Efficacy of High-Dose Polyclonal Intravenous Immunoglobulin in COVID-19: A Systematic Review

Intravenous immunoglobulin for treatment of hospitalized COVID-19 patients: an evidence mapping and meta-analysis

BACKGROUND

The clinical efficacy and safety of intravenous immunoglobulin (IVIg) treatment for COVID-19 remain controversial. This study aimed to map the current status and gaps of available evidence, and conduct a meta-analysis to further investigate the benefit of IVIg in COVID-19 patients.

METHODS

Electronic databases were searched for systematic reviews/meta-analyses (SR/MAs), primary studies with control groups, reporting on the use of IVIg in patients with COVID-19. A random-effects meta-analysis with subgroup analyses regarding study design and patient disease severity was performed. Our outcomes of interest determined by the evidence mapping, were mortality, length of hospitalization (days), length of intensive care unit (ICU) stay (days), number of patients requiring mechanical ventilation, and adverse events.

RESULTS

We included 34 studies (12 SR/MAs, 8 prospective and 14 retrospective studies). A total of 5571 hospitalized patients were involved in 22 primary studies. Random-effects meta-analyses of very low to moderate evidence showed that there was little or no difference between IVIg and standard care or placebo in reducing mortality (relative risk [RR] 0.91; 95% CI 0.78-1.06; risk difference [RD] 3.3% fewer), length of hospital (mean difference [MD] 0.37; 95% CI - 2.56, 3.31) and ICU (MD 0.36; 95% CI - 0.81, 1.53) stays, mechanical ventilation use (RR 0.92; 95% CI 0.68-1.24; RD 2.8% fewer), and adverse events (RR 0.98; 95% CI 0.84-1.14; RD 0.5% fewer) of patients with COVID-19. Sensitivity analysis using a fixed-effects model indicated that IVIg may reduce mortality (RR 0.76; 95% CI 0.60-0.97), and increase length of hospital stay (MD 0.68; 95% CI 0.09-1.28).

CONCLUSION

Very low to moderate certainty of evidence indicated IVIg may not improve the clinical outcomes of hospitalized patients with COVID-19. Given the discrepancy between the random- and fixed-effects model results, further large-scale and well-designed RCTs are warranted.

What we learned from steroid therapy in the COVID-19 pandemic

Background

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a pandemic named coronavirus disease 2019 (COVID-19) that has become the greatest worldwide public health threat. Although different treatment recommendations are offered for COVID-19 infection, steroid treatment remains important.

Aim

We aimed to demonstrate the effect of pulse steroid therapy (PST) on inflammatory markers and patient outcomes in moderate/severe COVID-19 pneumonia.

Materials and Methods

We retrospectively analyzed the patients 18 years and older hospitalized in our hospital's COVID-19 clinics between April 1, 2020, to June 30, 2020, and July 1, 2021, to November 30, 2021. Patients in the moderate/severe COVID-19 pneumonia category, according to the World Health Organization COVID-19 guidelines, were included in the study. The demographic characteristics of the patients, treatments, inflammatory markers, and patient outcomes (need for intensive care, length of hospital stay, high-flow nasal oxygen (HFNO) requirement, mechanical ventilation (MV), and mortality rates) were recorded and analyzed.

Results

Patients who received PST had more advanced age (P < 0.01), more comorbidities (P < 0.001), and more HFNO need (P < 001) compared with the patients who did not receive PST. There was no statistically significant difference between clinical outcomes: the need for intensive care, length of hospital stay, need for MV, and mortality rates (P = 0.54, P = 0.3, P = 0.14, and P = 0.09, respectively). When we evaluated the unvaccinated patients, there was a statistically significant difference in the MV need and mortality rates between those who received PST and those who did not (P = 0.017, P = 0.014, respectively).

Conclusion

It was observed that PST provided similar mortality, ICU, and MV requirements in patients with older age and comorbidities. Lower MV requirements and mortality were observed in the unvaccinated group receiving PST compared with the unvaccinated group not receiving steroids. PST is still promising in COVID-19 infection, and more studies are needed for standard doses and applications.

Hyperimmune Globulins for the Management of Infectious Diseases

This review is focused on the use of hyperimmune globulin therapy to treat some infectious diseases of viral or bacterial origin. Despite the introduction of antibiotics and vaccines, plasma immunoglobulin therapy from whole blood donation can still play a key role. These treatments provide passive transfer of high-titer antibodies that either reduces the risk or the severity of the infection and offer immediate but short-term protection against specific diseases. Antibody preparations derived from immunized human donors are commonly used for the prophylaxis and treatment of rabies, hepatitis A and B viruses, varicella-zoster virus, and pneumonia caused by respiratory syncytial virus, Clostridium tetani, Clostridium botulinum. The use of hyperimmune globulin therapy is a promising challenge, especially for the treatment of emerging viral infections for which there are no specific therapies or licensed vaccines.

Intravenous immunoglobulins (IVIG) in severe/critical COVID-19 adult patients

The coronavirus disease 2019 (COVID-19) pandemic has become a huge obstacle to the health system due to the high rate of contagion. It is postulated that intravenous immunoglobulins (IVIG) can lower the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related inflammation and prevent the development of acute respiratory distress syndrome (ARDS). The main advantages of IVIG treatment might be targeting cytokine storm in severe and critical COVID-19 by influences on complement, innate immune cells, effector T-cells, and Tregs. Randomized clinical trials (RCTs) and non-RCTs evaluating the safety and efficacy of IVIG in patients with severe/critical COVID-19 were performed. It seems that early administration of high-dose IVIG (in the acceleration phase of the disease) in severe or especially critical COVID-19 may be an effective therapeutic option, but there are no strong data to use it routinely. The results regarding mortality reduction are inconclusive. Additionally, IVIG treatment carries a risk of complications that should be considered when initiating treatment. However, given the COVID-19 mortality rate and limited therapeutic options, the use of IVIG is worth considering. This review summarizes the development and highlights recent advances in treatment with IVIG of severe/critically ill COVID-19 patients.

Benefits of high-dose intravenous immunoglobulin on mortality in patients with severe COVID-19: An updated systematic review and meta-analysis

Background

The clinical benefits of high-dose intravenous immunoglobulin (IVIg) in treating COVID-19 remained controversial.

Methods

We systematically searched databases up to February 17, 2022, for studies examining the efficacy of IVIg compared to routine care. Meta-analyses were conducted using the random-effects model. Subgroup analysis, meta-regression, and trial series analysis w ere performed to explore heterogeneity and statistical significance.

Results

A total of 4,711 hospitalized COVID-19 patients (1,925 IVIg treated and 2786 control) were collected from 17 studies, including five randomized controlled trials (RCTs) and 12 cohort studies. The application of IVIg was not associated with all-cause mortality (RR= 0.89 [0.63, 1.26], P= 0.53; I² = 75%), the length of hospital stays (MD= 0.29 [-3.40, 6.44] days, P= 0.88; I2 = 96%), the needs for mechanical ventilation (RR= 0.93 ([0.73, 1.19], P= 0.31; I2 = 56%), or the incidence of adverse events (RR= 1.15 [0.99, 1.33], P= 0.06; I2 = 20%). Subgroup analyses showed that overall mortality among patients with severe COVID-19 was reduced in the high-dose IVIg subgroup (RR= 0.33 [0.13, 0.86], P= 0.02, I² = 68%; very low certainty).

Conclusions

Results of this study suggest that severe hospitalized COVID-19 patients treated with high-dose IVIg would have a lower risk of death than patients with routine care.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021231040, identifier CRD42021231040.

Pharmacological therapies and drug development targeting SARS-CoV-2 infection

The development of therapies for SARS-CoV-2 infection, based on virus biology and pathology, and of large- and small-scale randomized controlled trials, have brought forward several antiviral and immunomodulatory drugs targeting the disease severity. Casirivimab/Imdevimab monoclonal antibodies and convalescent plasma to prevent virus entry, Remdesivir, Molnupiravir, and Paxlovid nucleotide analogs to prevent viral replication, a variety of repurposed JAK-STAT signaling pathway inhibitors, corticosteroids, and recombinant agonists/antagonists of cytokine and interferons have been found to provide clinical benefits in terms of mortality and hospitalization. However, current treatment options face multiple clinical needs, and therefore, in this review, we provide an update on the challenges of the existing therapeutics and highlight drug development strategies for COVID-19 therapy, based on ongoing clinical trials, meta-analyses, and clinical case reports.

Intravenous immunoglobulin (IVIg) therapy in hospitalised adult COVID-19 patients: A systematic review and meta-analysis

Intravenous immunoglobulin (IVIg) therapy has been suggested as a potential treatment option for hospitalised COVID-19 patients. The aim of this systematic review and meta-analysis was to investigate the potential impact of IVIg on mortality and length of hospitalisation in adult COVID-19 patients. PubMed, Scopus, Web of Science and medRxiv were searched in the week of 20.12.2021 for English language, prospective trials, and retrospective studies with control groups, reporting on the use of intravenous immunoglobulin therapy in adult hospitalised COVID-19 patients. Exclusion criteria were: studies evaluating the use of IVIg in paediatric COVID-19 cases, trials using convalescent anti-SARS-CoV-2 plasma or immunoglobulins derived from convalescent anti-SARS-CoV-2 plasma. A random effects meta-analysis with subgroup analyses regarding study design and patient disease severity according to WHO criteria was also performed. A total of 13 studies were included, of which 6 were prospective, on a total of 2313 (IVIg = 1104, control = 1209) patient outcomes. Meta-analysis results indicated that IVIg therapy had no statistically significant effect on mortality (RR 0.91 [0.59; 1.39], p = 0.65, I²  = 69% [46%; 83%]) or length of hospital stay (MD 0.51 [-2.80; 3.81], p = 0.76, I²  = 96% [94%; 98%]). Subgroup analyses indicated no statistically significant impact on either outcome, but prospective studies' results suggested that IVIg may increase the length of hospitalisation in the severe COVID-19 patient group (MD 2.66 [1.43; 3.90], p < 0.01, I²  = 0% [0%; >90%]). The results of this meta-analysis do not support use of IVIg in hospitalised adult COVID-19 patients.

Immune-based therapeutic approaches in COVID-19

Coronavirus disease 2019 (COVID-19) is a viral disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a member of the Coronaviridae family. On March 11, 2020 the World Health Organization (WHO) has named the newly emerged rapidly-spreading epidemic as a pandemic. Besides the risk-reduction measures such as physical and social distancing and vaccination, a wide range of treatment modalities have been developed; aiming to fight the disease. The immune system is known as a double-edged sword in COVID-19 pathogenesis, with respect to its role in eliminating the pathogen and in inducing complications such as cytokine storm syndrome. Hence, immune-based therapeutic approaches have become an interesting field of COVID-19 research, including corticosteroids, intravenous immunoglobulins (IVIG), interferon therapy, and more COVID-19-specific approaches such as anti-SARS-CoV-2-monoclonal antibodies. Herein, we did a comprehensive review on immune-based therapeutic approaches for COVID-19. DATA AVAILABILITY STATEMENT: Not applicable.

Passive Immunotherapy Against SARS-CoV-2: From Plasma-Based Therapy to Single Potent Antibodies in the Race to Stay Ahead of the Variants

The COVID-19 pandemic is now approaching 2 years old, with more than 440 million people infected and nearly six million dead worldwide, making it the most significant pandemic since the 1918 influenza pandemic. The severity and significance of SARS-CoV-2 was recognized immediately upon discovery, leading to innumerable companies and institutes designing and generating vaccines and therapeutic antibodies literally as soon as recombinant SARS-CoV-2 spike protein sequence was available. Within months of the pandemic start, several antibodies had been generated, tested, and moved into clinical trials, including Eli Lilly's bamlanivimab and etesevimab, Regeneron's mixture of imdevimab and casirivimab, Vir's sotrovimab, Celltrion's regdanvimab, and Lilly's bebtelovimab. These antibodies all have now received at least Emergency Use Authorizations (EUAs) and some have received full approval in select countries. To date, more than three dozen antibodies or antibody combinations have been forwarded into clinical trials. These antibodies to SARS-CoV-2 all target the receptor-binding domain (RBD), with some blocking the ability of the RBD to bind human ACE2, while others bind core regions of the RBD to modulate spike stability or ability to fuse to host cell membranes. While these antibodies were being discovered and developed, new variants of SARS-CoV-2 have cropped up in real time, altering the antibody landscape on a moving basis. Over the past year, the search has widened to find antibodies capable of neutralizing the wide array of variants that have arisen, including Alpha, Beta, Gamma, Delta, and Omicron. The recent rise and dominance of the Omicron family of variants, including the rather disparate BA.1 and BA.2 variants, demonstrate the need to continue to find new approaches to neutralize the rapidly evolving SARS-CoV-2 virus. This review highlights both convalescent plasma- and polyclonal antibody-based approaches as well as the top approximately 50 antibodies to SARS-CoV-2, their epitopes, their ability to bind to SARS-CoV-2 variants, and how they are delivered. New approaches to antibody constructs, including single domain antibodies, bispecific antibodies, IgA- and IgM-based antibodies, and modified ACE2-Fc fusion proteins, are also described. Finally, antibodies being developed for palliative care of COVID-19 disease, including the ramifications of cytokine release syndrome (CRS) and acute respiratory distress syndrome (ARDS), are described.