A Neutralizing Monoclonal Antibody for Hospitalized Patients with Covid-19

Effectiveness of Regdanvimab Treatment in High-Risk COVID-19 Patients to Prevent Progression to Severe Disease

Objective

To evaluate clinical effectiveness of regdanvimab, a monoclonal antibody agent for treating coronavirus 2019 (COVID-19).

Methods

A retrospective cohort study was conducted at two general hospitals during the study period of December 2020 to May 2021. Mild COVID-19 patients with risk factors for disease progression admitted to the hospitals within seven days of symptom onset were enrolled and followed until discharge or referral. Multivariate analyses for disease progression were conducted in the total and propensity score (PS)-matched cohorts.

Results

A total of 778 mild COVID-19 patients were included and classified as the regdanvimab (n = 234) and supportive care (n = 544) groups. Significantly fewer patients required O₂ supplementation via nasal prong in the regdanvimab group (8.1%) than in the supportive care group (18.4%, P < 0.001). The decreased risk for O₂ support by regdanvimab treatment was noticed in the multivariate analysis of the total cohort (HR 0.570, 95% CI 0.343-0.946, P = 0.030), but it was not statistically significant in the PS-matched cohort (P = 0.057). Progression to severe disease was also significantly lower in the regdanvimab group (2.1%) than in the supportive care group (9.6%, P < 0.001). The significantly reduced risk for progression to severe disease by regdanvimab treatment was observed in the analysis of both the total cohort (HR 0.262, 95% CI 0.103-0.667, P = 0.005) and PS-matched cohort (HR 0.176, 95% CI 0.060-0.516, P = 0.002). Potential risk factors for progression were investigated in the supportive care group and SpO₂ < 97% and CRP elevation >1.5 mg/dL were common risk factors for O₂ support and progression to severe disease. Among the patients with any of these factors, regdanvimab treatment was associated with decreased risk for progression to severe disease with slightly lower HR (HR 0.202, 95% CI 0.062-0.657, P = 0.008) than that of the total cohort.

Conclusion

Regdanvimab treatment was associated with a decreased risk of progression to severe disease.

Therapeutic Options for Coronavirus Disease 2019 (COVID-19): Where Are We Now?

PURPOSE OF REVIEW

Rapidly evolving treatment paradigms of coronavirus disease 2019 (COVID-19) introduce challenges for clinicians to keep up with the pace of published literature and to critically appraise the voluminous data produced. This review summarizes the clinical evidence from key studies examining the place of therapy of recommended drugs and management strategies for COVID-19.

RECENT FINDINGS

The global magnitude and duration of the pandemic have resulted in a flurry of interventional treatment trials evaluating both novel and repurposed drugs targeting various aspects of the viral life cycle. Additionally, clinical observations have documented various stages or phases of COVID-19 and underscored the importance of timing for the efficacy of studied therapies. Since the start of the COVID-19 pandemic, many observational, retrospective, and randomized controlled studies have been conducted to guide management of COVID-19 using drug therapies and other management strategies. Large, randomized, or adaptive platform trials have proven the most informative to guide recommended treatments to-date. Antimicrobial stewardship programs can play a pivotal role in ensuring appropriate use of COVID-19 therapies based on evolving clinical data and limiting unnecessary antibiotics given low rates of co-infection.

SUMMARY

Given the rapidly evolving medical literature and treatment paradigms, it is recommended to reference continuously updated, curated guidelines from national and international sources. While the drugs and management strategies mentioned in this review represent the current state of recommendations, many therapies are still under investigation to further define optimal COVID-19 treatment.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11908-021-00769-8.

Passive immune therapies: another tool against COVID-19

Passive immune therapy consists of several different therapies, convalescent plasma, hyperimmune globulin, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing monoclonal antibodies. Although these treatments were not part of any pandemic planning prior to coronavirus disease 2019 (COVID-19), due to the absence of high-quality evidence demonstrating benefit in other severe respiratory infections, a large amount of research has now been performed to demonstrate their benefit or lack of benefit in different patient groups. This review summarizes the evidence up to July 2021 on their use and also when they should not be used or when additional data are required. Vaccination against SARS-CoV-2 is the most important method of preventing severe and fatal COVID-19 in people who have an intact immune system. Passive immune therapy should only be considered for patients at high risk of severe or fatal COVID-19. The only therapy that has received full regulatory approval is the casirivimab/imdevimab monoclonal cocktail; all other treatments are being used under emergency use authorizations. In Japan, it has been licensed to treat patients with mild to moderate COVID-19, and in the United Kingdom, it has also been licensed to prevent infection.

Efficacy and safety of current treatment interventions for patients with severe COVID-19 infection: A network meta-analysis of randomized controlled trials

This study aimed to assess the efficacy and safety of different medications available at present for severe coronavirus disease 2019 (COVID‐19) infection. We searched databases for randomized controlled trials (RCTs) published up to April 30, 2021, with Chinese or English language restriction, of medications recommended for patients (aged 18 years or older) with severe COVID‐19 infection. We extracted data on trials and patient characteristics, and the following primary outcomes: all‐cause mortality (ACM), and treatment‐emergent adverse events (TEAEs). We identified 1855 abstracts and of these included 15 RCTs comprising 3073 participants through database searches and other sources. In terms of efficacy, compared with the standard of care (SOC) group, no significant decrease in ACM was found in α‐lipoic acid, convalescent plasma (CP), azithromycin, tocilizumab, methylprednisolone, interferon beta, CP/SOC, high dosage sarilumab, low dosage sarilumab, remdesivir, lopinavir–ritonavir, auxora, and placebo group. Compared with placebo, we found that a significant decrease in ACM was only found in methylprednisolone (odds ratio [OR]: 0.16, 95% confidence interval [CI]: 0.03–0.75]. With respect to TEAEs, the CP group showed lower TEAEs than placebo (OR: 0.07, 95% CI: 0.01–0.58) or SOC (OR: 0.05, 95% CI: 0.01–0.42) group for the therapy of severe COVID‐19 patients. This study only demonstrated that methylprednisolone was superior to placebo in treating patients with severe COVID‐19 infection. Meanwhile, this further confirmed that the safety of other treatment interventions might be inferior to CP for the therapy of severe COVID‐19 patients.

We considered addressing direct and indirect comparisons of medications from the angle of severe COVID‐19 infection based on random controlled trials (RCTs)

We explored the difference of efficacy and safety of for the pharmaceutical interventions of severe COVID‐19 patients from different control conditions (i.e., placebo and SOC).

To date, the findings from this network meta‐analysis may represent much more comprehensive analysis for the medications of severe COVID‐19 infection.

MG1141A as a Highly Potent Monoclonal Neutralizing Antibody Against SARS-CoV-2 Variants

Since the coronavirus disease outbreak in 2019, several antibody therapeutics have been developed to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Antibody therapeutics are effective in neutralizing the virus and reducing hospitalization in patients with mild and moderate infections. These therapeutics target the spike protein of SARS-CoV-2; however, emerging mutations in this protein reduce their efficiency. In this study, we developed a universal SARS-CoV-2 neutralizing antibody. We generated a humanized monoclonal antibody, MG1141A, against the receptor-binding domain of the spike protein through traditional mouse immunization. We confirmed that MG1141A could effectively neutralize live viruses, with an EC₅₀ of 92 pM, and that it exhibited effective Fc-mediated functions. Additionally, it retained its neutralizing activity against the alpha (UK), beta (South Africa), and gamma (Brazil) variants of SARS-CoV-2. Taken together, our study contributes to the development of a novel antibody therapeutic approach, which can effectively combat emerging SARS-CoV-2 mutations.

ZRC3308 Monoclonal Antibody Cocktail Shows Protective Efficacy in Syrian Hamsters against SARS-CoV-2 Infection

We have developed a monoclonal antibody (mAb) cocktail (ZRC-3308) comprising of ZRC3308-A7 and ZRC3308-B10 in the ratio 1:1 for COVID-19 treatment. The mAbs were designed to have reduced immune effector functions and increased circulation half-life. mAbs showed good binding affinities to non-competing epitopes on RBD of SARS-CoV-2 spike protein and were found neutralizing SARS-CoV-2 variants B.1, B.1.1.7, B.1.351, B.1.617.2, and B.1.617.2 AY.1 in vitro. The mAb cocktail demonstrated effective prophylactic and therapeutic activity against SARS-CoV-2 infection in Syrian hamsters. The antibody cocktail appears to be a promising candidate for prophylactic use and for therapy in early COVID-19 cases that have not progressed to severe disease.

Is SARS-CoV-2 viral clearance in nasopharyngeal swabs an appropriate surrogate marker for clinical efficacy of neutralising antibody-based therapeutics?

Viral clearance is likely the best way to assess the efficacy of antibody-based therapies. Although antibodies can mediate a variety of effects that include modulation of inflammation, the demonstration of viral clearance provides an accessible and measurable parameter that can be used to evaluate efficacy and determine dosing. Therefore, it is important to ascertain the ability of monoclonal antibodies and convalescent plasma to effect viral clearance. For COVID-19, which is caused by the respiratory virus SARS-CoV-2, the most common assay to assess viral clearance is via a nasopharyngeal swab (NPS). However, assessment of antibody efficacy by sampling this site may be misleading because it may not be as accessible to serum antibodies as respiratory secretions or circulating blood. Adding to the complexity of assessing the efficacy of administered antibody, particularly in randomised controlled trials (RCTs) that enroled patients at different times after the onset of COVID-19 symptoms, viral clearance may also be mediated by endogenous antibody. In this article we critically review available data on viral clearance in RCTs, matched control studies, case series and case reports of antibody therapies in an attempt to identify variables that contribute to antibody efficacy and suggest optimal strategies for future studies.

Lessons learned 1 year after SARS-CoV-2 emergence leading to COVID-19 pandemic

Without modern medical management and vaccines, the severity of the Coronavirus Disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) might approach the magnitude of 1894-plague (12 million deaths) and 1918-A(H1N1) influenza (50 million deaths) pandemics. The COVID-19 pandemic was heralded by the 2003 SARS epidemic which led to the discovery of human and civet SARS-CoV-1, bat SARS-related-CoVs, Middle East respiratory syndrome (MERS)-related bat CoV HKU4 and HKU5, and other novel animal coronaviruses. The suspected animal-to-human jumping of 4 betacoronaviruses including the human coronaviruses OC43(1890), SARS-CoV-1(2003), MERS-CoV(2012), and SARS-CoV-2(2019) indicates their significant pandemic potential. The presence of a large reservoir of coronaviruses in bats and other wild mammals, culture of mixing and selling them in urban markets with suboptimal hygiene, habit of eating exotic mammals in highly populated areas, and the rapid and frequent air travels from these areas are perfect ingredients for brewing rapidly exploding epidemics. The possibility of emergence of a hypothetical SARS-CoV-3 or other novel viruses from animals or laboratories, and therefore needs for global preparedness should not be ignored. We reviewed representative publications on the epidemiology, virology, clinical manifestations, pathology, laboratory diagnostics, treatment, vaccination, and infection control of COVID-19 as of 20 January 2021, which is 1 year after person-to-person transmission of SARS-CoV-2 was announced. The difficulties of mass testing, labour-intensive contact tracing, importance of compliance to universal masking, low efficacy of antiviral treatment for severe disease, possibilities of vaccine or antiviral-resistant virus variants and SARS-CoV-2 becoming another common cold coronavirus are discussed.

Convalescent plasma for COVID-19: a meta-analysis, trial sequential analysis, and meta-regression

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibodies, particularly those preventing interaction between the viral spike receptor-binding domain and the host angiotensin-converting enzyme 2 receptor, may prevent viral entry into host cells and disease progression.

METHODS

We performed a systematic review, meta-analysis, trial sequential analysis (TSA), and meta-regression of RCTs to evaluate the benefit of convalescent plasma for COVID-19. The primary outcome was 28-30 day mortality. Secondary outcomes included need for mechanical ventilation and ICU admission. Data sources were PubMed, Embase, MedRxiv, and the Cochrane library on July 2, 2021.

RESULTS

We identified 17 RCTs that recruited 15 587 patients with 8027 (51.5%) allocated to receive convalescent plasma. Convalescent plasma use was not associated with a mortality benefit (24.7% vs 25.5%; odds ratio [OR]=0.94 [0.85-1.04]; P=0.23; I2=4%; TSA adjusted confidence interval [CI], 0.84-1.05), or reduction in need for mechanical ventilation (15.7% vs 15.4%; OR=1.01 [0.92-1.11]; P=0.82; I2=0%; TSA adjusted CI, 0.91-1.13), or ICU admission (22.4% vs 16.7%; OR=0.80 [0.21-3.09]; P=0.75; I2=63%; TSA adjusted CI, 0.0-196.05). Meta-regression did not reveal association with titre of convalescent plasma, timing of administration, or risk of death and treatment effect (P>0.05). Risk of bias was high in most studies.

CONCLUSIONS

In patients with COVID-19, there was no clear mortality benefit associated with convalescent plasma treatment. In patients with mild disease, convalescent plasma did not prevent either the need for mechanical ventilation or ICU admission.

CLINICAL TRIAL REGISTRATION

CRD42021234201 (PROSPERO).

Clinical Management of Adult Patients with COVID-19 Outside Intensive Care Units: Guidelines from the Italian Society of Anti-Infective Therapy (SITA) and the Italian Society of Pulmonology (SIP)

INTRODUCTION

The Italian Society of Anti-Infective Therapy (SITA) and the Italian Society of Pulmonology (SIP) constituted an expert panel for developing evidence-based guidance for the clinical management of adult patients with coronavirus disease 2019 (COVID-19) outside intensive care units.

METHODS

Ten systematic literature searches were performed to answer ten different key questions. The retrieved evidence was graded according to the Grading of Recommendations Assessment, Development, and Evaluation methodology (GRADE).

RESULTS AND CONCLUSION

The literature searches mostly assessed the available evidence on the management of COVID-19 patients in terms of antiviral, anticoagulant, anti-inflammatory, immunomodulatory, and continuous positive airway pressure (CPAP)/non-invasive ventilation (NIV) treatment. Most evidence was deemed as of low certainty, and in some cases, recommendations could not be developed according to the GRADE system (best practice recommendations were provided in similar situations). The use of neutralizing monoclonal antibodies may be considered for outpatients at risk of disease progression. For inpatients, favorable recommendations were provided for anticoagulant prophylaxis and systemic steroids administration, although with low certainty of evidence. Favorable recommendations, with very low/low certainty of evidence, were also provided for, in specific situations, remdesivir, alone or in combination with baricitinib, and tocilizumab. The presence of many best practice recommendations testified to the need for further investigations by means of randomized controlled trials, whenever possible, with some possible future research directions stemming from the results of the ten systematic reviews.

An overview of the preclinical discovery and development of bamlanivimab for the treatment of novel coronavirus infection (COVID-19): reasons for limited clinical use and lessons for the future

Introduction: In the COVID-19 pandemic emergency, research has been oriented toward the development of therapies that could cure critically ill patients and treatments that can reduce the number of hospitalized patients, in order to ease the pressure on health-care systems. Bamlanivimab, developed from human convalescent plasma, was the first monoclonal antibody to become available for emergency use in several countries. Expectations related to its use in COVID-19 patients as a single agent have been largely disregarded, especially against E484K-carrying SARS-CoV-2 variants.Areas covered: In this drug discovery case history, the development of the drug is described starting from the identification and selection of the antibody, from the pre-clinical and clinical trials up to the post-authorization phase.Expert opinion: Bamlanivimab has shown some efficacy in patients with mild to moderate COVID-19. Initially approved as a monotherapy, due to poor efficacy it is currently only usable in combination with etesevimab. Pharmacokinetic limitations and mainly the onset of SARS-CoV-2 variants are the main reasons for this limited clinical use. The use in preventing hospitalization also has ethical limits related to the sustainability of care, especially if, considering similar effectiveness, bamlanivimab is compared with convalescent plasma.

Pathogenesis and Treatment of Cytokine Storm Induced by Infectious Diseases

Cytokine storm is a phenomenon characterized by strong elevated circulating cytokines that most often occur after an overreactive immune system is activated by an acute systemic infection. A variety of cells participate in cytokine storm induction and progression, with profiles of cytokines released during cytokine storm varying from disease to disease. This review focuses on pathophysiological mechanisms underlying cytokine storm induction and progression induced by pathogenic invasive infectious diseases. Strategies for targeted treatment of various types of infection-induced cytokine storms are described from both host and pathogen perspectives. In summary, current studies indicate that cytokine storm-targeted therapies can effectively alleviate tissue damage while promoting the clearance of invading pathogens. Based on this premise, "multi-omics" immune system profiling should facilitate the development of more effective therapeutic strategies to alleviate cytokine storms caused by various diseases.

Implementation of platform trials in the COVID-19 pandemic: A rapid review

Motivation

Platform designs - master protocols that allow for new treatment arms to be added over time - have gained considerable attention in recent years. Between 2001 and 2019, 16 platform trials were initiated globally. The COVID-19 pandemic seems to have provided a new motivation for these designs. We conducted a rapid review to quantify and describe platform trials used in COVID-19.

Methods

We cross-referenced PubMed, ClinicalTrials.gov, and the Cytel COVID-19 Clinical Trials Tracker to identify platform trials, defined by their stated ability to add future arms.

Results

We identified 58 COVID-19 platform trials globally registered between January 2020 and May 2021. According to trial registries, 16 trials have added new therapies (median 3, IQR 4) and 11 have dropped arms (median 3, IQR 2.5). About 50% of trials publicly share their protocol, and 31 trials (53%) intend to share trial data. Forty-nine trials (84%) explicitly report adaptive features, and 21 trials (36%) state Bayesian methods.

Conclusions

During the pandemic, there has been a surge in the number of platform trials compared to historical use. While transparency in statistical methods and clarity of data sharing policies needs improvement, platform trials appear particularly well-suited for rapid evidence generation. Trials secured funding quickly and many succeeded in adding new therapies in a short time period, thus demonstrating the potential for these trial designs to be implemented beyond the pandemic. The evidence gathered here may provide ample insight to further inform operational, statistical, and regulatory aspects of future platform trial conduct.

The use of neutralizing monoclonal antibodies and risk of hospital admission and mortality in patients with COVID-19: a systematic review and meta-analysis of randomized trials

Aim

Several randomized trials have evaluated the effect of neutralizing monoclonal antibodies on the risk of hospital admission and risk of mortality in patients with COVID-19. We aimed to summarize the overall evidence in the form of a systematic review and meta-analysis.

Methods

A systematic literature search with no language restriction was performed in electronic databases and preprint repositories to identify eligible studies published up to 29 June 2021. The outcomes of interest were hospital admission and all-cause mortality. A random-effects model was used to estimate the pooled odds ratio (OR) for outcomes of interest with the use of neutralizing monoclonal antibodies relative to nonuse of neutralizing monoclonal antibodies, at 95% confidence intervals (CI).

Results

Our systematic literature search identified nine randomized controlled trials. Three trials had an overall low risk of bias, while four trials had some concerns in the overall risk of bias. The meta-analysis revealed no statistically significant difference in the odds of mortality (pooled OR = 0.69; 95% CI 0.33–1.47), but a statistically significant reduction in the odds of hospital admission (pooled OR = 0.29; 95% CI 0.21–0.42), with the administration of a neutralizing monoclonal antibody among patients with COVID-19, relative to non-administration of a neutralizing monoclonal antibody, at the current sample size.

Conclusion

The reduced risk of hospital admission with neutralizing monoclonal antibodies use suggests that the timing of neutralizing antibodies administration is key in preventing hospital admission and, ultimately, death. Future randomized trials should aim to determine if the clinical outcomes with neutralizing monoclonal antibodies differ based on serostatus.

Effect of famotidine on hospitalized patients with COVID-19: A systematic review and meta-analysis

Introduction

Famotidine is a competitive histamine H2-receptor antagonist most commonly used for gastric acid suppression but thought to have potential efficacy in treating patients with Coronavirus disease 2019 (COVID-19). The aims of this systematic review and meta-analysis are to summarize the current literature and report clinical outcomes on the use of famotidine for treatment of hospitalized patients with COVID-19.

Methods

Five databases were searched through February 12, 2021 to identify observational studies that reported on associations of famotidine use with outcomes in COVID-19. Meta-analysis was conducted for composite primary clinical outcome (e.g. rate of death, intubation, or intensive care unit admissions) and death separately, where either aggregate odds ratio (OR) or hazard ratio (HR) was calculated.

Results

Four studies, reporting on 46,435 total patients and 3,110 patients treated with famotidine, were included in this meta-analysis. There was no significant association between famotidine use and composite outcomes in patients with COVID-19: HR 0.63 (95% CI: 0.35, 1.16). Across the three studies that reported mortality separated from other endpoints, there was no association between famotidine use during hospitalization and risk of death—HR 0.67 (95% CI: 0.26, 1.73) and OR 0.79 (95% CI: 0.19, 3.34). Heterogeneity ranged from 83.69% to 88.07%.

Conclusion

Based on the existing observational studies, famotidine use is not associated with a reduced risk of mortality or combined outcome of mortality, intubation, and/or intensive care services in hospitalized individuals with COVID-19, though heterogeneity was high, and point estimates suggested a possible protective effect for the composite outcome that may not have been observed due to lack of power. Further randomized controlled trials (RCTs) may help determine the efficacy and safety of famotidine as a treatment for COVID-19 patients in various care settings of the disease.

Clinical trials with antiviral drugs against COVID-19: some progress and many shattered hopes

Vaccines and drugs are the cornerstones in the fight against the SARS-CoV-2 pandemic. While vaccines were a success story, the development of antiviral drugs against SARS-CoV-2 turned out to be difficult. For an accelerated use of antivirals in the clinic, most SARS-CoV-2 antivirals represented repurposed drugs. The present article summarizes the outcomes of clinical trials with antiviral drugs in COVID-19 patients. Many antiviral drugs failed to demonstrate beneficial effects or showed mixed results. One reason for the low success rate of clinical trials was shortcomings of antiviral tests in cell culture systems and another reason was the abundance of ill-coordinated and underpowered clinical trials. However, large pragmatic clinical trials particularly of the British RECOVERY trial series demonstrated that even under emergency situation drug trials can be conducted in a timely way such that the therapy of COVID-19 patients can be based on evidence basis instead on expert opinion or even worse on political pressure.

25-Hydroxycholesterol-Conjugated EK1 Peptide with Potent and Broad-Spectrum Inhibitory Activity against SARS-CoV-2, Its Variants of Concern, and Other Human Coronaviruses

The COVID-19 pandemic caused by SARS-CoV-2 infection poses a serious threat to global public health and the economy. The enzymatic product of cholesterol 25-hydroxylase (CH25H), 25-Hydroxycholesterol (25-HC), was reported to have potent anti-SARS-CoV-2 activity. Here, we found that the combination of 25-HC with EK1 peptide, a pan-coronavirus (CoV) fusion inhibitor, showed a synergistic antiviral activity. We then used the method of 25-HC modification to design and synthesize a series of 25-HC-modified peptides and found that a 25-HC-modified EK1 peptide (EK1P4HC) was highly effective against infections caused by SARS-CoV-2, its variants of concern (VOCs), and other human CoVs, such as HCoV-OC43 and HCoV-229E. EK1P4HC could protect newborn mice from lethal HCoV-OC43 infection, suggesting that conjugation of 25-HC with a peptide-based viral inhibitor was a feasible and universal strategy to improve its antiviral activity.

COVID-19 Advanced Care

The coronavirus disease 2019 (COVID-19) pandemic, related to the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a worldwide sudden and substantial burden in public health due to an enormous increase in hospitalizations for pneumonia with the multiorgan disease. Treatment for individuals with COVID-19 includes best practices for supportive management of acute hypoxic respiratory failure. Emerging data indicate that dexamethasone therapy reduces 28-day mortality in patients requiring supplemental oxygen compared with usual care, and ongoing trials are testing the efficacy of antiviral therapies, immune modulators and anticoagulants in the prevention of disease progression and complications, while monoclonal antibodies and hyperimmune globulin may provide additional preventive strategies. Consensus suggestions can standardize care, thereby improving outcomes and facilitating future research. This review discusses current evidence regarding the pharmacotherapy of COVID-19.

COVA1-18 neutralizing antibody protects against SARS-CoV-2 in three preclinical models

Effective treatments against Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) are urgently needed. Monoclonal antibodies have shown promising results in patients. Here, we evaluate the in vivo prophylactic and therapeutic effect of COVA1-18, a neutralizing antibody highly potent against the B.1.1.7 isolate. In both prophylactic and therapeutic settings, SARS-CoV-2 remains undetectable in the lungs of treated hACE2 mice. Therapeutic treatment also causes a reduction in viral loads in the lungs of Syrian hamsters. When administered at 10 mg kg-1 one day prior to a high dose SARS-CoV-2 challenge in cynomolgus macaques, COVA1-18 shows very strong antiviral activity in the upper respiratory compartments. Using a mathematical model, we estimate that COVA1-18 reduces viral infectivity by more than 95% in these compartments, preventing lymphopenia and extensive lung lesions. Our findings demonstrate that COVA1-18 has a strong antiviral activity in three preclinical models and could be a valuable candidate for further clinical evaluation.

Safety, Tolerability, Pharmacokinetics, and Immunogenicity of a Monoclonal Antibody (SCTA01) Targeting SARS-CoV-2 in Healthy Adults: a Randomized, Double-Blind, Placebo-Controlled, Phase I Study

SCTA01 is a novel monoclonal antibody with promising prophylactic and therapeutic potential for COVID-19. This study aimed to evaluate the safety, tolerability, pharmacokinetics (PK) and immunogenicity of SCTA01 in healthy adults. This was a randomized, double-blind, placebo-controlled, dose escalation phase I clinical trial. Healthy adults were randomly assigned to cohort 1 (n = 5; 3:2), cohort 2 (n = 8; 6:2), cohort 3, or cohort 4 (both n = 10; 8:2) to receive SCTA01 (5, 15, 30, and 50 mg/kg, respectively) versus placebo. All participants were followed up for clinical, laboratory, PK, and immunogenicity assessments for 84 days. The primary outcomes were the dose-limiting toxicity (DLT) and maximal tolerable dose (MTD), and the secondary outcomes included PK parameters, immunogenicity, and adverse events (AE). Of the 33 participants, 18 experienced treatment-related AEs; the frequency was 52.0% (13/25) in participants receiving SCTA01 and 62.5% (5/8) in those receiving placebo. All AEs were mild. There was no serious AE or death. No DLT was reported, and the MTD of SCTA01 was not reached. SCTA01 with a dose range of 5 to 50 mg/kg had nearly linear dose-proportional increases in Cmax and AUC parameters. An antidrug antibody response was detected in four (16.0%) participants receiving SCTA01, with low titers, between the baseline and day 28, but all became negative later. In conclusion, SCTA01 up to 50 mg/kg was safe and well-tolerated in healthy participants. Its PK parameters were nearly linear dose-proportional. (This study has been registered at ClinicalTrials.gov under identifier NCT04483375.).

Efficacy of COVID-19 Treatments: A Bayesian Network Meta-Analysis of Randomized Controlled Trials

Background: We provided a comprehensive evaluation of efficacy of available treatments for coronavirus disease 2019 (COVID-19).

Methods: We searched for candidate COVID-19 studies in WHO COVID-19 Global Research Database up to August 19, 2021. Randomized controlled trials for suspected or confirmed COVID-19 patients published on peer-reviewed journals were included, regardless of demographic characteristics. Outcome measures included mortality, mechanical ventilation, hospital discharge and viral clearance. Bayesian network meta-analysis with fixed effects was conducted to estimate the effect sizes using posterior means and 95% equal-tailed credible intervals (CrIs). Odds ratio (OR) was used as the summary measure for treatment effect. Bayesian hierarchical models were used to estimate effect sizes of treatments grouped by the treatment classifications.

Results: We identified 222 eligible studies with a total of 102,950 patients. Compared with the standard of care, imatinib, intravenous immunoglobulin and tocilizumab led to lower risk of death; baricitinib plus remdesivir, colchicine, dexamethasone, recombinant human granulocyte colony stimulating factor and tocilizumab indicated lower occurrence of mechanical ventilation; tofacitinib, sarilumab, remdesivir, tocilizumab and baricitinib plus remdesivir increased the hospital discharge rate; convalescent plasma, ivermectin, ivermectin plus doxycycline, hydroxychloroquine, nitazoxanide and proxalutamide resulted in better viral clearance. From the treatment class level, we found that the use of antineoplastic agents was associated with fewer mortality cases, immunostimulants could reduce the risk of mechanical ventilation and immunosuppressants led to higher discharge rates.

Conclusions: This network meta-analysis identified superiority of several COVID-19 treatments over the standard of care in terms of mortality, mechanical ventilation, hospital discharge and viral clearance. Tocilizumab showed its superiority compared with SOC on preventing severe outcomes such as death and mechanical ventilation as well as increasing the discharge rate, which might be an appropriate treatment for patients with severe or mild/moderate illness. We also found the clinical efficacy of antineoplastic agents, immunostimulants and immunosuppressants with respect to the endpoints of mortality, mechanical ventilation and discharge, which provides valuable information for the discovery of potential COVID-19 treatments.

Early Administration of Bamlanivimab in Combination with Etesevimab Increases the Benefits of COVID-19 Treatment: Real-World Experience from the Liguria Region

Monoclonal antibodies, such as bamlanivimab and etesevimab combination (BEC), have been proposed for patients with mild or moderate coronavirus disease 2019 (COVID-19). However, few studies have assessed the factors associated with the early administration of BEC or the impact of early BEC treatment on the clinical evolution of the patients. We conducted a retrospective cohort study of all adults with COVID-19 who received BEC at three institutions in the Liguria region. The primary endpoint was to investigate the clinical variables associated with early BEC infusion. Secondary endpoints were 30-day overall mortality and the composite endpoint of requirement of hospital admission or need for supplemental oxygen during the 30-day follow-up period. A total of 127 patients (median age 70 years; 56.7% males) received BEC. Of those, 93 (73.2%) received BEC within 5 days from symptoms onset (early BEC). Patients with a higher Charlson comorbidity index were more likely to receive early treatment (odds ratio (OR) 1.60, 95% confidence interval (CI) 1.04–2.45; p = 0.03) in contrast to those reporting fever at presentation (OR 0.26, 0.08–0.82; p = 0.02). Early BEC was associated with lower likelihood of hospital admission or need for supplemental oxygen (OR 0.19, 0.06–0.65; p = 0.008). Five patients who received early BEC died during the follow-up period, but only one of them due to COVID-19-related causes. Early bamlanivimab and etesevimab combination was more frequently administered to patients with a high Charlson comorbidity index. Despite this, early BEC was associated with a lower rate of hospital admission or need for any supplementary oxygen compared to late administration. These results suggest that efforts should focus on encouraging early BEC use in patients with mild–moderate COVID-19 at risk for complications.

Mortality risk factors of COVID-19 infection in kidney transplantation recipients: a systematic review and meta-analysis of cohorts and clinical registries

Kidney transplantation recipients (KTR) with coronavirus disease 2019 (COVID-19) are at higher risk of death than general population. However, mortality risk factors in KTR are still not clearly identified. Our objective was to systematically analyze published evidence for risk factors associated with mortality in COVID-19 KTR. Electronic databases were searched for eligible studies on 1 August 2021. All prospective and retrospective studies of COVID-19 in KTR were considered eligible without language restriction. Since data in case reports and series could potentially be subsets of larger studies, only studies with ≥ 50 patients were included. Random-effects model meta-analysis was used to calculate weighted mean difference (WMD) and pooled odds ratio (OR) of factors associated with mortality. From a total 1,137 articles retrieved, 13 were included in the systematic review and meta-analysis comprising 4,440 KTR. Compared with survivors, non-survivors were significantly older (WMD 10.5 years, 95% CI 9.3-11.8). KTR of deceased donor were at higher risk of death (OR 1.73, 95% CI 1.10-2.74). Comorbidities including diabetes mellitus, cardiovascular disease, and active cancer significantly increased mortality risk. KTR with dyspnea (OR 5.68, 95% CI 2.11-15.33) and pneumonia (OR 10.64, 95% CI 3.37-33.55) at presentation were at higher mortality risk, while diarrhea decreased the risk (OR 0.61, 95% CI 0.47-0.78). Acute kidney injury was associated with mortality (OR 3.24, 95% CI 1.36-7.70). Inflammatory markers were significantly higher in the non-survivors, including C-reactive protein, procalcitonin, and interleukine-6. A number of COVID-19 mortality risk factors were identified from KTR patient characteristics, presenting symptoms, and laboratory investigations. KTR with these risk factors should receive more intensive monitoring and early therapeutic interventions to optimize health outcomes.

Coronavirus disease 2019 in children

PURPOSE OF REVIEW

Over the course of the coronavirus disease 2019 (COVID-19) pandemic, it has become clear that the clinical features, epidemiology, and outcomes of COVID-19 are distinct in children relative to adults. In this review, we will present recent pediatric studies informing our current understanding of COVID-19 in children, and review pediatric considerations surrounding disease transmission, currently available therapies, and vaccination.

RECENT FINDINGS

Recent studies have shed light on the clinical epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in children, identifying a high prevalence of asymptomatic and mild infections, with severe COVID-19 infrequently reported. Several adult clinical trials have informed the use of remdesivir, anti-SARS-CoV-2 monoclonal antibodies, dexamethasone, and tocilizumab in the management of COVID-19. Associations between underlying comorbid medical conditions and severe outcomes, as well as transmission dynamics of SARS-CoV-2 in children, are complex and warrant further study. Finally, highly efficacious vaccines are available for adults and adolescents, with pediatric trials ongoing.

SUMMARY

Children generally fare well with acute COVID-19 infection, though critical illness is possible. Future research should focus on clarifying the role of children in SARS-CoV-2 transmission and optimal prevention strategies, particularly in the school setting, as well as evaluating pediatric vaccine candidates.

Neutralizing antibodies for the prevention and treatment of COVID-19

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) initiates the infection process by binding to the viral cellular receptor angiotensin-converting enzyme 2 through the receptor-binding domain (RBD) in the S1 subunit of the viral spike (S) protein. This event is followed by virus-cell membrane fusion mediated by the S2 subunit, which allows virus entry into the host cell. Therefore, the SARS-CoV-2 S protein is a key therapeutic target, and prevention and treatment of coronavirus disease 2019 (COVID-19) have focused on the development of neutralizing monoclonal antibodies (nAbs) that target this protein. In this review, we summarize the nAbs targeting SARS-CoV-2 proteins that have been developed to date, with a focus on the N-terminal domain and RBD of the S protein. We also describe the roles that binding affinity, neutralizing activity, and protection provided by these nAbs play in the prevention and treatment of COVID-19 and discuss the potential to improve nAb efficiency against multiple SARS-CoV-2 variants. This review provides important information for the development of effective nAbs with broad-spectrum activity against current and future SARS-CoV-2 strains.

Remdesivir treatment in hospitalized patients with COVID-19: a comparative analysis of in-hospital all-cause mortality in a large multi-center observational cohort

Background

Remdesivir (RDV) improved clinical outcomes among hospitalized patients with coronavirus disease 2019 (COVID-19) in randomized trials, but data from clinical practice are limited.

Methods

We examined survival outcomes for US patients hospitalized with COVID-19 between August and November 2020 and treated with RDV within 2 days of hospitalization vs those not receiving RDV during their hospitalization using the Premier Healthcare Database. Preferential within-hospital propensity score matching with replacement was used. Additionally, patients were also matched on baseline oxygenation level (no supplemental oxygen charges [NSO], low-flow oxygen [LFO], high-flow oxygen/noninvasive ventilation [HFO/NIV], and invasive mechanical ventilation/extracorporeal membrane oxygenation [IMV/ECMO]) and 2-month admission window and excluded if discharged within 3 days of admission (to exclude anticipated discharges/transfers within 72 hours, consistent with the Adaptive COVID-19 Treatment Trial [ACTT-1] study). Cox proportional hazards models were used to assess time to 14-/28-day mortality overall and for patients on NSO, LFO, HFO/NIV, and IMV/ECMO.

Results

A total of 28855 RDV patients were matched to 16687 unique non-RDV patients. Overall, 10.6% and 15.4% RDV patients died within 14 and 28 days, respectively, compared with 15.4% and 19.1% non-RDV patients. Overall, RDV was associated with a reduction in mortality at 14 days (hazard ratio [95% confidence interval]: 0.76 [0.70–0.83]) and 28 days (0.89 [0.82–0.96]). This mortality benefit was also seen for NSO, LFO, and IMV/ECMO at 14 days (NSO: 0.69 [0.57–0.83], LFO: 0.68 [0.80–0.77], IMV/ECMO: 0.70 [0.58–0.84]) and 28 days (NSO: 0.80 [0.68–0.94], LFO: 0.77 [0.68–0.86], IMV/ECMO: 0.81 [0.69–0.94]). Additionally, HFO/NIV RDV group had a lower risk of mortality at 14 days (0.81 [0.70–0.93]) but no statistical significance at 28 days.

Conclusions

RDV initiated upon hospital admission was associated with improved survival among patients with COVID-19. Our findings complement ACTT-1 and support RDV as a foundational treatment for hospitalized COVID-19 patients.

Update of the recommendations of the Sociedade Portuguesa de Cuidados Intensivos and the Infection and Sepsis Group for the approach to COVID-19 in Intensive Care Medicine

INTRODUCTION

The Sociedade Portuguesa de Cuidados Intensivos and the Infection and Sepsis Group have previously issued health service and management recommendations for critically ill patients with COVID-19. Due to the evolution of knowledge, the panel of experts was again convened to review the current evidence and issue updated recommendations.

METHODS

A national panel of experts who declared that they had no conflicts of interest regarding the development of the recommendations was assembled. Operational questions were developed based on the PICO methodology, and a rapid systematic review was conducted by consulting different bibliographic sources. The panel determined the direction and strength of the recommendations using two Delphi rounds, conducted in accordance with the principles of the GRADE system. A strong recommendation received the wording "is recommended", and a weak recommendation was written as "is suggested."

RESULTS

A total of 48 recommendations and 30 suggestions were issued, covering the following topics: diagnosis of SARS-CoV-2 infection, coinfection and superinfection; criteria for admission, cure and suspension of isolation; organization of services; personal protective equipment; and respiratory support and other specific therapies (antivirals, immunomodulators and anticoagulation).

CONCLUSION

These recommendations, specifically oriented to the Portuguese reality but that may also apply to Portuguese-speaking African countries and East Timor, aim to support health professionals in the management of critically ill patients with COVID-19. They will be continuously reviewed to reflect the progress of our understanding and the treatment of this pathology.

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

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

COVID-19 in Children: Clinical Manifestations and Pharmacologic Interventions Including Vaccine Trials

Children usually present with milder symptoms of COVID-19 as compared with adults. Supportive care alone is appropriate for most children with COVID-19. Antiviral therapy may be required for those with severe or critical diseases. Currently there has been a rapid development of vaccines globally to prevent COVID-19 and several vaccines are being evaluated in children and adolescents. Currently, only the Pfizer-BioNTech messenger RNA vaccine is approved for emergency authorization use in the pediatric population ages 16 years and older.

Azithromycin versus standard care in patients with mild-to-moderate COVID-19 (ATOMIC2): an open-label, randomised trial

BACKGROUND

The antibacterial, anti-inflammatory, and antiviral properties of azithromycin suggest therapeutic potential against COVID-19. Randomised data in mild-to-moderate disease are not available. We assessed whether azithromycin is effective in reducing hospital admission in patients with mild-to-moderate COVID-19.

METHODS

This prospective, open-label, randomised superiority trial was done at 19 hospitals in the UK. We enrolled adults aged at least 18 years presenting to hospitals with clinically diagnosed, highly probable or confirmed COVID-19 infection, with fewer than 14 days of symptoms, who were considered suitable for initial ambulatory management. Patients were randomly assigned (1:1) to azithromycin (500 mg once daily orally for 14 days) plus standard care or to standard care alone. The primary outcome was death or hospital admission from any cause over the 28 days from randomisation. The primary and safety outcomes were assessed according to the intention-to-treat principle. This trial is registered at ClinicalTrials.gov (NCT04381962) and recruitment is closed.

FINDINGS

298 participants were enrolled from June 3, 2020, to Jan 29, 2021. Three participants withdrew consent and requested removal of all data, and three further participants withdrew consent after randomisation, thus, the primary outcome was assessed in 292 participants (145 in the azithromycin group and 147 in the standard care group). The mean age of the participants was 45·9 years (SD 14·9). 15 (10%) participants in the azithromycin group and 17 (12%) in the standard care group were admitted to hospital or died during the study (adjusted OR 0·91 [95% CI 0·43-1·92], p=0·80). No serious adverse events were reported.

INTERPRETATION

In patients with mild-to-moderate COVID-19 managed without hospital admission, adding azithromycin to standard care treatment did not reduce the risk of subsequent hospital admission or death. Our findings do not support the use of azithromycin in patients with mild-to-moderate COVID-19.

FUNDING

National Institute for Health Research Oxford Biomedical Research Centre, University of Oxford and Pfizer.

Immunomodulatory therapies for the treatment of SARS-CoV-2 infection: an update of the systematic literature review to inform EULAR points to consider

OBJECTIVE

To update the EULAR 2020 systematic literature review (SLR) on efficacy and safety of immunomodulatory agents in SARS-CoV-2 infection.

METHODS

As part of a EULAR taskforce, a systematic literature search update was conducted from 11 December 2020 to 14 July 2021. Two reviewers independently identified eligible studies and extracted data on efficacy and safety of immunomodulatory agents used therapeutically in SARS-CoV-2 infection at any stage of disease. The risk of bias (RoB) was assessed with validated tools.

RESULTS

Of the 26 959 records, 520 articles were eligible for inclusion. Studies were mainly at high or unclear RoB. New randomised controlled trials (RCTs) on tocilizumab clarified its benefit in patients with severe and critical COVID-19, mainly if associated with glucocorticoids. There are emergent data on the usefulness of baricitinib and tofacitinib in severe COVID-19. Other therapeutic strategies such as the use of convalescent plasma and anti-SARS-CoV-2 monoclonal antibodies showed efficacy in subjects not mounting normal anti-SARS-CoV-2 antibody responses.

CONCLUSION

This new SLR confirms that some immunomodulators (tocilizumab and JAK inhibitors) have a role for treating severe and critical COVID-19. Although better evidence is available compared with the previous SLR, the need of RCT with combination therapy (glucocorticoids+anti-cytokines) versus monotherapy with glucocorticoids still remains alongside the need for standardisation of inclusion criteria and outcomes to ultimately improve the care and prognosis of affected people. This SLR informed the 2021 update of the EULAR points to consider on the use of immunomodulatory therapies in COVID-19.

Severe Acute Respiratory Syndrome Coronavirus-2 Infection and Autoimmunity 1 Year Later: The Era of Vaccines

Impressive efforts have been made by researchers worldwide in the development of target vaccines against the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and in improving the management of immunomodulating agents. Currently, different vaccine formulations, such as viral vector, mRNA, and protein-based, almost all directed toward the spike protein that includes the domain for receptor binding, have been approved. Although data are not conclusive, patients affected by autoimmune rheumatic diseases (ARDs) seem to have a slightly higher disease prevalence, risk of hospitalization, and death from coronavirus disease-2019 (COVID-19) than the general population. Therefore, ARD patients, under immunosuppressive agents, have been included among the priority target groups for vaccine administration. However, specific cautions are needed to optimize vaccine safety and effectiveness in these patients, such as modification in some of the ongoing immunosuppressive therapies and the preferential use of mRNA other than vector-based vaccines. Immunomodulating agents can be a therapeutic opportunity for the management of COVID-19 patients; however, their clinical impact depends on how they are handled. To place in therapy immunomodulating agents in the correct window of opportunity throughout the identification of surrogate markers of disease progression and host immune response is mandatory to optimize patient's outcome.

Early Experience With Neutralizing Monoclonal Antibody Therapy for COVID-19: Retrospective Cohort Survival Analysis and Descriptive Study

Background

Neutralizing monoclonal antibody (MAB) therapies may benefit patients with mild to moderate COVID-19 at high risk for progressing to severe COVID-19 or hospitalization. Studies documenting approaches to deliver MAB infusions and demonstrating their efficacy are lacking.

Objective

We describe our experience and the outcomes of almost 3000 patients who received MAB infusion therapy at Northwell Health, a large integrated health care system in New York.

Methods

This is a descriptive study of adult patients who received MAB therapy between November 20, 2020, to January 31, 2021, and a retrospective cohort survival analysis comparing patients who received MAB therapy prior to admission versus those who did not. A multivariable Cox model with inverse probability weighting according to the propensity score including covariates (sociodemographic, comorbidities, and presenting vital signs) was used. The primary outcome was in-hospital mortality; additional evaluations included emergency department use and hospitalization within 28 days of a positive COVID-19 test for patients who received MAB therapy.

Results

During the study period, 2818 adult patients received MAB infusion. Following therapy and within 28 days of a COVID-19 test, 123 (4.4%) patients presented to the emergency department and were released, and 145 (5.1%) patients were hospitalized. These 145 patients were compared with 200 controls who were eligible for but did not receive MAB therapy and were hospitalized. In the MAB group, 16 (11%) patients met the primary outcome of in-hospital mortality, versus 21 (10.5%) in the control group. In an unadjusted Cox model, the hazard ratio (HR) for time to in-hospital mortality for the MAB group was 1.38 (95% CI 0.696-2.719). Models adjusting for demographics (HR 1.1, 95% CI 0.53-2.23), demographics and Charlson Comorbidity Index (HR 1.22, 95% CI 0.573-2.59), and with inverse probability weighting according to propensity scores (HR 1.19, 95% CI 0.619-2.29) did not demonstrate significance. The hospitalization rate was 4.4% for patients who received MAB therapy within 0 to 4 days, 5% within 5 to 7 days, and 6.1% in ≥8 days of symptom onset (P=.15).

Conclusions

Establishing the capability to provide neutralizing MAB infusion therapy requires substantial planning and coordination. Although this therapy may be an important treatment option for early mild to moderate COVID-19 in patients who are at high risk, further investigations are needed to define the optimal timing of MAB treatment to reduce hospitalization and mortality.

Broadly-Neutralizing Antibodies Against Emerging SARS-CoV-2 Variants

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have become a major concern in the containment of current pandemic. The variants, including B.1.1.7 (Alpha), B.1.351 (Beta), P1 (Gamma) and B.1.617.2 (Delta) have shown reduced sensitivity to monoclonal antibodies, plasma and/or sera obtained from convalescent patients and vaccinated individuals. Development of potent therapeutic monoclonal antibodies (mAbs) with broad neutralizing breadth have become a priority for alleviating the devastating effects of this pandemic. Here, we review some of the most promising broadly neutralizing antibodies obtained from plasma of patients that recovered from early variants of SARS-CoV-2 that may be effective against emerging new variants of the virus. This review summarizes several mAbs, that have been discovered to cross-neutralize across Sarbecoviruses and SARS-CoV-2 escape mutants. Understanding the characteristics that confer this broad and cross-neutralization functions of these mAbs would inform on the development of therapeutic antibodies and guide the discovery of second-generation vaccines.

Do we need bamlanivimab? Is etesevimab a key to treating Covid-19?

Introduction

Treatments for subjects with Covid-19 are required. One approach is neutralizing monoclonal antibodies. Bamlanivimab and etesevimab are monoclonal antibodies to SARS-CoV-2.

Areas Covered

This evaluation is of the phase 3 BLAZE-1 clinical trial, which was of bamlanivimab plus etesevimab in adult ambulatory participants with a risk factor for, and mild to moderate, Covid-19 illness. The primary outcome was Covid 19 related hospitalization of ≥ 24 hours or death from any cause by day 29, and this occurred in 2.1% subjects in the bamlanivimab/etesevimab group, compared to 7.0% in the placebo group.

Expert Opinion

In the pandemic, the attempts by the FDA to shorten approval processes for medicines and by journals to make information available in a timely manner are admirable. However, these shortened processes made negotiating the details of BLAZE-1 and producing accurate and critical appraisals difficult. It seems to me that if there are any benefits of bamlanivimab alone in Covid-19, they are not clear-cut. Bamlanivimab has limited effects against the beta and gamma variants and is not effective against the delta variant. Thus, the benefits of bamlanivimab/etesevimab in the phase 3 of the BLAZE-1 may be solely due to etesevimab, and this needs to be tested.

An ultrapotent pan-β-coronavirus lineage B (β-CoV-B) neutralizing antibody locks the receptor-binding domain in closed conformation by targeting its conserved epitope

New threats posed by the emerging circulating variants of SARS-CoV-2 highlight the need to find conserved neutralizing epitopes for therapeutic antibodies and efficient vaccine design. Here, we identified a receptor-binding domain (RBD)-binding antibody, XG014, which potently neutralizes β-coronavirus lineage B (β-CoV-B), including SARS-CoV-2, its circulating variants, SARS-CoV and bat SARSr-CoV WIV1. Interestingly, antibody family members competing with XG014 binding show reduced levels of cross-reactivity and induce antibody-dependent SARS-CoV-2 spike (S) protein-mediated cell-cell fusion, suggesting a unique mode of recognition by XG014. Structural analyses reveal that XG014 recognizes a conserved epitope outside the ACE2 binding site and completely locks RBD in the non-functional "down" conformation, while its family member XG005 directly competes with ACE2 binding and position the RBD "up". Single administration of XG014 is effective in protection against and therapy of SARS-CoV-2 infection in vivo. Our findings suggest the potential to develop XG014 as pan-β-CoV-B therapeutics and the importance of the XG014 conserved antigenic epitope for designing broadly protective vaccines against β-CoV-B and newly emerging SARS-CoV-2 variants of concern.

Pharmacology and Adverse Events of Emergency-Use Authorized Medication in Moderate to Severe COVID-19

Some effective drugs have been approved or issued an Emergency Use Authorization for the treatment of COVID-19 in hospitalized patients, but post-market surveillance is warranted to monitor adverse events. We reviewed clinical trials and case reports in patients with moderate-to-severe COVID-19 infection who received remdesivir, baricitinib, tocilizumab, or sarilumab. The drug-specific pharmacokinetics, toxicity, and drug interactions are summarized in this study. Remdesivir and baricitinib are small-molecule drugs that are mainly metabolized by the kidneys, while tocilizumab and sarilumab are monoclonal antibody drugs with metabolic pathways that are currently not fully understood. The most common adverse events of these drugs are alterations in liver function, but serious adverse events have rarely been attributed to them. Only a few studies have reported that remdesivir might be cardiotoxic and that baricitinib might cause thromboembolism. Biological agents such as baricitinib, tocilizumab, and sarilumab could inhibit the pathway of inflammatory processes, leading to immune dysregulation, so the risk of secondary infection should be assessed before prescribing. Further recognition of the pathogenic mechanism and risk factors of adverse events is essential for optimizing treatment strategies.

Combination therapies for COVID-19: An overview of the clinical trials landscape

The COVID-19 pandemic has driven an unprecedented level of global activity in drug discovery and clinical development for effective therapeutics targeting the coronavirus disease. There are currently 744 therapeutics being tested in 2879 clinical trials globally. Almost 90% of these clinical trials are focused on monotherapies. Combination therapies are the mainstay of antiviral therapeutics to increase the potency of the individual compounds and to combat the rapid evolution of resistance, although combination therapies have inherently complex clinical and regulatory development challenges. Increased understanding of the SARS-CoV-2 lifecycle and COVID-19 pathology provides a scientific rationale for evaluating the effectiveness of different combinations. In this paper, we provide an overview of the current clinical trial landscape for combination therapeutics targeting COVID-19 through weekly scanning of national and international clinical trial registries. Our analysis delves specifically into dual combination therapies in what can be defined as "pivotal clinical trials" (active, randomised, controlled and at least phase II), with a focus on new and repurposed therapeutic candidates that have shown positive signals and/or been granted authorisation for emergency use based on positive efficacy and safety data.

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

OBJECTIVE

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

DESIGN

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

DATA SOURCES

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

STUDY SELECTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

SYSTEMATIC REVIEW REGISTRATION

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

FUNDING

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

READERS' NOTE

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

Lack of efficacy of mono-mode of action therapeutics in COVID-19 therapy - How the lack of predictive power of preclinical cell and animal studies leads developments astray

The diverse experiences regarding the failure of tested drugs in the fight against COVID‐19 made it clear that one should at least question the requirement to apply classical preclinical development strategies that demand cell and animal efficacy models to be tested before going into clinical trials. Most animals are not susceptible to infection with SARS‐CoV‐2, and so this led to one‐sided virus replication experiments in cells and the use of animal models that have little in common with the complex pathogenesis of COVID‐19 in humans. Therefore, non‐clinical development strategies were designed to meet regulatory requirements, but they did not truly reflect the situation in the clinic. This has led the search for effective agents astray in many cases. As proof of this statement, we now bring together the results of such required preclinical experiments and compare with the results in clinical trials. Two clear conclusions that can be drawn from the experience to date: The required preclinical models are unsuitable for the development of innovative treatments medical devices in the case of COVID‐19 and mono‐action strategies (e.g. direct antivirals) are of very little or no benefit to patients under randomized,blinded conditions. Our hypothesis is that the complex situation of COVID‐19 may benefit from multi‐mode drugs. Here, the molecular class of aptamers could be a solution.

Therapeutic efficacy of an oral nucleoside analog of remdesivir against SARS-CoV-2 pathogenesis in mice

The COVID-19 pandemic remains uncontrolled despite the rapid rollout of safe and effective SARS-CoV-2 vaccines, underscoring the need to develop highly effective antivirals. In the setting of waning immunity from infection and vaccination, breakthrough infections are becoming increasingly common and treatment options remain limited. Additionally, the emergence of SARS-CoV-2 variants of concern with their potential to escape therapeutic monoclonal antibodies emphasizes the need to develop second-generation oral antivirals targeting highly conserved viral proteins that can be rapidly deployed to outpatients. Here, we demonstrate the in vitro antiviral activity and in vivo therapeutic efficacy of GS-621763, an orally bioavailable prodrug of GS-441524, the parental nucleoside of remdesivir, which targets the highly conserved RNA-dependent RNA polymerase. GS-621763 exhibited significant antiviral activity in lung cell lines and two different human primary lung cell culture systems. The dose-proportional pharmacokinetic profile observed after oral administration of GS-621763 translated to dose-dependent antiviral activity in mice infected with SARS-CoV-2. Therapeutic GS-621763 significantly reduced viral load, lung pathology, and improved pulmonary function in COVID-19 mouse model. A direct comparison of GS-621763 with molnupiravir, an oral nucleoside analog antiviral currently in human clinical trial, proved both drugs to be similarly efficacious. These data demonstrate that therapy with oral prodrugs of remdesivir can significantly improve outcomes in SARS-CoV-2 infected mice. Thus, GS-621763 supports the exploration of GS-441524 oral prodrugs for the treatment of COVID-19 in humans.

Efficacy and safety of current medications for treating severe and non-severe COVID-19 patients: an updated network meta-analysis of randomized placebo-controlled trials

BACKGROUND

Many recent studies have investigated the role of drug interventions for coronavirus disease 2019 (COVID-19) infection. However, an important question has been raised about how to select the effective and secure medications for COVID-19 patients. The aim of this analysis was to assess the efficacy and safety of the various medications available for severe and non-severe COVID-19 patients based on randomized placebo-controlled trials (RPCTs).

METHODS

We did an updated network meta-analysis. We searched the databases from inception until July 31, 2021, with no language restrictions. We included RPCTs comparing 49 medications and placebo in the treatment of severe and non-severe patients (aged 18 years or older) with COVID-19 infection. We extracted data on the trial and patient characteristics, and the following primary outcomes: all-cause mortality, the ratios of virological cure, and treatment-emergent adverse events. Odds ratio (OR) and their 95% confidence interval (CI) were used as effect estimates.

RESULTS

From 3,869 publications, we included 61 articles related to 73 RPCTs (57 in non-severe COVID-19 patients and 16 in severe COVID-19 patients), comprising 20,680 patients. The mean sample size was 160 (interquartile range 96-393) in this study. The median duration of follow-up drugs intervention was 28 days (interquartile range 21-30). For increase in virological cure, we only found that proxalutamide (OR 9.16, 95% CI 3.15-18.30), ivermectin (OR 6.33, 95% CI 1.22-32.86), and low dosage bamlanivimab (OR 5.29, 95% CI 1.12-24.99) seemed to be associated with non-severe COVID-19 patients when compared with placebo, in which proxalutamide seemed to be better than low dosage bamlanivimab (OR 5.69, 95% CI 2.43-17.65). For decrease in all-cause mortality, we found that proxalutamide (OR 0.13, 95% CI 0.09-0.19), imatinib (OR 0.49, 95% CI 0.25-0.96), and baricitinib (OR 0.58, 95% CI 0.42-0.82) seemed to be associated with non-severe COVID-19 patients; however, we only found that immunoglobulin gamma (OR 0.27, 95% CI 0.08-0.89) was related to severe COVID-19 patients when compared with placebo. For change in treatment-emergent adverse events, we only found that sotrovimab (OR 0.21, 95% CI 0.13-0.34) was associated with non-severe COVID-19 patients; however, we did not find any medications that presented a statistical difference when compared with placebo among severe COVID-19 patients.

CONCLUSION

We conclude that marked variations exist in the efficacy and safety of medications between severe and non-severe patients with COVID-19. It seems that monoclonal antibodies (e.g., low dosage bamlanivimab, baricitinib, imatinib, and sotrovimab) are a better choice for treating severe or non-severe COVID-19 patients. Clinical decisions to use preferentially medications should carefully consider the risk-benefit profile based on efficacy and safety of all active interventions in patients with COVID-19 at different levels of infection.

Clinical trial research on COVID-19 in Germany - a systematic analysis

Background: In 2020, the COVID-19 pandemic led to an unprecedented volume of almost 3,000 clinical trials registered worldwide. We aimed to describe the COVID-19 clinical trial research agenda in Germany during the first year of the pandemic. Methods: We identified randomized clinical trials assessing interventions to treat or prevent COVID-19 that were registered in 2020 and recruited or planned to recruit participants in Germany. We requested recruitment information from trial investigators as of April 2021. Results: In 2020, 65 trials were completely (n=27) or partially (n=38) conducted in Germany. Most trials investigated interventions to treat COVID-19 (86.2%; 56/65), in hospitalized patients (67.7%; 44/65), with industry funding (53.8%; 35/65). Few trials were completed (21.5%; 14/65). Overall, 187,179 participants were planned to be recruited (20,696 in Germany), with a median number of 106 German participants per trial (IQR 40 to 345). From the planned German participants, 13.4% were recruited (median 15 per trial (IQR 0 to 44). Conclusions: The overall German contribution to the worldwide COVID-19 clinical trial research agenda was modest. Few trials delivered urgently needed evidence. Most trials did not meet recruitment goals. Evaluation and international comparison of the challenges for conducting clinical trials in Germany is needed.

SARS-CoV-2-neutralising monoclonal antibodies for treatment of COVID-19

BACKGROUND

Monoclonal antibodies (mAbs) are laboratory-produced molecules derived from the B cells of an infected host. They are being investigated as a potential therapy for coronavirus disease 2019 (COVID-19).

OBJECTIVES

To assess the effectiveness and safety of SARS-CoV-2-neutralising mAbs for treating patients with COVID-19, compared to an active comparator, placebo, or no intervention. To maintain the currency of the evidence, we will use a living systematic review approach. A secondary objective is to track newly developed SARS-CoV-2-targeting mAbs from first tests in humans onwards.  SEARCH METHODS: We searched MEDLINE, Embase, the Cochrane COVID-19 Study Register, and three other databases on 17 June 2021. We also checked references, searched citations, and contacted study authors to identify additional studies. Between submission and publication, we conducted a shortened randomised controlled trial (RCT)-only search on 30 July 2021.

SELECTION CRITERIA

We included studies that evaluated SARS-CoV-2-neutralising mAbs, alone or combined, compared to an active comparator, placebo, or no intervention, to treat people with COVID-19. We excluded studies on prophylactic use of SARS-CoV-2-neutralising mAbs.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed search results, extracted data, and assessed risk of bias using the Cochrane risk of bias tool (RoB2). Prioritised outcomes were all-cause mortality by days 30 and 60, clinical progression, quality of life, admission to hospital, adverse events (AEs), and serious adverse events (SAEs). We rated the certainty of evidence using GRADE.

MAIN RESULTS

We identified six RCTs that provided results from 17,495 participants with planned completion dates between July 2021 and December 2031. Target sample sizes varied from 1020 to 10,000 participants. Average age was 42 to 53 years across four studies of non-hospitalised participants, and 61 years in two studies of hospitalised participants. Non-hospitalised individuals with COVID-19 Four studies evaluated single agents bamlanivimab (N = 465), sotrovimab (N = 868), regdanvimab (N = 307), and combinations of bamlanivimab/etesevimab (N = 1035), and casirivimab/imdevimab (N = 799). We did not identify data for mortality at 60 days or quality of life. Our certainty of the evidence is low for all outcomes due to too few events (very serious imprecision).  Bamlanivimab compared to placebo No deaths occurred in the study by day 29. There were nine people admitted to hospital by day 29 out of 156 in the placebo group compared with one out of 101 in the group treated with 0.7 g bamlanivimab (risk ratio (RR) 0.17, 95% confidence interval (CI) 0.02 to 1.33), 2 from 107 in the group treated with 2.8 g (RR 0.32, 95% CI 0.07 to 1.47) and 2 from 101 in the group treated with 7.0 g (RR 0.34, 95% CI 0.08 to 1.56). Treatment with 0.7 g, 2.8 g and 7.0 g bamlanivimab may have similar rates of AEs as placebo (RR 0.99, 95% CI 0.66 to 1.50; RR 0.90, 95% CI 0.59 to 1.38; RR 0.81, 95% CI 0.52 to 1.27). The effect on SAEs is uncertain. Clinical progression/improvement of symptoms or development of severe symptoms were not reported. Bamlanivimab/etesevimab compared to placebo There were 10 deaths in the placebo group and none in bamlanivimab/etesevimab group by day 30 (RR 0.05, 95% CI 0.00 to 0.81). Bamlanivimab/etesevimab may decrease hospital admission by day 29 (RR 0.30, 95% CI 0.16 to 0.59), may result in a slight increase in any grade AEs (RR 1.15, 95% CI 0.83 to 1.59) and may increase SAEs (RR 1.40, 95% CI 0.45 to 4.37). Clinical progression/improvement of symptoms or development of severe symptoms were not reported. Casirivimab/imdevimab compared to placebo Casirivimab/imdevimab may reduce hospital admissions or death (2.4 g: RR 0.43, 95% CI 0.08 to 2.19; 8.0 g: RR 0.21, 95% CI 0.02 to 1.79). We are uncertain of the effect on grades 3-4 AEs (2.4 g: RR 0.76, 95% CI 0.17 to 3.37; 8.0 g: RR 0.50, 95% CI 0.09 to 2.73) and SAEs (2.4 g: RR 0.68, 95% CI 0.19 to 2.37; 8.0 g: RR 0.34, 95% CI 0.07 to 1.65). Mortality by day 30 and clinical progression/improvement of symptoms or development of severe symptoms were not reported. Sotrovimab compared to placebo We are uncertain whether sotrovimab has an effect on mortality (RR 0.33, 95% CI 0.01 to 8.18) and invasive mechanical ventilation (IMV) requirement or death (RR 0.14, 95% CI 0.01 to 2.76). Treatment with sotrovimab may reduce the number of participants with oxygen requirement (RR 0.11, 95 % CI 0.02 to 0.45), hospital admission or death by day 30 (RR 0.14, 95% CI 0.04 to 0.48), grades 3-4 AEs (RR 0.26, 95% CI 0.12 to 0.60), SAEs (RR 0.27, 95% CI 0.12 to 0.63) and may have little or no effect on any grade AEs (RR 0.87, 95% CI 0.66 to 1.16).  Regdanvimab compared to placebo Treatment with either dose (40 or 80 mg/kg) compared with placebo may decrease hospital admissions or death (RR 0.45, 95% CI 0.14 to 1.42; RR 0.56, 95% CI 0.19 to 1.60, 206 participants), but may increase grades 3-4 AEs (RR 2.62, 95% CI 0.52 to 13.12; RR 2.00, 95% CI 0.37 to 10.70). 80 mg/kg may reduce any grade AEs (RR 0.79, 95% CI 0.52 to 1.22) but 40 mg/kg may have little to no effect (RR 0.96, 95% CI 0.64 to 1.43). There were too few events to allow meaningful judgment for the outcomes mortality by 30 days, IMV requirement, and SAEs.  Hospitalised individuals with COVID-19 Two studies evaluating bamlanivimab as a single agent (N = 314) and casirivimab/imdevimab as a combination therapy (N = 9785) were included.   Bamlanivimab compared to placebo  We are uncertain whether bamlanivimab has an effect on mortality by day 30 (RR 1.39, 95% CI 0.40 to 4.83) and SAEs by day 28 (RR 0.93, 95% CI 0.27 to 3.14). Bamlanivimab may have little to no effect on time to hospital discharge (HR 0.97, 95% CI 0.78 to 1.20) and mortality by day 90 (HR 1.09, 95% CI 0.49 to 2.43). The effect of bamlanivimab on the development of severe symptoms at day 5 (RR 1.17, 95% CI 0.75 to 1.85) is uncertain. Bamlanivimab may increase grades 3-4 AEs at day 28 (RR 1.27, 95% CI 0.81 to 1.98). We assessed the evidence as low certainty for all outcomes due to serious imprecision, and very low certainty for severe symptoms because of additional concerns about indirectness. Casirivimab/imdevimab with usual care compared to usual care alone Treatment with casirivimab/imdevimab compared to usual care probably has little or no effect on mortality by day 30 (RR 0.94, 95% CI 0.87 to 1.02), IMV requirement or death (RR 0.96, 95% CI 0.90 to 1.04), nor alive at hospital discharge by day 30 (RR 1.01, 95% CI 0.98 to 1.04). We assessed the evidence as moderate certainty due to study limitations (lack of blinding). AEs and SAEs were not reported.  AUTHORS' CONCLUSIONS: The evidence for each comparison is based on single studies. None of these measured quality of life. Our certainty in the evidence for all non-hospitalised individuals is low, and for hospitalised individuals is very low to moderate. We consider the current evidence insufficient to draw meaningful conclusions regarding treatment with SARS-CoV-2-neutralising mAbs. Further studies and long-term data from the existing studies are needed to confirm or refute these initial findings, and to understand how the emergence of SARS-CoV-2 variants may impact the effectiveness of SARS-CoV-2-neutralising mAbs. Publication of the 36 ongoing studies may resolve uncertainties about the effectiveness and safety of SARS-CoV-2-neutralising mAbs for the treatment of COVID-19 and possible subgroup differences.

Clinical Trials of COVID-19 Therapies Should Account for Diabetes and Hyperglycemia

Complications of Coronavirus Disease 2019 (COVID-19) occur with increased frequency in people admitted to the hospital with diabetes or hyperglycemia. The increased risk for COVID-19 infections in the presence of these metabolic conditions is in part due to overlapping pathophysiologic features of COVID-19, diabetes, and glucose control. Various antiviral treatments are being tested in COVID-19 patients. We believe that in these trials, it will be useful to evaluate treatment effect differences in patients stratified according to whether they have diabetes or hyperglycemia. In this way, it will be possible to better facilitate development of antiviral treatments that are most specifically beneficial for the large subset of COVID-19 patients who have diabetes or hyperglycemia.

Lectins enhance SARS-CoV-2 infection and influence neutralizing antibodies

SARS-CoV-2 infection-which involves both cell attachment and membrane fusion-relies on the angiotensin-converting enzyme 2 (ACE2) receptor, which is paradoxically found at low levels in the respiratory tract^1-3, suggesting that there may be additional mechanisms facilitating infection. Here we show that C-type lectin receptors, DC-SIGN, L-SIGN and the sialic acid-binding immunoglobulin-like lectin 1 (SIGLEC1) function as attachment receptors by enhancing ACE2-mediated infection and modulating the neutralizing activity of different classes of spike-specific antibodies. Antibodies to the amino-terminal domain or to the conserved site at the base of the receptor-binding domain, while poorly neutralizing infection of ACE2-overexpressing cells, effectively block lectin-facilitated infection. Conversely, antibodies to the receptor binding motif, while potently neutralizing infection of ACE2-overexpressing cells, poorly neutralize infection of cells expressing DC-SIGN or L-SIGN and trigger fusogenic rearrangement of the spike, promoting cell-to-cell fusion. Collectively, these findings identify a lectin-dependent pathway that enhances ACE2-dependent infection by SARS-CoV-2 and reveal distinct mechanisms of neutralization by different classes of spike-specific antibodies.

Safety, tolerability, pharmacokinetic characteristics, and immunogenicity of MW33: a Phase 1 clinical study of the SARS-CoV-2 RBD-targeting monoclonal antibody

MW33 is a fully humanized IgG1κ monoclonal neutralizing antibody, and may be used for the prevention and treatment of coronavirus disease 2019 (COVID-19). We conducted a randomized, double-blind, placebo-controlled, single-dose, dose-escalation Phase 1 study to evaluate the safety, tolerability, pharmacokinetics (PK), and immunogenicity of MW33. Healthy adults aged 18–45 years were sequentially enrolled into the 4, 10, 20, 40, and 60 mg/kg dose groups and infused with MW33 over 60 ± 15 min and followed for 85 days. All 42 enrolled participants completed the MW33 infusion, and 40 participants completed the 85-day follow-up period. 34 participants received a single infusion of 4 (n = 2), 10 (n = 8), 20 (n = 8), 40 (n = 8), and 60 mg/kg (n = 8) of MW33. 27 subjects in the test groups experienced 78 adverse events (AEs) post-dose, with an incidence of 79.4% (27/34). The most common AEs included abnormal laboratory test results, vascular and lymphatic disorders, and infectious diseases. The severity of AEs was mainly Grade 1 (92 AEs), and three Grade 2 and one Grade 4. The main PK parameters, maximum concentration (C_max), and area under the concentration-time curve (AUC_0–t, and AUC_0–∞) in 34 subjects showed a linear kinetic relationship in the range of 10–60 mg/kg. The plasma half-life was approximately 25 days. The positive rates of serum ADAs and antibody titres were low with no evidence of an impact on safety or PK. In conclusion, MW33 was well-tolerated, demonstrated linear PK, with a lower positive rate of serum ADAs and antibody titres in healthy subjects.

Trial registration:ClinicalTrials.gov identifier: NCT04427501.

Trial registration:ClinicalTrials.gov identifier: NCT04533048.

Trial registration:ClinicalTrials.gov identifier: NCT04627584.

First-in-Human Study of Bamlanivimab in a Randomized Trial of Hospitalized Patients With COVID-19

Therapeutics for patients hospitalized with coronavirus disease 2019 (COVID‐19) are urgently needed during the pandemic. Bamlanivimab is a potent neutralizing monoclonal antibody that blocks severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) attachment and entry into human cells, which could potentially lead to therapeutic benefit. J2W‐MC‐PYAA was a randomized, double‐blind, sponsor unblinded, placebo‐controlled, single ascending dose first‐in‐human trial (NCT04411628) in hospitalized patients with COVID‐19. A total of 24 patients received either placebo or a single dose of bamlanivimab (700 mg, 2,800 mg, or 7,000 mg). The primary objective was assessment of safety and tolerability, including adverse events and serious adverse events, with secondary objectives of pharmacokinetic (PK) and pharmacodynamic analyses. Treatment‐emergent adverse event (TEAE) rates were identical in the placebo and pooled bamlanivimab groups (66.7%). There were no apparent dose‐related increases in the number or severity of TEAEs. There were no serious adverse events or deaths during the study, and no discontinuations due to adverse events. PKs of bamlanivimab is linear and exposure increased proportionally with dose following single i.v. administration. The half‐life was ~ 17 days. These results demonstrate the favorable safety profile of bamlanivimab, and provided the initial critical evaluation of safety, tolerability, and PKs in support of the development of bamlanivimab in several ongoing clinical trials.

Therapeutic targets and interventional strategies in COVID-19: mechanisms and clinical studies

Owing to the limitations of the present efforts on drug discovery against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the lack of the understanding of the biological regulation mechanisms underlying COVID-19, alternative or novel therapeutic targets for COVID-19 treatment are still urgently required. SARS-CoV-2 infection and immunity dysfunction are the two main courses driving the pathogenesis of COVID-19. Both the virus and host factors are potential targets for antiviral therapy. Hence, in this study, the current therapeutic strategies of COVID-19 have been classified into "target virus" and "target host" categories. Repurposing drugs, emerging approaches, and promising potential targets are the implementations of the above two strategies. First, a comprehensive review of the highly acclaimed old drugs was performed according to evidence-based medicine to provide recommendations for clinicians. Additionally, their unavailability in the fight against COVID-19 was analyzed. Next, a profound analysis of the emerging approaches was conducted, particularly all licensed vaccines and monoclonal antibodies (mAbs) enrolled in clinical trials against primary SARS-CoV-2 and mutant strains. Furthermore, the pros and cons of the present licensed vaccines were compared from different perspectives. Finally, the most promising potential targets were reviewed, and the update of the progress of treatments has been summarized based on these reviews.