance time, biomarkers associated with severity, hospital stay, requirement of invasive mechanical ventilation, and mortality rate-in order to facilitate verification of the efficacy of such treatments and to better assess the repeatability of the most effective and promising results.

Convalescent Plasma Treatment of Patients Previously Treated with B-Cell-Depleting Monoclonal Antibodies Suffering COVID-19 Is Associated with Reduced Re-Admission Rates

Patients receiving treatment with B-cell-depleting monoclonal antibodies, such as anti-CD20 monoclonal antibodies, such as rituximab and obinutuzumab, either for hematological disease or another diagnosis, such as a rheumatological disease, are at an increased risk for medical complications and mortality from COVID-19. Since inconsistencies persist regarding the use of convalescent plasma (CP), especially in the vulnerable patient population that has received previous treatment with B-cell-depleting monoclonal antibodies, further studies should be performed in thisdirection. The aim of the present study was to describe the characteristics of patients with previous use of B-cell-depleting monoclonal antibodies and describe the potential beneficial effects of CP use in terms of mortality, ICU admission and disease relapse. In this retrospective cohort study, 39 patients with previous use of B-cell-depleting monoclonal antibodies hospitalized in the COVID-19 department of a tertiary hospital in Greece were recorded and evaluated. The mean age was 66.3 years and 51.3% were male. Regarding treatment for COVID-19, remdesivir was used in 89.7%, corticosteroids in 94.9% and CP in 53.8%. In-hospital mortality was 15.4%. Patients who died were more likely to need ICU admission and also had a trend towards a longer hospital stay, even though the last did not reach statistical significance. Patients treated with CP had a lower re-admission rate for COVID-19 after discharge. Further studies should be performed to identify the role of CP in patients with treatment with B-cell-depleting monoclonal antibodies suffering from COVID-19.

High-Throughput Neutralization and Serology Assays Reveal Correlated but Highly Variable Humoral Immune Responses in a Large Population of Individuals Infected with SARS-CoV-2 in the US between March and August 2020

The ability to measure neutralizing antibodies on large scale can be important for understanding features of the natural history and epidemiology of infection, as well as an aid in determining the efficacy of interventions, particularly in outbreaks such as the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Because of the assay's rapid scalability and high efficiency, serology measurements that quantify the presence rather than function of serum antibodies often serve as proxies of immune protection. Here, we report the development of a high-throughput, automated fluorescence-based neutralization assay using SARS-CoV-2 virus to quantify neutralizing antibody activity in patient specimens. We performed large-scale testing of over 19,000 COVID-19 convalescent plasma (CCP) samples from patients who had been infected with SARS-CoV-2 between March and August 2020 across the United States. The neutralization capacity of the samples was moderately correlated with serological measurements of anti-receptor-binding domain (RBD) IgG levels. The neutralizing antibody levels within these convalescent-phase serum samples were highly variable against the original USA-WA1/2020 strain with almost 10% of individuals who had had PCR-confirmed SARS-CoV-2 infection having no detectable antibodies either by serology or neutralization, and ~1/3 having no or low neutralizing activity. Discordance between neutralization and serology measurements was mainly due to the presence of non-IgG RBD isotypes. Meanwhile, natural infection with the earliest SARS-CoV-2 strain USA-WA1/2020 resulted in weaker neutralization of subsequent B.1.1.7 (alpha) and the B.1.351 (beta) variants, with 88% of samples having no activity against the BA.1 (omicron) variant. IMPORTANCE The ability to directly measure neutralizing antibodies on live SARS-CoV-2 virus in individuals can play an important role in understanding the efficacy of therapeutic interventions or vaccines. In contrast to functional neutralization assays, serological assays only quantify the presence of antibodies as a proxy of immune protection. Here, we have developed a high-throughput, automated neutralization assay for SARS-CoV-2 and measured the neutralizing activity of ~19,000 COVID-19 convalescent plasma (CCP) samples collected across the United States between March and August of 2020. These data were used to support the FDA's interpretation of CCP efficacy in patients with SARS-CoV-2 infection and their issuance of emergency use authorization of CCP in 2020.

Use of COVID-19 Convalescent Plasma for Treatment of Symptomatic SARS-CoV-2 Infection at a Children's Hospital: A Contribution to a Still Inadequate Body of Evidence

Data on COVID-19 convalescent plasma (CCP) safety and efficacy in children and young adults are limited. This single-center prospective, open-label trial evaluates CCP safety, neutralizing antibody kinetics, and outcomes in children and young adults with moderate/severe COVID-19 (April 2020-March 2021). A total of 46 subjects received CCP; 43 were included in the safety analysis (SAS); 7.0% < 2 years old, 2.3% 2-<6, 27.9% 6-<12, 39.5% 12-<19, and 23.3% > 19 years old; 28 were included in the antibody kinetic analysis (AbKS); 10.7% < 2 years old, 10.7% 6-<12, 53.8% 12-<19, and 25.0% > 19 years old. No adverse events occurred. The median COVID-19 severity score improved (5.0 pre-CCP to 1.0 by day 7; p < 0.001). A rapid increase in the median percentage of inhibition was observed in AbKS (22.5% (13.0%, 41.5%) pre-infusion to 52% (23.7%, 72%) 24 h post-infusion); a similar increase was observed in nine immune-competent subjects (28% (23%, 35%) to 63% (53%, 72%)). The inhibition percentage increased until day 7 and persisted at 21 and 90 days. CCP is well tolerated in children and young adults, providing rapid and robust increased antibodies. CCP should remain a therapeutic option for this population for whom vaccines are not fully available and given that the safety and efficacy of existing monoclonal antibodies and antiviral agents have not been established.

Transfusing Convalescent Plasma as Post-Exposure Prophylaxis Against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection: A Double-Blinded, Phase 2 Randomized, Controlled Trial

BACKGROUND

The efficacy of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) convalescent plasma (CCP) for preventing infection in exposed, uninfected individuals is unknown. CCP might prevent infection when administered before symptoms or laboratory evidence of infection.

METHODS

This double-blinded, phase 2 randomized, controlled trial (RCT) compared the efficacy and safety of prophylactic high titer (≥1:320 by Euroimmun ELISA) CCP with standard plasma. Asymptomatic participants aged ≥18 years with close contact exposure to a person with confirmed coronavirus disease 2019 (COVID-19) in the previous 120 hours and negative SARS-CoV-2 test within 24 hours before transfusion were eligible. The primary outcome was new SARS-CoV-2 infection.

RESULTS

In total, 180 participants were enrolled; 87 were assigned to CCP and 93 to control plasma, and 170 transfused at 19 sites across the United States from June 2020 to March 2021. Two were excluded for screening SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR) positivity. Of the remaining 168 participants, 12/81 (14.8%) CCP and 13/87 (14.9%) control recipients developed SARS-CoV-2 infection; 6 (7.4%) CCP and 7 (8%) control recipients developed COVID-19 (infection with symptoms). There were no COVID-19-related hospitalizations in CCP and 2 in control recipients. Efficacy by restricted mean infection free time (RMIFT) by 28 days for all SARS-CoV-2 infections (25.3 vs 25.2 days; P = .49) and COVID-19 (26.3 vs 25.9 days; P = .35) was similar for both groups.

CONCLUSIONS

Administration of high-titer CCP as post-exposure prophylaxis, although appearing safe, did not prevent SARS-CoV-2 infection.

CLINICAL TRIALS REGISTRATION

NCT04323800.

Evaluation of Convalescent Plasma in the Management of Critically Ill COVID-19 Patients (with No Detectable Neutralizing Antibodies Nab) in Kashmir, India

BACKGROUND

For centuries, convalescent plasma (CP) has been recommended to treat a diverse set of viral diseases. Therefore, the present study was undertaken to evaluate the effectiveness of CP in critically ill COVID-19 patients.

METHODS AND MATERIALS

From 23 March 2021 to 29 December 2021, an open-label, prospective cohort, single-centre study was conducted at Chest Disease Hospital, Jammu and Kashmir, Srinagar. Patients with severe manifestation of coronavirus disease 2019 (COVID-19) under BST (best standard treatment) +CP were prospectively observed in order to evaluate effectiveness of CP therapy and historical control under BST were used as the control group Results: A total of 1667 patients were found positive for COVID-19. Of these, 873 (52.4%), 431 (28.8%), and 363 (21.8%) were moderately, severely, and critically ill, respectively. On 35th day post-infusion of CP, all-cause mortality was higher in the BST (best standard treatment) +CP group 12 (37.5%) compared to 127 (35%) in the BST group with an odds ratio (OR) of 1.4 and hazard ratio (HR) (95% CI: 1.08-1.79, p = 0.06). Similarly, 7 (21.9) patients in the BST+CP group and 121 (33.3) patients in the BST group showed the transition from critically ill to moderate disease with subhazard ratio (s-HR 1.37) (95% CI: 1.03-2.9).

CONCLUSIONS

In the present study, we could not find any significant difference in the CP group and BST +CP in primary outcome of reducing all-cause mortality in critically ill patients with negligible Nabs levels. However, beneficial results were observed with use of CP in a limited number of secondary outcomes which includes days of hospitalization, negative conversion of SARS-CoV-2 on basis of RT-PCR on 7th day and 14th day, need for invasive mechanical ventilation on 14th day post-CP treatment, and resolution of shortness of breath.

Protective roles and protective mechanisms of neutralizing antibodies against SARS-CoV-2 infection and their potential clinical implications

Neutralizing antibodies (NAbs) are central players in the humoral immunity that defends the body from SARS-CoV-2 infection by blocking viral entry into host cells and neutralizing their biological effects. Even though NAbs primarily work by neutralizing viral antigens, on some occasions, they may also combat the SARS-CoV-2 virus escaping neutralization by employing several effector mechanisms in collaboration with immune cells like natural killer (NK) cells and phagocytes. Besides their prophylactic and therapeutic roles, antibodies can be used for COVID-19 diagnosis, severity evaluation, and prognosis assessment in clinical practice. Furthermore, the measurement of NAbs could have key implications in determining individual or herd immunity against SARS-CoV-2, vaccine effectiveness, and duration of the humoral protective response, as well as aiding in the selection of suitable individuals who can donate convalescent plasma to treat infected people. Despite all these clinical applications of NAbs, using them in clinical settings can present some challenges. This review discusses the protective functions, possible protective mechanisms against SARS-CoV-2, and potential clinical applications of NAbs in COVID-19. This article also highlights the possible challenges and solutions associated with COVID-19 antibody-based prophylaxis, therapy, and vaccination.

Effects of convalescent plasma infusion on the ADAMTS13-von Willebrand factor axis and endothelial integrity in patients with severe and critical COVID-19

Background

Convalescent plasma infusion (CPI) was given to patients with COVID-19 during the early pandemic with mixed therapeutic efficacy. However, the impacts of CPI on the ADAMTS13-von Willebrand factor (VWF) axis and vascular endothelial functions are not known.

Objectives

To determine the impacts of CPI on the ADAMTS13-VWF axis and vascular endothelial functions.

Methods

Sixty hospitalized patients with COVID-19 were enrolled in the study; 46 received CPI and 14 received no CPI. Plasma ADAMTS13 activity, VWF antigen, endothelial syndecan-1, and soluble thrombomodulin (sTM) were assessed before and 24 hours after treatment.

Results

Patients with severe and critical COVID-19 exhibited significantly lower plasma ADAMTS13 activity than the healthy controls. Conversely, these patients showed a significantly increased VWF antigen. This resulted in markedly reduced ratios of ADAMTS13 to VWF in these patients. The levels of plasma ADAMTS13 activity in each patient remained relatively constant throughout hospitalization. Twenty-four hours following CPI, plasma ADAMTS13 activity increased by ∼12% from the baseline in all patients and ∼21% in those who survived. In contrast, plasma levels of VWF antigen varied significantly over time. Patients who died exhibited a significant reduction of plasma VWF antigen from the baseline 24 hours following CPI, whereas those who survived did not. Furthermore, patients with severe and critical COVID-19 showed significantly elevated plasma levels of syndecan-1 and sTM, similar to those found in patients with immune thrombotic thrombocytopenic purpura. Both syndecan-1 and sTM levels were significantly reduced 24 hours following CPI.

Conclusion

Our results demonstrate the relative deficiency of plasma ADAMTS13 activity and endothelial damage in patients with severe and critical COVID-19, which could be modestly improved following CPI therapy.

Early Treatment with Monoclonal Antibodies or Convalescent Plasma Reduces Mortality in Non-Vaccinated COVID-19 High-Risk Patients

Vulnerable patients such as immunosuppressed or elderly patients are at high risk for a severe course of COVID-19 upon SARS-CoV-2 infection. Immunotherapy with SARS-CoV-2 specific monoclonal antibodies (mAb) or convalescent plasma represents a considerable treatment option to protect these patients from a severe or lethal course of infection. However, monoclonal antibodies are not always available or less effective against emerging SARS-CoV-2 variants. Convalescent plasma is more commonly available and may represent a good treatment alternative in low-income countries. We retrospectively evaluated outcomes in individuals treated with mAbs or convalescent plasma and compared the 30-day overall survival with a patient cohort that received supportive care due to a lack of SARS-CoV-2 specific therapies between March 2020 and April 2021. Our data demonstrate that mAb treatment is highly effective in preventing severe courses of SARS-CoV-2 infection. All patients treated with mAb survived. Treatment with convalescent plasma improved overall survival to 82% compared with 61% in patients without SARS-CoV-2 targeted therapy. Our data indicate that early convalescent plasma treatment may be an option to improve the overall survival of high-risk COVID-19 patients. This is especially true when other antiviral drugs are not available or their efficacy is significantly reduced, which may be the case with emerging SARS-CoV-2 variants.

CURRENT ASPECTS OF ETIOTROPIC COVID-19 THERAPY

Since the beginning of the pandemic, repeated attempts have been made to develop etiotropic therapy for a novel coronavirus infection. Hydroxychloroquine, lopinavir/ritonavir, etc. derivatives were used as antiviral agents, however, they demonstrated a low efficiency and an insufficient safety. In this connection, other groups of drugs with a more effective and safe pharmacological profile are currently being actively used.

The aim of the study was to analyze the literature references on the efficacy and safety of antiviral drugs for the COVID-19 treatment.

Materials and methods. When searching for the materials for the review article writing, such abstract databases as PubMed, Google Scholar, e-Library were used. The search was carried out on publications for the period from January 2020 to september 2022. The key queries were: COVID-19, etiotropic therapy; immunological drugs; antiviral drugs; interferons.

Results. Currently, there are various degrees of effective etiotropic drugs for the treatment of COVID-19 patients. The review has considered a few groups of drugs that are of interest from the point of view of etiotropic therapy: immunological drugs (anticovid plasma, the drugs based on antiviral antibodies, the drugs of recombinant interferons-α2 and -β1, as well as interferon inducers, i.e., the drugs based on double-stranded RNA sodium salt, and others); drugs that block the penetration of the virus into the cell (umifenovir); the drugs that disrupt the process of the viral replication (favipiravir, remdesivir, molnupiravir, nirmatrelvir/ritonavir).

Conclusion. Synthetic antivirals, in particular favipiravir, molnupiravir, remdesivir, and nirmatrelvir/ritonavir, have the largest evidence base for their efficacy and safety. The search for new effective and safe etiotropic drugs for the treatment of COVID-19, as well as the collection and analysis of post-registration data on the drugs already used in clinical practice, continues.

Evaluation of a COVID-19 convalescent plasma program at a U.S. academic medical center

Amidst the therapeutic void at the onset of the COVID-19 pandemic, a critical mass of scientific and clinical interest coalesced around COVID-19 convalescent plasma (CCP). To date, the CCP literature has focused largely on safety and efficacy outcomes, but little on implementation outcomes or experience. Expert opinion suggests that if CCP has a role in COVID-19 treatment, it is early in the disease course, and it must deliver a sufficiently high titer of neutralizing antibodies (nAb). Missing in the literature are comprehensive evaluations of how local CCP programs were implemented as part of pandemic preparedness and response, including considerations of the core components and personnel required to meet demand with adequately qualified CCP in a timely and sustained manner. To address this gap, we conducted an evaluation of a local CCP program at a large U.S. academic medical center, the University of North Carolina Medical Center (UNCMC), and patterned our evaluation around the dimensions of the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework to systematically describe key implementation-relevant metrics. We aligned our evaluation with program goals of reaching the target population with severe or critical COVID-19, integrating into the structure of the hospital-wide pandemic response, adapting to shifting landscapes, and sustaining the program over time during a compassionate use expanded access program (EAP) era and a randomized controlled trial (RCT) era. During the EAP era, the UNCMC CCP program was associated with faster CCP infusion after admission compared with contemporaneous affiliate hospitals without a local program: median 29.6 hours (interquartile range, IQR: 21.2-48.1) for the UNCMC CCP program versus 47.6 hours (IQR 32.6-71.6) for affiliate hospitals; (P<0.0001). Sixty-eight of 87 CCP recipients in the EAP (78.2%) received CCP containing the FDA recommended minimum nAb titer of ≥1:160. CCP delivery to hospitalized patients operated with equal efficiency regardless of receiving treatment via a RCT or a compassionate-use mechanism. It was found that in a highly resourced academic medical center, rapid implementation of a local CCP collection, treatment, and clinical trial program could be achieved through re-deployment of highly trained laboratory and clinical personnel. These data provide important pragmatic considerations critical for health systems considering the use of CCP as part of an integrated pandemic response.

Neutralizing and enhancing antibodies against SARS-CoV-2

The high transmissibility and rapid global spread of SARS-CoV-2 since 2019 has led to a huge burden on healthcare worldwide. Anti-SARS-CoV-2 neutralizing antibodies play an important role in not only protecting against infection but also in clearing the virus and are essential to providing long-term immunity. On the other hand, antibodies against the virus are not always protective. With the emergence of SARS-CoV-2 immune escape variants, vaccine design strategies as well as antibody-mediated therapeutic approaches have become more important. We review some of the findings on SARS-CoV-2 antibodies, focusing on both basic research and clinical applications.

The clinical outcomes of high neutralizing antibodies titer convalescent plasma therapy in early developed severe COVID-19 patients; a case-control study

BACKGROUND

Coronavirus disease 2019 (COVID-19) causes life-threatening pneumonia. Convalescent plasma therapy (CPT) is expected to be the effective COVID-19 treatment for passive immunity. The high neutralizing antibodies titer of CPT is needed to prove the benefit in early developed severe COVID-19.

OBJECTIVE

This case-control study evaluated transfusion efficacy and adverse events with high-titer (≥ 1:320) COVID-19 convalescent plasma compared with standard care alone in severe COVID-19 pneumonia.

RESULTS

Among 107 severe COVID-19 patients, 55 received CPT plus standard care, and 52 received standard care alone. All-cause mortality was 15.3% in the CPT group compared with 85.4% in the standard care group (p < 0.001). Univariate and multivariate analyses revealed reduced mortality with CPT (HR 0.14; 95% CI 0.07-0.31; p < 0.001 and HR 0.26; 95% CI 0.08-0.79; p = 0.018, respectively). CPT resulted in decreased use of mechanical ventilation, duration of supplemental oxygen, and high-flow oxygen requirement. Clinical and radiological outcomes improved.

CONCLUSIONS

Immediate high neutralizing antibody titer CPT is safe and reduces mortality in early developed severe COVID-19 patients. The benefit of CPT in the early course of illness is challenging and requires additional study. Trial registration Thai clinical trials registry (TCTR) no. 20220101003.

Validation of Viral Inactivation Protocols for Therapeutic Blood Products against Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-COV-2)

Therapeutic blood products including convalescent plasma/serum and immunoglobulins concentrated from convalescent plasma, such as intravenous immunoglobulins or hyperimmune globulins, and monoclonal antibodies are passive immunotherapy options for novel coronavirus disease 2019 (COVID-19). They have been shown to improve the clinical status and biological and radiological parameters in some groups of COVID-19 patients. However, blood products are still potential sources of virus transmission in recipients. The use of pathogen reduction technology (PRT) should increase the safety of the products. The purpose of this study was to determine the impact of solvent/detergents (S/D) procedures on SARS-COV-2 infectivity elimination in the plasma of donors but also on COVID-19 convalescent serum (CCS) capacity to neutralize SARS-COV-2 infectivity. In this investigation, S/D treatment for all experiments was performed at a shortened process time (30 min). We first evaluated the impact of S/D treatments (1% TnBP/1% TritonX-45 and 1% TnBP/1% TritonX-100) on the inactivation of SARS-COV-2 pseudoparticles (SARS-COV-2pp)-spiked human plasma followed by S/D agent removal using a Sep-Pak Plus C18 cartridge. Both treatments were able to completely inactivate SARS-COV-2pp infectivity to an undetectable level. Moreover, the neutralizing activity of CCS against SARS-COV-2pp was preserved after S/D treatments. Our data suggested that viral inactivation methods using such S/D treatments could be useful in the implementation of viral inactivation/elimination processes of therapeutic blood products against SARS-COV-2.

Efficacy and Safety of COVID-19 Convalescent Plasma in Hospitalized Patients-An Open-Label Phase II Clinical Trial

Background: COVID-19 convalescent plasma (CCP) is an important antiviral option for selected patients with COVID-19. Materials and Methods: In this open-label, phase 2, clinical trial conducted from 30 April 2020 till 10 May 2021 in the Republic of North Macedonia, we evaluated the efficacy and safety of CCP in hospitalized patients. Treatment was with a single unit of CCP having an anti-RBD IgG concentration higher than 5 AU/mL. Results: There were 189 patients that completed the study, of which 65 (34.4%) had WHO 8-point clinical progression scale score of 3 (requiring hospital care but not oxygen support), 65 (34.4%) had a score of 4 (hospitalized and requiring supplemental oxygen by mask or nasal prongs), and 59 (31.2%) had a score of 5 (hospitalized and requiring supplemental oxygen by non-invasive ventilation or high-flow oxygen). Mean age was 57 years (range 22−94), 78.5% were males, 80.4% had elevated body mass index, and 70.9% had comorbidity. Following CCP transfusion, we observed clinical improvement with increase rates in oxygenation-free days of 32.3% and 58.5% at 24 h and seven days after CCP transfusion, a decline in WHO scores, and reduced progression to severe disease (only one patient was admitted to ICU after CCP transfusion). Mortality in the entire cohort was 11.6% (22/189). We recorded 0% mortality in WHO score 3 (0/65) and in patients that received CCP transfusion in the first seven days of disease, 4.6% mortality in WHO score 4 (3/65), and 30.5% mortality in WHO score 5 (18/59). Mortality correlated with WHO score (Chi-square 19.3, p < 0.001) and with stay in the ICU (Chi-square 55.526, p ≤ 0.001). No severe adverse events were reported. Conclusions: This study showed that early administration of CCP to patients with moderate disease was a safe and potentially effective treatment for hospitalized COVID-19 patients. The trial was registered at clinicaltrials.gov (NCT04397523).

Platelets and Sera from Donors of Convalescent Plasma after Mild COVID-19 Show No Procoagulant Phenotype

Coronavirus disease-2019 (COVID-19) is associated with increased thromboembolic complications. Long-term alteration in the coagulation system after acute COVID-19 infection is still a subject of research. Furthermore, the effect of sera from convalescent subjects on platelets is not known. In this study, we investigated platelet phenotype, coagulation, and fibrinolysis in COVID-19 convalescent plasma (CCP) donors and analyzed convalescent sera-induced effects on platelets. We investigated CCP donors who had a history of mild COVID-19 infection and donors who did not have COVID-19 were used as controls. We analyzed phosphatidylserine (PS) externalization, CD62p expression, and glycoprotein VI (GPVI) shedding both in platelet-rich plasma (PRP) and after incubation of washed healthy platelets with donors' sera using flow cytometry. Coagulation and fibrinolysis systems were assessed with thromboelastometry. Forty-seven CCP donors (22 males, 25 females; mean age (±SD): 41.4 ± 13.7 years) with a history of mild COVID-19 infection were included. Median duration after acute COVID-19 infection was 97 days (range, 34–401). We did not find an increased PS externalization, CD62p expression, or GPVI shedding in platelets from CCP donors. Sera from CCP donors did not induce PS externalization or GPVI shedding in healthy platelets. Sera-induced CD62p expression was slightly, albeit statistically significantly, lower in CCP donors than in plasma donors without a history of COVID-19. One patient showed increased maximum clot firmness and prolonged lysis time in thromboelastometry. Our findings suggest that procoagulant platelet phenotype is not present after mild COVID-19. Furthermore, CCP sera do not affect the activation status of platelets.

Cardiovascular Factors Associated with COVID-19 from an International Registry of Primarily Japanese Patients

Aims: We developed an international registry to examine cardiovascular complications of COVID-19. Methods: A REDCap form was created in March 2020 at Mayo Clinic in collaboration with the International Society of Cardiomyopathy, Myocarditis and Heart Failure (ISCMF) and data were entered from April 2020 through April 2021. Results: Of the 696 patients in the COVID-19 Registry, 411 (59.2%) were male and 283 (40.8%) were female, with a sex ratio of 1.5:1 male to female. In total, 95.5% of the patients were from Japan. The average age was 52 years with 31.5% being >65 years of age. COVID-19 patients with a history of cardiovascular disease (CVD) had more pre-existing conditions including type II diabetes (p < 0.0001), cancer (p = 0.0003), obesity (p = 0.001), and kidney disease (p = 0.001). They also had a greater mortality of 10.1% compared to 1.7% in those without a history of CVD (p < 0.0001). The most common cardiovascular conditions in patients with a history of CVD were hypertension (33.7%), stroke (5.7%) and arrhythmias (5.1%). We found that troponin T, troponin I, brain natriuretic peptide (BNP), N-terminal pro-BNP (NT-proBNP), C-reactive protein (CRP), IL-6 and lambda immunoglobulin free light chains (Ig FLC) were elevated above reference levels in patients with COVID-19. Myocarditis is known to occur mainly in adults under the age of 50, and when we examined biomarkers in patients that were ≤50 years of age and had no history of CVD we found that a majority of patients had elevated levels of troponin T (71.4%), IL-6 (59.5%), creatine kinase/CK-MB (57.1%), D-dimer (57.8%), kappa Ig FLC (75.0%), and lambda Ig FLC (71.4%) suggesting myocardial injury and possible myocarditis. Conclusions: We report the first findings to our knowledge of cardiovascular complications from COVID-19 in the first year of the pandemic in a predominantly Japanese population. Mortality was increased by a history of CVD and pre-existing conditions including type II diabetes, cancer, obesity, and kidney disease. Our findings indicate that even in cases where no abnormalities are found in ECG or ultrasound cardiography that myocardial damage may occur, and cardiovascular and inflammatory biomarkers may be useful for the diagnosis.

COVID-19 Convalescent Plasma and Clinical Trials: Understanding Conflicting Outcomes

Convalescent plasma (CP) recurs as a frontline treatment in epidemics because it is available as soon as there are survivors. The COVID-19 pandemic represented the first large-scale opportunity to shed light on the mechanisms of action, safety, and efficacy of CP using modern evidence-based medicine approaches. Studies ranging from observational case series to randomized controlled trials (RCTs) have reported highly variable efficacy results for COVID-19 CP (CCP), resulting in uncertainty. We analyzed variables associated with efficacy, such as clinical settings, disease severity, CCP SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) antibody levels and function, dose, timing of administration (variously defined as time from onset of symptoms, molecular diagnosis, diagnosis of pneumonia, or hospitalization, or by serostatus), outcomes (defined as hospitalization, requirement for ventilation, clinical improvement, or mortality), CCP provenance and time for collection, and criteria for efficacy. The conflicting trial results, along with both recent WHO guidelines discouraging CCP usage and the recent expansion of the FDA emergency use authorization (EUA) to include outpatient use of CCP, create confusion for both clinicians and patients about the appropriate use of CCP. A review of 30 available RCTs demonstrated that signals of efficacy (including reductions in mortality) were more likely if the CCP neutralizing titer was >160 and the time to randomization was less than 9 days. The emergence of the Omicron variant also reminds us of the benefits of polyclonal antibody therapies, especially as a bridge to the development and availability of more specific therapies.

Convalescent plasma and COVID-19: Time for a second-second look?

In this short narrative, we highlight some of our experiences leading the US Convalescent Plasma Program at the beginning of the pandemic in the spring and summer of 2020. This includes a brief summary of how the program emerged and high-level lessons we learned. We also share our impressions about why convalescent plasma was used at scale in the United States, early in the pandemic and share ideas that might inform the use of convalescent plasma in future outbreaks of novel infectious diseases.

COVID-19 management landscape: A need for an affordable platform to manufacture safe and efficacious biotherapeutics and prophylactics for the developing countries

To gain world-wide control over COVID-19 pandemic, it is necessary to have affordable and accessible vaccine and monoclonal antibody technologies across the globe. In comparison to the western countries, Asian and African countries have less percentage of vaccination done which warrants urgent attention. Global manufacturer production capacities, dependency on advanced nations for the supply of vaccines or the raw material, national economy, limited research facilities, and logistics could be the factors. This review article elaborates the existing therapeutic and prophylactic strategies available for COVID-19, currently adopted vaccine and monoclonal antibody platforms for SARS-CoV-2 along with the approaches to bridge the gap prevailing in the challenges faced by low- and middle-income countries. We believe adoption of yeast-derived P. pastoris technology can help in developing safe, proven, easy to scale-up, and affordable recombinant vaccine or monoclonal antibodies against SARS-CoV-2. This platform has the advantage of not requiring a dedicated or specialized facility making it an affordable option using existing manufacturing facilities, without significant additional capital investments. Besides, the technology platform of multiantigen vaccine approach and monoclonal antibody cocktail will serve as effective weapons to combat the threat posed by the SARS-CoV-2 variants. Successful development of vaccines and monoclonal antibodies using such a technology will lead to self-sufficiency of these nations in terms of availability of vaccines and monoclonal antibodies.

Characterization of Pathogen Inactivated COVID ‐19 Convalescent Plasma and Responses in Transfused Patients

Background

Efficacy of donated COVID‐19 convalescent plasma (dCCP) is uncertain and may depend on antibody titers, neutralizing capacity, timing of administration, and patient characteristics.

Study Design and Methods

In a single‐center hypothesis‐generating prospective case–control study with 1:2 matched dCCP recipients to controls according to disease severity at day 1, hospitalized adults with COVID‐19 pneumonia received 2 × 200 ml pathogen‐reduced treated dCCP from 2 different donors. We evaluated severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) antibodies in COVID‐19 convalescent plasma donors and recipients using multiple antibody assays including a Coronavirus antigen microarray (COVAM), and binding and neutralizing antibody assays. Outcomes were dCCP characteristics, antibody responses, 28‐day mortality, and dCCP ‐related adverse events in recipients.

Results

Eleven of 13 dCCPs (85%) contained neutralizing antibodies (nAb). PRT did not affect dCCP antibody activity. Fifteen CCP recipients and 30 controls (median age 64 and 65 years, respectively) were enrolled. dCCP recipients received 2 dCCPs from 2 different donors after a median of one hospital day and 11 days after symptom onset. One dCCP recipient (6.7%) and 6 controls (20%) died (p = 0.233). We observed no dCCP‐related adverse events. Transfusion of unselected dCCP led to heterogeneous SARS CoV‐2 antibody responses. COVAM clustered dCCPs in 4 distinct groups and showed endogenous immune responses to SARS‐CoV‐2 antigens over 14–21 days post dCCP in all except 4 immunosuppressed recipients.

Discussion

PRT did not impact dCCP anti‐virus neutralizing activity. Transfusion of unselected dCCP did not impact survival and had no adverse effects. Variable dCCP antibodies and post‐transfusion antibody responses indicate the need for controlled trials using well‐characterized dCCP with informative assays.

Lack of efficacy of convalescent plasma in COVID-19 patients with concomitant hematological malignancies: An Italian retrospective study

A multicenter retrospective study was designed to assess clinical outcome of COVID-19 in patients with hematological malignancies (HM) following treatment with anti-SARS-CoV-2 convalescent plasma (CP) or standard of care therapy. To this aim, a propensity score matching was used to assess the role of non-randomized administration of CP in this high-risk cohort of patients from the Italian Hematology Alliance on COVID-19 (ITA-HEMA-COV) project, now including 2049 untreated control patients. We investigated 30- and 90-day mortality, rate of admission to intensive care unit, proportion of patients requiring mechanical ventilatory support, hospitalization time, and SARS-CoV-2 clearance in 79 CP recipients and compared results with 158 propensity score-matched controls. Results indicated a lack of efficacy of CP in the study group compared with the untreated group, thus confirming the negative results obtained from randomized studies in immunocompetent individuals with COVID-19. In conclusion, this retrospective analysis did not meet the primary and secondary end points in any category of immunocompromized patients affected by HM.

Convalescent plasma therapy for patients with severe COVID-19: A case series study

Coronavirus disease 2019 (COVID-19) is a novel acute respiratory infectious disease that can lead to multiple-organ dysfunction in patients with severe disease. However, there is a lack of effective antiviral drugs for COVID-19. Herein, we investigated the efficacy and safety of convalescent plasma (CP) therapy for treating severe COVID-19 in an attempt to explore new therapeutic methods. The clinical data of 3 imported patients with severe COVID-19 who underwent treatment with CP and who were quarantined and treated in a designated COVID-19 hospital from March 2020 to April 2020 were collected and analyzed. The 3 patients, including a 57-year-old male, 65-year-old female, and 59-year-old female, were clinically classified as having severe COVID-19. The main underlying diseases included hypertension, diabetes, sequelae of cerebral infarction, and postoperative thyroid adenoma. The common symptoms included cough, fever, and shortness of breath. All patients received antiviral drugs and other supportive treatments. Additionally, CP treatment was administered. At 48 to 72 hours after the CP transfusion, all 3 of the patients exhibited an improvement and alleviation of symptoms, an elevated arterial oxygen saturation, and decreased C-reactive protein and interleukin-6 levels. The counts of the total lymphocytes and T lymphocytes (CD3+) and their subsets (CD4 + and CD8+) were also obviously increased. Repeated chest computed tomography also revealed obvious absorption of the lesions in the bilateral lungs. Only 1 patient had a mild allergic reaction during the CP infusion, but no severe adverse reactions were observed. The early treatment with CP in patients with severe COVID-19 can rapidly improve the condition of the patients, and CP therapy is generally effective and safe.

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

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

Abnormal antibodies to self-carbohydrates in SARS-CoV-2-infected patients

Our immune system is critical for preventing and treating SARS-CoV-2 infections, but aberrant immune responses can have deleterious effects. While antibodies to glycans could recognize the virus and influence the clinical outcome, little is known about their roles. Using a carbohydrate antigen microarray, we profiled serum antibodies in healthy control subjects and COVID-19 patients from two separate cohorts. COVID-19 patients had numerous autoantibodies to self-glycans, including antiganglioside antibodies that can cause neurological disorders. Additionally, nearly all antiglycan IgM signals were lower in COVID-19 patients, indicating a global dysregulation of this class of antibodies. Autoantibodies to certain N-linked glycans correlated with more severe disease, as did low levels of antibodies to the Forssman antigen and ovalbumin. Collectively, this study indicates that expanded testing for antiglycan antibodies could be beneficial for clinical analysis of COVID-19 patients and illustrates the importance of including host and viral carbohydrate antigens when studying immune responses to viruses.

Antibodies from convalescent plasma promote SARS-CoV-2 clearance in individuals with and without endogenous antibody response

BACKGROUNDNeutralizing antibodies are considered a key correlate of protection by current SARS-CoV-2 vaccines. The manner in which human infections respond to therapeutic SARS-CoV-2 antibodies, including convalescent plasma therapy, remains to be fully elucidated.METHODSWe conducted a proof-of-principle study of convalescent plasma therapy based on a phase I trial in 30 hospitalized COVID-19 patients with a median interval between onset of symptoms and first transfusion of 9 days (IQR, 7-11.8 days). Comprehensive longitudinal monitoring of the virological, serological, and disease status of recipients allowed deciphering of parameters on which plasma therapy efficacy depends.RESULTSIn this trial, convalescent plasma therapy was safe as evidenced by the absence of transfusion-related adverse events and low mortality (3.3%). Treatment with highly neutralizing plasma was significantly associated with faster virus clearance, as demonstrated by Kaplan-Meier analysis (P = 0.034) and confirmed in a parametric survival model including viral load and comorbidity (adjusted hazard ratio, 3.0; 95% CI, 1.1-8.1; P = 0.026). The onset of endogenous neutralization affected viral clearance, but even after adjustment for their pretransfusion endogenous neutralization status, recipients benefitted from plasma therapy with high neutralizing antibodies (hazard ratio, 3.5; 95% CI, 1.1-11; P = 0.034).CONCLUSIONOur data demonstrate a clear impact of exogenous antibody therapy on the rapid clearance of viremia before and after onset of the endogenous neutralizing response, and point beyond antibody-based interventions to critical laboratory parameters for improved evaluation of current and future SARS-CoV-2 therapies.TRIAL REGISTRATIONClinicalTrials.gov NCT04869072.FUNDINGThis study was funded via an Innovation Pool project by the University Hospital Zurich; the Swiss Red Cross Glückskette Corona Funding; Pandemiefonds of the UZH Foundation; and the Clinical Research Priority Program "Comprehensive Genomic Pathogen Detection" of the University of Zurich.

The Role of Antibodies in the Treatment of SARS-CoV-2 Virus Infection, and Evaluating Their Contribution to Antibody-Dependent Enhancement of Infection

Antibodies play a crucial role in the immune response, in fighting off pathogens as well as helping create strong immunological memory. Antibody-dependent enhancement (ADE) occurs when non-neutralising antibodies recognise and bind to a pathogen, but are unable to prevent infection, and is widely known and is reported as occurring in infection caused by several viruses. This narrative review explores the ADE phenomenon, its occurrence in viral infections and evaluates its role in infection by SARS-CoV-2 virus, which causes coronavirus disease 2019 (COVID-19). As of yet, there is no clear evidence of ADE in SARS-CoV-2, though this area is still subject to further study.

Reinforcement of the Standard Therapy with Two Infusions of Convalescent Plasma for Patients with COVID-19: A Randomized Clinical Trial

Background: The aim was to evaluate the reinforcement of the standard therapy with hyperimmune plasma (HP) in Coronavirus-19 disease (COVID-19) patients. Methods: Open-label, multicenter, randomized clinical trial performed in three hospitals in the Balearic Islands. Non-severe COVID-19 hospitalized patients with clinical time evolution equal to/less than 7 days were included, and randomized in: plasma group (PG) (n = 37), receiving 600 mL divided into two doses from convalescent plasma donor, administered on days 1 and 2 after the enrollment; and control group (CG) (n = 17). Primary outcome was the time for clinical improvement within 21 days, defined as patient achievement of categories 8, 7, and 6 in the Adaptive COVID-19 Treatment Trial scale (ACTT). The trial was terminated early due to the impossibility of recruitment due to the pandemic. Results: PG presented better scores on the ACTT scale at 7 days after HP infusion, whereas CG was needed 14 days to achieve similar results. The plasma infusion was safe. Conclusions: Despite the tendency observed in the plasma group to achieve slightly earlier better physical condition compared with the standard treatment alone. The administration of HP has been shown to be a safe therapy. No robust evidence was found to affirm a therapeutic effect of the early administration of two infusions of HP for non-severe COVID-19 infected patients. The interpretation is limited by the early termination of the trial, which resulted in a small sample size.

Early Outpatient Treatment for Covid-19 with Convalescent Plasma

BACKGROUND

Polyclonal convalescent plasma may be obtained from donors who have recovered from coronavirus disease 2019 (Covid-19). The efficacy of this plasma in preventing serious complications in outpatients with recent-onset Covid-19 is uncertain.

METHODS

In this multicenter, double-blind, randomized, controlled trial, we evaluated the efficacy and safety of Covid-19 convalescent plasma, as compared with control plasma, in symptomatic adults (≥18 years of age) who had tested positive for severe acute respiratory syndrome coronavirus 2, regardless of their risk factors for disease progression or vaccination status. Participants were enrolled within 8 days after symptom onset and received a transfusion within 1 day after randomization. The primary outcome was Covid-19-related hospitalization within 28 days after transfusion.

RESULTS

Participants were enrolled from June 3, 2020, through October 1, 2021. A total of 1225 participants underwent randomization, and 1181 received a transfusion. In the prespecified modified intention-to-treat analysis that included only participants who received a transfusion, the primary outcome occurred in 17 of 592 participants (2.9%) who received convalescent plasma and 37 of 589 participants (6.3%) who received control plasma (absolute risk reduction, 3.4 percentage points; 95% confidence interval, 1.0 to 5.8; P = 0.005), which corresponded to a relative risk reduction of 54%. Evidence of efficacy in vaccinated participants cannot be inferred from these data because 53 of the 54 participants with Covid-19 who were hospitalized were unvaccinated and 1 participant was partially vaccinated. A total of 16 grade 3 or 4 adverse events (7 in the convalescent-plasma group and 9 in the control-plasma group) occurred in participants who were not hospitalized.

CONCLUSIONS

In participants with Covid-19, most of whom were unvaccinated, the administration of convalescent plasma within 9 days after the onset of symptoms reduced the risk of disease progression leading to hospitalization. (Funded by the Department of Defense and others; CSSC-004 ClinicalTrials.gov number, NCT04373460.).

Antibody-Mediated Neutralization of SARS-CoV-2

Neutralizing antibodies can block infection, clear pathogens, and are essential to provide long-term immunity. Since the onset of the pandemic, SARS-CoV-2 neutralizing antibodies have been comprehensively investigated and critical information on their development, function, and potential use to prevent and treat COVID-19 have been revealed. With the emergence of SARS-CoV-2 immune escape variants, humoral immunity is being challenged, and a detailed understanding of neutralizing antibodies is essential to guide vaccine design strategies as well as antibody-mediated therapies. In this review, we summarize some of the key findings on SARS-CoV-2 neutralizing antibodies, with a focus on their clinical application.

Multiple Routes of Antibody-Dependent Enhancement of SARS-CoV-2 Infection

Antibody-dependent enhancement (ADE) of infection is generally known for many viruses. A potential risk of ADE in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has also been discussed since the beginning of the coronavirus disease 2019 (COVID-19) pandemic; however, clinical evidence of the presence of antibodies with ADE potential is limited. Here, we show that ADE antibodies are produced by SARS-CoV-2 infection and the ADE process can be mediated by at least two different host factors, Fcγ receptor (FcγR) and complement component C1q. Of 89 serum samples collected from acute or convalescent COVID-19 patients, 62.9% were found to be positive for SARS-CoV-2-specific IgG. FcγR- and/or C1q-mediated ADE were detected in 50% of the IgG-positive sera, whereas most of them showed neutralizing activity in the absence of FcγR and C1q. Importantly, ADE antibodies were found in 41.4% of the acute COVID-19 patients. Neutralizing activity was also detected in most of the IgG-positive sera, but it was counteracted by ADE in subneutralizing conditions in the presence of FcγR or C1q. Although the clinical importance of ADE needs to be further investigated with larger numbers of COVID-19 patient samples, our data suggest that SARS-CoV-2 utilizes multiple mechanisms of ADE. C1q-mediated ADE may particularly have a clinical impact since C1q is present at high concentrations in plasma and its receptors are ubiquitously expressed on the surfaces of many types of cells, including respiratory epithelial cells, which SARS-CoV-2 primarily infects.

IMPORTANCE Potential risks of antibody-dependent enhancement (ADE) in the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been discussed and the proposed mechanism mostly depends on the Fc gamma receptor (FcγR). However, since FcγRs are exclusively expressed on immune cells, which are not primary targets of SARS-CoV-2, the clinical importance of ADE of SARS-CoV-2 infection remains controversial. Our study demonstrates that SARS-CoV-2 infection induces antibodies that increase SARS-CoV-2 infection through another ADE mechanism in which complement component C1q mediates the enhancement. Although neutralizing activity was also detected in the serum samples, it was counteracted by ADE in the presence of FcγR or C1q. Considering the ubiquity of C1q and its cellular receptors, C1q-mediated ADE may more likely occur in respiratory epithelial cells, which SARS-CoV-2 primarily infects. Our data highlight the importance of careful monitoring of the antibody properties in COVID-19 convalescent and vaccinated individuals.

High-cited favorable studies for COVID-19 treatments ineffective in large trials

Objectives

Study Design and Setting

Results

Conclusion

Immunotherapy and CRISPR Cas Systems: Potential Cure of COVID-19?

The COVID-19 has plunged the world into a pandemic that affected millions. The continually emerging new variants of concern raise the question as to whether the existing vaccines will continue to provide sufficient protection for individuals from SARS-CoV-2 during natural infection. This narrative review aims to briefly outline various immunotherapeutic options and discuss the potential of clustered regularly interspaced short palindromic repeat (CRISPR Cas system technology against COVID-19 treatment as specific cure. As the development of vaccine, convalescent plasma, neutralizing antibodies are based on the understanding of human immune responses against SARS-CoV-2, boosting human body immune responses in case of SARS-CoV-2 infection, immunotherapeutics seem feasible as specific cure against COVID-19 if the present challenges are overcome. In cell based therapeutics, apart from the high costs, risks and side effects, there are technical problems such as the production of sufficient potent immune cells and antibodies under limited time to treat the COVID-19 patients in mild conditions prior to progression into a more severe case. The CRISPR Cas technology could be utilized to refine the specificity and safety of CAR-T cells, CAR-NK cells and neutralizing antibodies against SARS-CoV-2 during various stages of the COVID-19 disease progression in infected individuals. Moreover, CRISPR Cas technology are proposed in hypotheses to degrade the viral RNA in order to terminate the infection caused by SARS-CoV-2. Thus personalized cocktails of immunotherapeutics and CRISPR Cas systems against COVID-19 as a strategy might prevent further disease progression and circumvent immunity escape.

National Research Institute of Tuberculosis and Lung Disease (NRITLD) Protocol for the Treatment of Patients with COVID-19

: More than a year after the onset of the coronavirus disease pandemic in 2019, the disease remains a major global health issue. During this time, health organizations worldwide have tried to provide integrated treatment guidelines to control coronavirus disease 2019 (COVID-19) at different levels. However, due to the novel nature of the disease and the emergence of new variants, medical teams' updating medical information and drug prescribing guidelines should be given special attention. This version is an updated instruction of the National Research Institute of Tuberculosis and Lung Disease (NRITLD) in collaboration with a group of specialists from Masih Daneshvari Hospital in Tehran, Iran, which is provided to update the information of caring clinicians for the treatment and care of COVID-19 hospitalized patients.

Perplexing issues for convalescent immune plasma therapy in COVID-19

Convalescent immune plasma (CIP) therapy in coronavirus disease 2019 (COVID-19) is presently a trendy choice of treatment. On March 24, 2020, the United States Food and Drug Administration approved of CIP treatment for seriously ill COVID-19 patients as an emergency investigational new drug. The precise mechanisms of action for CIP in COVID-19 have not yet been undoubtedly recognized. However, earlier research demonstrated that the main mechanism of CIP such as in other viral infections is viral neutralization. Systematic reviews and meta-analyses of the CIP transfusion in severe infectious diseases have shown that CIP has some beneficial effects and it is a harmless process to cure infectious diseases early after symptom beginning. It is suggested that SARS-CoV-2 neutralizing antibody titers in CIP should be ideally higher than 1:320, but lower thresholds could also be useful. The suggested minimum dose for one individual is one unit (200 mL) of CIP. The second unit can be given 48 h succeeding the end of the transfusion of the first unit of CIP. Moreover, CIP can be applied up to a maximum of three units (600 mL). CIP could be administered in other systemic diseases, viral infections coincidentally associated with SARS-CoV-2 infection, as well as other therapeutic approaches for COVID-19. There are generally no serious adverse events described from CIP transfusion in these recipients. CIP may have a significant role as one of the therapeutic modalities for various viral infections when enough vaccines or other specific therapeutic agents are not on hand.

Convalescent plasma therapy in patients with severe COVID-19, A single-arm, retrospective study

Convalescent plasma (CP) therapy has been suggested as a treatment for emerging viral diseases. Moreover, many studies have been conducted to evaluate the efficacy of COVID-19 CP therapy, with some of them indicating that CP may be a promising treatment for the disease. However, the evidence for CP therapy's effectiveness in severe COVID-19 cases is limited. So, this study aimed to assess the probable effects of CP therapy in patients diagnosed with severe COVID-19. The study was designed as a single-arm, retrospective cohort of patients with severe COVID. Demographic data, laboratory test reports, and convalescent plasma transfusion doses were collected from medical records for patients before and after convalescent plasma transfusion. The clinical outcomes were hospital discharge and death. Also, laboratory parameters considered secondary outcomes.

After CP therapy, some symptoms improved, especially in patients under 55 years old, as follows. Respiratory function was significantly enhanced after convalescent plasma transfusion, and the inflammatory biomarkers' values decreased significantly (p < 0.05). Moreover, the estimated median of partial thromboplastin time (PTT) and Prothrombin time (PT) in patients did not change after CP therapy (p > 0.05). Regarding COVID-19 mortality, a strong association was found between older ages and death (p < 0.001). Also, CP transfusion in the early days of admission was effective in treatment outcomes (p = 0.023). Other characteristics, including sex, blood group, number of CP transfusions, and preexisting conditions, did not significantly correlate with mortality.

In conclusion, this study demonstrates the effectiveness of CP therapy in patients under the age of 55. Despite some improvement, we could not say that they were entirely due to the CP treatment. More extensive randomized clinical trials that cover different stages of the disease are needed.